Greenhouse Gas Emissions and Fuel
Efficiency Standards for Medium- and
Heavy-Duty Engines and Vehicles -
Phase 2
Regulatory Impact Analysis
&EPA
United States
Environmental Protection
Agency
igNHTSA

-------

Greenhouse Gas Emissions and Fuel

Efficiency Standards for Medium- and

Heavy-Duty Engines and Vehicles -

Phase 2

Regulatory Impact Analysis

Office of Transportation and Air Quality
U.S. Environmental Protection Agency

And

National Highway Traffic Safety Administration
U.S. Department of Transportation
EPA-420-R-16-900

-------
TABLE OF CONTENTS
LIST OF ACRONYMS	ES-1
EXECUTIVE SUMMARY	ES-10
CHAPTER 1: INDUSTRY CHARACTERIZATION
1.1	Introduction	1-1
1.2	Trailers	1-1
1.3	Vocational Vehicles: Custom Chassis	1-8
CHAPTER 2: TECHNOLOGY AND COST
2.1	Overview of Technologies	2-1
2.2	Technology Principles - SI Engines	2-2
2.3	Technology Principles - CI Engines	2-9
2.4	Technology Principles - Class 4 to 8 Vehicles	2-19
2.5	Technology Application-HD Pickups and Vans	2-56
2.6	Technology Application-SI Engines	2-72
2.7	Technology Application and Estimated Costs - CI Engines	2-75
2.8	Technology Application and Estimated Costs - Tractors	2-94
2.9	Technology Application and Estimated Costs - Vocational Vehicles	2-148
2.10	Technology Application and Estimated Costs - Trailers	2-216
2.11	Technology Costs	2-265
2.12	Package Costs	2-350
CHAPTER 3: TEST PROCEDURES
3.1	Heavy-Duty Engine Test Procedure	3-1
3.2	Aerodynamic Assessment	3-5
3.3	Tire Rolling Resistance	3-47

-------
3.5	Tare Weights and Payload	3-71
3.6	Powertrain Test Procedures	3-74
3.7	Hybrid Powertrain Test Procedures	3-82
3.8	Axle Efficiency Test	3-85
3.9	Transmission Efficiency Test	3-86
3.10	HD Pickup Truck and Van Chassis Test Procedure	3-86
CHAPTER 4: VEHICLE SIMULATION MODEL
4.1	Purpose and Scope	4-1
4.2	Model Code Description	4-3
4.3	Validation of Phase 2 GEM Simulations	4-11
4.4	EPA and NHTSA HD Vehicle Compliance Model	4-27
4.5	Technology Improvements that Are Recognized in GEM without Simulation 4-42
CHAPTER 5: IMPACTS ON EMISSIONS AND FUEL CONSUMPTION
5.1	Executive Summary	5-1
5.2	Introduction	5-5
5.3	Program Analysis and Modeling Methods	5-6
5.4	Greenhouse Gas Emission and Fuel Consumption Impacts	5-26
5.5	Non-Greenhouse Gas Emission Impacts	5-42
CHAPTER 6: HEALTH AND ENVIRONMENTAL IMPACTS
6.1	Health and Environmental Effects of Non-GHG Pollutants	6-1
6.2	Impacts of the Rules on Concentrations of Non-GHG Pollutants	6-33
6.3	Changes in Atmospheric CO2 Concentrations, Global Mean Temperature,
Sea Level Rise, and Ocean pH Associated with the Program's GHG
Emissions Reductions	6-44

-------
CHAPTER 7: VEHICLE-RELATED COSTS, FUEL SAVINGS
7.1	Vehicle Costs, Fuel Savings and Maintenance Costs vs. the Dynamic Baseline
and Using Method A	7-1
7.2	Vehicle Costs, Fuel Savings and Maintenance Costs vs. the Flat Baseline
and using Method B	7-17
7.3	Key Parameters Used in the Estimation of Costs and Fuel Savings	7-48
CHAPTER 8: ECONOMIC AND OTHER IMPACTS
8.1	Framework for Benefits and Costs	8-1
8.2	Conceptual Framework for Evaluating Impacts	8-2
8.3	Analysis of the Rebound Effect	8-9
8.4	Impact on Class Shifting, Fleet Turnover, and Sales	8-22
8.5	Monetized GHG Impacts	8-26
8.6	Quantified and Monetized Non-GHG Health and Environmental Impacts 8-41
8.7	Additional Impacts	8-48
8.8	Petroleum, Energy and National Security Impacts	8-57
8.9	Summary of Benefits and Costs	8-71
8.10	Employment Impacts	8-78
8.11	Oil Price Sensitivity Analysis using Method B	8-90
APPENDIX 8.A TO CHAPTER 8 - SUPPLEMENTAL ANALYSIS OF
QUANTIFIED AND MONETIZED NON-GHG HEALTH AND
ENVIRONMENTAL IMPACTS	8-92
CHAPTER 9: SAFETY IMPACTS
9.1	Summary of Supporting HD Vehicle Safety Research	9-1
9.2	Safety Related Comments to the NPRM	9-9

-------
CHAPTER 10: CAFE MODEL FOR HD PICKUPS AND VANS
10.1	Overview of the CAFE Model	10-2
10.2	What Impacts Did NHTSA's "Method A" Analysis Show for Regulatory
Alternatives?	10-68
10.3	What Industry Impacts Did EPA's "Method B" Analysis Show for
Regulatory Alternatives?	10-119
CHAPTER 11: RESULTS OF THE PREFERRED AND ALTERNATIVE
11.1	What Are the Alternatives that the Agencies Considered?	11-1
11.2	How Do These Alternatives Compare in Overall GHG Emissions
Reductions and Fuel Efficiency?	11-19
CHAPTER 12: FINAL REGULATORY FLEXIBILITY ANALYSIS
12.1	Overview of the Regulatory Flexibility Act	12-1
12.2	Need for Rulemaking and Rulemaking Objectives	12-2
12.3	Definition and Description of Small Businesses	12-2
12.4	Summary of Small Entities to which the Rulemaking will Apply	12-3
12.5	Related Federal Rules	12-4
12.6	Projected Reporting, Recordkeeping, and Other Compliance Requirements 12-4
12.7	Regulatory Flexibilities	12-5
12.8	Projected Economic Effects of the Final Rulemaking	12-15
12.9	Summary of Economic Effects	12-19
CHAPTER 13: NATURAL GAS VEHICLES AND ENGINES
13.1	Detailed Lifecycle Analysis	13-1

-------

-------
Table of Contents, Acronym List, and Executive Summary
List of Acronyms
ng
Microgram
|im
Micrometers
2002$
U.S. Dollars in calendar year 2002
2009$
U.S. Dollars in calendar year 2009
A/C
Air Conditioning
ABS
Antilock Brake Systems
ABT
Averaging, Banking and Trading
AC
Alternating Current
ACES
Advanced Collaborative Emission Study
ALVW
Adjusted Loaded Vehicle Weight
AEO
Annual Energy Outlook
AES
Automatic Engine Shutdown
AHS
American Housing Survey
AMOC
Atlantic Meridional Overturning Circulation
AMT
Automated Manual Transmission
ANL
Argonne National Laboratory
APU
Auxiliary Power Unit
AQ
Air Quality
AQCD
Air Quality Criteria Document
AR4
Fourth Assessment Report
ARB
California Air Resources Board
ASL
Aggressive Shift Logic
ASPEN
Assessment System for Population Exposure Nationwide
AT
Automatic Transmissions
ATA
American Trucking Association
ATIS
Automated Tire Inflation System
ATRI
Alliance for Transportation Research Institute
AT SDR
Agency for Toxic Substances and Disease Registry
ATUS
American Time Use Survey
Avg
Average
BAC
Battery Air Conditioning
BenMAP
Benefits Mapping and Analysis Program
bhp
Brake Horsepower
bhp-hrs
Brake Horsepower Hours
BLS
Bureau of Labor Statistics
BSFC
Brake Specific Fuel Consumption
BTS
Bureau of Transportation Statistics
BTU
British Thermal Unit
CAA
Clean Air Act
CAAA
Clean Air Act Amendments

-------
CAD/CAE Computer Aided Design And Engineering
CAE	Computer Aided Engineering
CAFE	Corporate Average Fuel Economy
CARB	California Air Resources Board
CBI	Confidential Business Information
CCP	Coupled Cam Phasing
CCSP	Climate Change Science Program
Cd	Coefficient of Drag
CdA	Drag Area
CDC	Centers for Disease Control
CFD	Computational Fluid Dynamics
CFR	Code of Federal Regulations
CH4	Methane
CILCC	Combined International Local and Commuter Cycle
CITT	Chemical Industry Institute of Toxicology
CMAQ	Community Multiscale Air Quality
CO	Carbon Monoxide
CO2	Carbon Dioxide
CCheq	CO2 Equivalent
COFC	Container-on-Flatcar
COI	Cost of Illness
COPD	Chronic Obstructive Pulmonary Disease
CoV	Coefficient of Variation
CPS	Cam Profile Switching
CRC	Coordinating Research Council
CRGNSA	Columbia River Gorge National Scenic Area
CRR	Rolling Resistance Coefficient
CS	Climate Sensitivity
CSI	Cambridge Systematics Inc.
CSS	Coastal Sage Scrub
CSV	Comma-separated Values
CVD	Cardiovascular Disease
CVT	Continuously-Variable Transmission
CW	Curb Weight
D/UAF	Downward and Upward Adjustment Factor
DCP	Dual Cam Phasing
DCT	Dual Clutch Transmission
DE	Diesel Exhaust
DEAC	Cylinder Deactivation
DEER	Diesel Engine-Efficiency and Emissions Research
DEF	Diesel Exhaust Fluid
DHHS	U.S. Department of Health and Human Services
Diesel HAD Diesel Health Assessment Document

-------
DMC
DO
DOC
DOD
DOE
DOHC
DOT
DPF
DPM
DR
DRIA
DVVL
EC
EC
ECU
ED
EERA
EFR
EGR
EHPS
EIA
EISA
EMS-HAP
EO
EPA
EPS
ERG
ESC
EV
F
FEL
FET
FEV1
FHWA
FIA
FMCSA
FOH
FR
FTP
FVC
g
g/s
Direct Manufacturing Costs
Dissolved Oxygen
Diesel Oxidation Catalyst
Department of Defense
Department of Energy
Dual Overhead Camshaft Engines
Department of Transportation
Diesel Particulate Filter
Diesel Particulate Matter
Discount Rate
Draft Regulatory Impact Analysis
Discrete Variable Valve Lift
European Commission
Elemental Carbon
Electronic Control Unit
Emergency Department
Energy and Environmental Research Associates
Engine Friction Reduction
Exhaust Gas Recirculation
Electrohydraulic Power Steering
Energy Information Administration (part of the U.S. Department of
Energy)
Energy Independence and Security Act
Emissions Modeling System for Hazardous Air Pollution
Executive Order
Environmental Protection Agency
Electric Power Steering
Eastern Research Group
Electronic Stability Control
Electric Vehicle
Frequency
Family Emission Limit
Federal Excise Tax
Functional Expiratory Volume
Federal Highway Administration
Forest Inventory and Analysis
Federal Motor Carrier Safety Administration
Fuel Operated Heater
Federal Register
Federal Test Procedure
Forced Vital Capacity
Gram
Gram-per-second

-------
g/ton-mile	Grams emitted to move one ton (2000 pounds) of freight over one mile
gal	Gallon
gal/1000 ton- Gallons of fuel used to move one ton of payload (2,000 pounds) over
mile	1000 miles
GCAM	Global Change Assessment Model
GCW	Gross Combined Weight
GDP	Gross Domestic Product
GEM	Greenhouse gas Emissions Model
GEOS	Goddard Earth Observing System
GHG	Greenhouse Gases
GIFT	Geospatial Intermodal Freight Transportation
Greenhouse Gases, Regulated Emissions, and Energy Use in
GREET	Transportation
GSF1	Generic Speed Form one
GUI	Graphical User Interface
GVWR	Gross Vehicle Weight Rating
GWP	Global Warming Potential
HABs	Harmful Algal Blooms
HAD	Diesel Health Assessment Document
HC	Hydrocarbon
HD	Heavy-Duty
HDUDDS	Heavy Duty Urban Dynamometer Driving Cycle
HEG	High Efficiency Gearbox
HEI	Health Effects Institute
HES	Health Effects Subcommittee
HEV	Hybrid Electric Vehicle
HFC	Hydrofluorocarbon
HFET	Highway Fuel Economy Dynamometer Procedure
HHD	Heavy Heavy-Duty
HHDDT	Highway Heavy-Duty Diesel Transient
hp	Horsepower
hrs	Hours
HRV	Heart Rate Variability
HSC	High Speed Cruise Duty Cycle
HTUF	Hybrid Truck User Forum
hz	Hertz
IARC	International Agency for Research on Cancer
IATC	Improved Automatic Transmission Control
IC	Indirect Costs
ICCT	International Council on Clean Transport
ICD	International Classification of Diseases
ICF	ICF International
ICM	Indirect Cost Multiplier

-------
ICP
Intake Cam Phasing
IMAC
Improved Mobile Air Conditioning
IMPROVE
Interagency Monitoring of Protected Visual Environments
IPCC
Intergovernmental Panel on Climate Change
IRFA
Initial Regulatory Flexibility Analysis
IRIS
Integrated Risk Information System
ISA
Integrated Science Assessment
JAMA
Journal of the American Medical Association
k
Thousand
kg
Kilogram
KI
kinetic intensity
km
Kilometer
km/h
Kilometers per Hour
kW
Kilowatt
L
Liter
lb
Pound
LD
Light-Duty
LHD
Light Heavy-Duty
LLNL
Lawrence Livermore National Laboratory's
LRR
Lower Rolling Resistance
LSC
Low Speed Cruise Duty Cycle
LT
Light Trucks
LTCCS
Large Truck Crash Causation Study
LUB
Low Friction Lubes
LUC
Land Use Change
m2
Square Meters
m3
Cubic Meters
MAGIC C
Model for the Assessment of Greenhouse-gas Induced Climate Change
MCF
Mixed Conifer Forest
MD
Medium-Duty
MDPV
Medium-Duty Passenger Vehicles
mg
Milligram
MHD
Medium Heavy-Duty
MHEV
Mild Hybrid
mi
mile
min
Minute
MM
Million
MMBD
Million Barrels per Day
MMT
Million Metric Tons
MOVES
Motor Vehicle Emissions Simulator
mpg
Miles per Gallon
mph
Miles per Hour
MSAT
Mobile Source Air Toxic

-------
MRL
Minimal Risk Level
MT
Manual Transmission
MY
Model Year
N20
Nitrous Oxide
NA
Not Applicable
NAAQS
National Ambient Air Quality Standards
NAFA
National Association of Fleet Administrators
NAICS
North American Industry Classification System
NAS
National Academy of Sciences
NATA
National Air Toxic Assessment
NCAR
National Center for Atmospheric Research
NCI
National Cancer Institute
NCLAN
National Crop Loss Assessment Network
NEC
Net Energy Change Tolerance
NEI
National Emissions Inventory
NEMS
National Energy Modeling System
NEPA
National Environmental Policy Act
NESCAUM
Northeastern States for Coordinated Air Use Management
NESCCAF
Northeast States Center for a Clean Air Future
NESHAP
National Emissions Standards for Hazardous Air Pollutants
NHS
National Highway System
NHTSA
National Highway Traffic Safety Administration
NiMH
Nickel Metal-Hydride
NIOSH
National Institute of Occupational Safety and Health
Nm
Newton-meters
NMHC
Nonmethane Hydrocarbons
NMMAPS
National Morbidity, Mortality, and Air Pollution Study
NOx
Nitrogen Oxide
N02
Nitrogen Dioxide
NO A A
National Oceanic and Atmospheric Administration
NOx
Oxides of Nitrogen
NPRM
Notice of Proposed Rulemaking
NPV
Net Present Value
NRC
National Research Council
NRC-CAN
National Research Council of Canada
NREL
National Renewable Energy Laboratory
NTP
National Toxicology Program
NVH
Noise Vibration and Harshness
O&M
Operating and maintenance
03
Ozone
OAQPS
Office of Air Quality Planning and Standards
OC
Organic Carbon
OE
Original Equipment

-------
OEHHA	Office of Environmental Health Hazard Assessment
OEM	Original Equipment Manufacturer
OHV	Overhead Valve
OMB	Office of Management and Budget
OPEC	Organization of Petroleum Exporting Countries
ORD	EPA's Office of Research and Development
ORNL	Oak Ridge National Laboratory
OTAQ	Office of Transportation and Air Quality
Pa	Pascal
PAH	Polycyclic Aromatic Hydrocarbons
PEF	Peak Expiratory Flow
PEMS	Portable Emissions Monitoring System
PGM	Platinum Group Metal
PHEV	Plug-in Hybrid Electric Vehicles
PM	Particulate Matter
PM 10	Coarse Particulate IVIatter (diameter of 10 lim or less)
PM2.5	Fine Particulate Matter (diameter of 2.5 |im or less)
POM	Polycyclic Organic Matter
Ppb	Parts per Billion
Ppm	Parts per Million
Psi	Pounds per Square Inch
PTO	Power Take Off
R&D	Research and Development
RBM	Resisting Bending Moment
REL	Reference Exposure Level
RESS	Rechargeable Energy Storage System
RFA	Regulatory Flexibility Act
RfC	Reference Concentration
RFS2	Renewable Fuel Standard 2
RIA	Regulatory Impact Analysis
RPE	Retail Price Equivalent
Rpm	Revolutions per Minute
RSWT	Reduced-Scale Wind Tunnel
S	Second
SAB	Science Advisory Board
SAB-HES	Science Advisory Board - Health Effects Subcommittee
SAE	Society of Automotive Engineers
SAR	Second Assessment Report
SAV	Submerged Aquatic Vegetation
SBA	Small Business Administration
SBAR	Small Business Advocacy Review
SBREFA	Small Business Regulatory Enforcement Fairness Act
SCC	Social Cost of Carbon

-------
SCR
Selective Catalyst Reduction
SER
Small Entity Representation
SET
Supplemental Emission Test
SGDI
Stoichiometric Gasoline Direct Injection
SHEV
Strong Hybrid Vehicles
SI
Spark-Ignition
SIDI
Spark Ignition Direct Injection
S02
Sulfur Dioxide
SOx
Sulfur Oxides
SOA
Secondary Organic Aerosol
SOC
State of Charge
SOHC
Single Overhead Cam
SOx
Oxides of Sulfur
SPR
Strategic Petroleum Reserve
STB
Surface Transportation Board
Std.
Standard
STP
Scaled Tractive Power
SUV
Sport Utility Vehicle
SVOC
Semi-Volatile Organic Compound
SwRI
Southwest Research Institute
TAR
Technical Assessment Report
TC
Total Costs
TCp
Total Cost package
TDS
Turbocharging And Downsizing
THC
Total Hydrocarbon
TIAX
TIAX LLC
TMC
Technology & Maintenance Council
TOFC
Trailer-on-Flatcar
Ton-mile
One ton (2000 pounds) of payload over one mile
TPM
Tire Pressure Monitoring
TRBDS
Turbocharging and Downsizing
TRU
Trailer Refrigeration Unit
TSD
Technical Support Document
TSS
Thermal Storage
TTMA
Truck Trailer Manufacturers Association
TW
Test Weight
U/DAF
Upward and Downward Adjustment Factor
UCT
Urban Creep and Transient Duty Cycle
UFP
Ultra Fine Particles
LIRE
Unit Risk Estimate
USD A
United States Department of Agriculture
USGCRP
United States Global Change Research Program
UV
Ultraviolet

-------
UV-b
Ultraviolet-b
VHHD
Vocational Heavy Heavy-Duty
VIN
Vehicle Identification Number
VIUS
Vehicle Inventory Use Survey
VLHD
Vocational Light Heavy-Duty
VMHD
Vocational Medium Heavy-Duty
VMT
Vehicle Miles Traveled
VOC
Volatile Organic Compound
VSL
Vehicle Speed Limiter
VTRIS
Vehicle Travel Information System
VVL
Variable Valve Lift
VVT
Variable Valve Timing
WACAP
Western Airborne Contaminants Assessment Project
WBS
Wide Base Singles
WHR
Waste Heat Recovery
WHTC
World Harmonized Transient Cycle
WHVC
World Harmonized Vehicle Cycle
WRF
Weather Research Forecasting
WTP
Willingness-to-Pay
WTVC
World Wide Transient Vehicle Cycle
WVU
West Virginia University

-------
Executive Summary
The Environmental Protection Agency (EPA) and the National Highway Traffic Safety
Administration (NHTSA), on behalf of the Department of Transportation, are each finalizing
changes to our comprehensive Heavy-Duty National Program. The Program will further reduce
greenhouse gas emissions (GHG) and increase fuel efficiency for on-road heavy-duty vehicles,
responding to the President's directive on February 18, 2014, to take coordinated steps toward
the production of even cleaner vehicles. NHTSA's fuel consumption standards and EPA's
carbon dioxide (CO2) emissions standards are tailored to each of the three current regulatory
categories of heavy-duty vehicles: (1) Combination Tractors; (2) Heavy-duty Pickup Trucks and
Vans; and (3) Vocational Vehicles, as well as gasoline and diesel heavy-duty engines. In
addition, the agencies are adding new standards for combination trailers. EPA's
hydrofluorocarbon emissions standards that currently apply to air conditioning systems in
tractors, pickup trucks, and vans, will also be applied to vocational vehicles.
Table 1 presents the rule-related technology costs, maintenance costs, fuel savings, other
benefits, and net benefits in both present-value and annualized terms for Method A. This table
shows the costs and benefits relative to the dynamic baseline. Table 2 presents the rule-related
fuel savings, costs, benefits and net benefits in both present value terms and in annualized terms
as calculated for Method B relative to the flat baseline.

-------
Table 1 NHTSA's Estimated 2018-2029 Model Year Lifetime Discounted Costs,
Benefits, and Net Benefits using Method A, Relative to the Dynamic Baselinea, and
Assuming the 3% Discount Rate SC-GHG Values
(Billions of 2013 Dollars)
Lifetime Present Value - 3% Discount Rate
Vehicle Program
-$23.7
Maintenance
-$1.7
Fuel Savings
$149.1
Benefits (less costs by increased vehicle use)
$72.8
Net Benefitsb
$196.5
Annualized Value - 3% Discount Rate
Vehicle Program
-$0.9
Maintenance
-$0.1
Fuel Savings
$5.9
Benefits (less costs by increased vehicle use)
$2.9
Net Benefitsb
$7.8
Lifetime Present Value - 7% Discount Rate
Vehicle Program
-$16.1
Maintenance
-$0.9
Fuel Savings
$79.7
Benefits (less costs by increased vehicle use)
$54.6
Net Benefitsb
$117.3
Annualized Value - 7% Discount Rate
Vehicle Program
-$1.2
Maintenance
-$0.1
Fuel Savings
$5.8
Benefits (less costs by increased vehicle use)
$4.0
Net Benefitsb
$8.5
Notes:
a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for
an explanation of the flat baseline, la, and dynamic baseline, lb, please see Preamble
Section X.A.I
b Net benefits reflect the fuel savings plus benefits minus costs.

-------
Table 2 EPA's Estimated 2018-2029 Model Year Lifetime Discounted Costs, Benefits, and Net
Benefits using Method B and Relative to the Flat Baseline and Assuming the 3% Discount Rate SC-GHG
Values" (Billions of 2013 Dollars)
Lifetime Present Valuec - 3% Discount Rate
Vehicle Program
-$27
Maintenance
-$1.9
Fuel Savings
$169
Benefitsb
$88
Net Benefits'1
$229
Annualized Va
uee - 3% Discount Rate
Vehicle Program
-$1.4
Maintenance
-$0.1
Fuel Savings
$8.6
Benefitsb
$4.5
Net Benefits'1
$11.7
Lifetime Present Valuec - 7% Discount Rate
Vehicle Program
-$18
Maintenance
-$0.9
Fuel Savings
$87
Benefitsb
$62
Net Benefits'1
$131
Annualized Va
uee - 7% Discount Rate
Vehicle Program
-$1.4
Maintenance
-$0.1
Fuel Savings
$7.0
Benefitsb
$3.9
Net Benefits'1
$9.4
Notes:
a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an
explanation of the flat baseline, la, and dynamic baseline, lb, please see Preamble Section X. A. 1
b EPA estimated the benefits associated with reductions in GHGs (CO2, CH4, and N20) using four
different values of a one ton reduction in each gas. The four values applied to each GHG are: model
average at 2.5% discount rate, 3%, and 5%; 95th percentile at 3% and each increases over time. For
the purposes of this overview presentation of estimated costs and benefits, however, the benefits
shown here use the central marginal value: the model average at 3% discount rate, in 2013 dollars.
Chapter 8.5 provides a complete list of values for the 4 estimates for each GHG. Note that net
present value of reduced GHG emissions is calculated differently than other benefits. The same
discount rate used to discount the value of damages from future emissions (marginal values, i.e.
SC-GHGs, at 5, 3, and 2.5 percent) is used to calculate net present value of GHG benefits for
internal consistency. Refer to Section Chapter 8.5 for more detail.
0 Present value is the total, aggregated amount that a series of monetized costs or benefits that occur
over time is worth now (in year 2013 dollar terms), discounting future values, over the lifetime of
each model year vehicle, to calendar year 2015.
d Net benefits reflect the fuel savings plus benefits minus costs.
e The annualized value is the constant annual value through a 30 year lifetime whose summed
present value equals the present value from which it was derived. Annualized SC-GHG values are
calculated using the same rate as that used to determine the SC-GHG value, while all other costs
and benefits are annualized at either 3% or 7%.

-------
Table 3 Summary of Final 2021 Standards Including Average Per Vehicle Costs and Projected Improvement
REGULATORY
SUBCATEGORY
CO2 GRAMS
PER TON-
MILE
FUEL
CONSUMPTION
GALLON PER 1,000
TON-MILE
AVERAGE
INCREMENTAL
COST PER
VEHICLE
RELATIVE TO
PHASE 1 COSTS IN
MODEL YEAR
2021 A
AVERAGE
PERCENT FUEL
CONSUMPTION
AND CO2
IMPROVEMENT IN
MY 2021 RELATIVE
TO MY 2017
Tractors
Class 7 Low Roof Day Cab
105.5
10.36346
$5,134
11%
Class 7 Mid Roof Day Cab
113.2
11.11984
$5,134
11%
Class 7 High Roof Day Cab
113.5
11.14931
$5,240
12%
Class 8 Low Roof Day Cab
80.5
7.90766
$5,228
12%
Class 8 Mid Roof Day Cab
85.4
8.38900
$5,228
12%
Class 8 High Roof Day Cab
85.6
8.40864
$5,317
13%
Class 8 Low Roof Sleeper Cab
72.3
7.10216
$7,181
14%
Class 8 Mid Roof Sleeper Cab
78.0
7.66208
$7,175
14%
Class 8 High Roof Sleeper Cab
75.7
7.43615
$7,276
14%
Class 8
Heavy-Haul
52.4
5.14735
$5,063
8%
Trailers
Long Dry Box Trailer
78.9
7.75049
$1,081
5%
Short Dry Box Trailer
123.7
12.15128
$772
2%
Long Refrigerated Box Trailer
80.6
7.91749
$1,081
5%
Short Refrigerated Box Trailer
127.5
12.52456
$772
2%
Vocational Diesel
LHD Urban
424
41.6503
$1,106
12%
LHD Multi-Purpose
373
36.6405
$1,164
11%
LHD Regional
311
30.5501
$873
7%
MHD Urban
296
29.0766
$1,116
11%
MHD Multi-Purpose
265
26.0314
$1,146
10%
MHD Regional
234
22.9862
$851
6%
HELD Urban
308
30.2554
$1,334
9%
HELD Multi-Purpose
261
25.6385
$1,625
9%
HELD Regional
205
20.1375
$2,562
7%
Vocational Gasoline
LHD Urban
461
51.8735
$1,106
8%
LHD Multi-Purpose
407
45.7972
$1,164
8%
LHD Regional
335
37.6955
$873
6%
MHD Urban
328
36.9078
$1,116
7%
MHD Multi-Purpose
293
32.9695
$1,146
7%
MHD Regional
261
29.3687
$851
5%
Note:
a Engine costs are included in average vehicle costs. These costs are based on our projected market adoption rates
of various technologies and these costs include indirect costs via markups along with learning impacts. For a
description of the markups and learning impacts considered in this analysis and how it impacts technology costs for
other years, refer to Chapter 2 of the RIA (see RIA 2.11).

-------
Table 4 Summary of Final 2024 Standards Including Average Per Vehicle Costs and Projected Improvement
REGULATORY
SUBCATEGORY
CO2
GRAMS
PER TON-
MILE
FUEL
CONSUMPTION
GALLON PER
1,000 TON-MILE
AVERAGE
INCREMENTAL
COST PER VEHICLE
RELATIVE TO
PHASE 1 COSTS IN
MODEL YEAR 2024 A
AVERAGE PERCENT
FUEL CONSUMPTION
AND CO2
IMPROVEMENT IN
MY 2024 RELATIVE
TO MY 2017
Tractors
Class 7 Low Roof Day Cab
99.8
9.80354
$8,037
16%
Class 7 Mid Roof Day Cab
107.1
10.52063
$8,037
16%
Class 7 High Roof Day Cab
106.6
10.47151
$8,210
18%
Class 8 Low Roof Day Cab
76.2
7.48527
$8,201
17%
Class 8 Mid Roof Day Cab
80.9
7.94695
$8,201
16%
Class 8 High Roof Day Cab
80.4
7.89784
$8,358
18%
Class 8 Low Roof Sleeper Cab
68.0
6.67976
$11,100
19%
Class 8 Mid Roof Sleeper Cab
73.5
7.22004
$11,100
19%
Class 8 High Roof Sleeper Cab
70.7
6.94499
$11,306
19%
Class 8
Heavy-Haul
50.2
4.93124
$7,937
12%
Trailers
Long Dry Box Trailer
77.2
7.58350
$1,204
7%
Short Dry Box Trailer
120.9
11.87623
$1,171
4%
Long Refrigerated Box Trailer
78.9
7.75049
$1,204
7%
Short Refrigerated Box Trailer
124.7
12.24951
$1,171
4%
Vocational Diesel
LHD Urban
385
37.8193
$1,959
20%
LHD Multi-Purpose
344
33.7917
$2,018
18%
LHD Regional
296
29.0766
$1,272
11%
MHD Urban
271
26.6208
$2,082
18%
MHD Multi-Purpose
246
24.1650
$2,110
16%
MHD Regional
221
21.7092
$1,274
11%
HELD Urban
283
27.7996
$2,932
16%
HELD Multi-Purpose
242
23.7721
$3,813
16%
HELD Regional
194
19.0570
$4,009
12%
Vocational Gasoline
LHD Urban
432
48.6103
$1,959
13%
LHD Multi-Purpose
385
43.3217
$2,018
9%
LHD Regional
324
36.4577
$1,272
12%
MHD Urban
310
34.8824
$2,082
11%
MHD Multi-Purpose
279
31.3942
$2,110
9%
MHD Regional
251
28.2435
$1,274
13%
Note:
a Engine costs are included in average vehicle costs. These costs are based on our projected market adoption rates
of various technologies and these costs include indirect costs via markups along with learning impacts. For a
description of the markups and learning impacts considered in this analysis and how it impacts technology costs for
other years, refer to Chapter 2 of the RIA (see RIA 2.11).

-------
Table 5 Summary of Final 2027 Standards Including Average Per Vehicle Costs and Projected Improvement
REGULATORY
CO2 GRAMS
FUEL
AVERAGE
AVERAGE PERCENT
SUBCATEGORY
PER TON-
CONSUMPTION
INCREMENTAL COST
FUEL

MILE (FOR
GALLON PER 1,000
PER VEHICLE
CONSUMPTION

HDPUV,
TON-MILE (FOR
RELATIVE TO PHASE
AND CO2

GRAMS PER
HDPUV,
1 COSTS IN MODEL
IMPROVEMENT IN

MILE)
GALLONS PER 100
MILES)
YEAR 2027 A
MY 2027 RELATIVE
TO MY 2017
Tractors
Class 7 Low Roof Day Cab
96.2
9.44990
$10,235
19%
Class 7 Mid Roof Day Cab
103.4
10.15717
$10,235
19%
Class 7 High Roof Day Cab
100.0
9.82318
$10,298
21%
Class 8 Low Roof Day Cab
73.4
7.21022
$10,439
20%
Class 8 Mid Roof Day Cab
78.0
7.66208
$10,439
19%
Class 8 High Roof Day Cab
75.7
7.43615
$10,483
22%
Class 8 Low Roof Sleeper Cab
64.1
6.29666
$13,535
24%
Class 8 Mid Roof Sleeper Cab
69.6
6.83694
$13,574
23%
Class 8 High Roof Sleeper Cab
64.3
6.31631
$13,749
25%
Class 8
Heavy-Haul
48.3
4.74460
$9,986
15%
Trailers
Long Dry Box Trailer
75.7
7.43615
$1,370
9%
Short Dry Box Trailer
119.4
11.72888
$1,204
6%
Long Refrigerated Box Trailer
77.4
7.60314
$1,370
9%
Short Refrigerated Box Trailer
123.2
12.10216
$1,204
5%
Vocational Diesel
LHD Urban
367
36.0511
$2,533
24%
LHD Multi-Purpose
330
32.4165
$2,571
21%
LHD Regional
291
28.5855
$1,486
13%
MHD Urban
258
25.3438
$2,727
22%
MHD Multi-Purpose
235
23.0845
$2,771
20%
MHD Regional
218
21.4145
$1,500
12%
HHD Urban
269
26.4244
$4,151
20%
HHD Multi-Purpose
230
22.5933
$5,025
20%
HHD Regional
189
18.5658
$5,670
14%
Vocational Gasoline
LHD Urban
413
46.4724
$2,533
18%
LHD Multi-Purpose
372
41.8589
$2,571
16%
LHD Regional
319
35.8951
$1,486
11%
MHD Urban
297
33.4196
$2,727
16%
MHD Multi-Purpose
268
30.1564
$2,771
15%
MHD Regional
247
27.7934
$1,500
10%
Class 2b and 3 HD Pickups and Vansb
HD Pickup and Van
460
4.88
$1,486
17%
Notes:
" Engine costs are included in average vehicle costs. These costs are based on our projected market adoption rates
of various technologies and these costs include indirect costs via markups along with learning impacts. For a
description of the markups and learning impacts considered in this analysis and how it impacts technology costs for
other years, refer to Chapter 2 of the RIA (see RIA 2.11).
b For HD pickups and vans, Table 5 shows results for MY2029, assuming continuation of MY2027 standard.

-------
Table 6 Summary of Final 2021 and 2024 Custom Chassis Vocational Standards Including Average Per
Vehicle Costs and Projected Improvement
REGULATORY
SUBCATEGORY
CO2 GRAMS PER
TON-MILE
FUEL
CONSUMPTION
GALLON PER 1,000
TON-MILE
AVERAGE
INCREMENTAL
COST PER
VEHICLE
RELATIVE TO
PHASE 1 COSTS IN
MODEL YEAR
2021 A
AVERAGE
PERCENT FUEL
CONSUMPTION
AND CO2
IMPROVEMENT IN
MY 2021 RELATIVE
TO MY 2017
Vocational Custom Chassis
Coach Bus
210
20.6287
900
7%
Motor Home
228
22.3969
600
6%
School Bus
291
28.5855
800
10%
Transit
300
29.4695
1000
7%
Refuse
313
30.7466
700
4%
Mixer
319
31.3360
300
3%
Emergency
324
31.8271
400
1%
Note:
a Engine costs are included in average vehicle costs. These costs are based on our projected market adoption rates
of various technologies and these costs include indirect costs via markups along with learning impacts. For a
description of the markups and learning impacts considered in this analysis and how it impacts technology costs for
other years, refer to Chapter 2 of the RIA (see RIA 2.11).
Table 7 Summary of Final 2027 Custom Chassis Vocational Standards Including Average Per Vehicle Costs
and Projected Improvement
REGULATORY
SUBCATEGORY
CO2 GRAMS PER
TON-MILE
FUEL
CONSUMPTION
GALLON PER 1,000
TON-MILE
AVERAGE
INCREMENTAL
COST PER
VEHICLE
RELATIVE TO
PHASE 1 COSTS IN
MODEL YEAR
2027 A
AVERAGE
PERCENT FUEL
CONSUMPTION
AND CO2
IMPROVEMENT IN
MY 2027 RELATIVE
TO MY 2017
Vocational Custom Chassis
Coach Bus
205
20.1375
1400
11%
Motor Home
226
22.2004
900
9%
School Bus
271
26.6208
1300
18%
Transit
286
28.0943
1800
14%
Refuse
298
29.2731
1300
12%
Mixer
316
31.0413
600
7%
Emergency
319
31.3360
600
6%
Note:
a Engine costs are included in average vehicle costs. These costs are based on our projected market adoption rates
of various technologies and these costs include indirect costs via markups along with learning impacts. For a
description of the markups and learning impacts considered in this analysis and how it impacts technology costs for
other years, refer to Chapter 2 of the RIA (see RIA 2.11).

-------
This Regulatory Impact Analysis (RIA) provides detailed supporting documentation to
EPA and NHTSA joint rules under each of their respective statutory authorities. Because there
are slightly different requirements and flexibilities in the two authorizing statutes, this RIA
provides documentation for the primary joint provisions as well as for provisions specific to each
agency.
This RIA is generally organized to provide overall background information,
methodologies, and data inputs, followed by results of the various technical and economic
analyses. A summary of each chapter of the RIA follows.
Chapter 1: Industry Characterization. In order to assess the impacts of greenhouse gas
(GHG) and fuel consumption regulations upon the affected industries, it is important to
understand the nature of the industries impacted by the regulations. This chapter provides
market information for the trailer industry, as well as the variety of ownership patterns, for
background purposes. It also provides information on the vocational vehicle industry.
Chapter 2: Technology and Cost. This chapter presents details of the vehicle and
engine technologies and technology packages for reducing greenhouse gas emissions and fuel
consumption. These technologies and technology packages represent potential ways that the
industry could meet the CO2 and fuel consumption stringency levels, and they provide the basis
for the technology costs and effectiveness analyses.
Chapter 3: Test Procedures. Laboratory procedures to physically test engines, vehicles,
and components are a crucial aspect of the heavy-duty vehicle GHG and fuel consumption
program. The rulemaking will establish some new test procedures for both engine and vehicle
compliance and will revise existing procedures. This chapter describes the relevant test
procedures, including methodologies for assessing engine emission performance, the effects of
aerodynamics and tire rolling resistance, as well as procedures for chassis dynamometer testing
and their associated drive cycles.
Chapter 4: Vehicle Simulation Model. An important aspect of a regulatory program is
its ability to accurately estimate the potential environmental benefits of heavy-duty truck
technologies through testing and analysis. Most large truck manufacturers employ various
computer simulation methods to estimate truck efficiency for purposes of developing and
refining their products. Each method has advantages and disadvantages. This section will focus
on the use of a type truck simulation modeling that the agencies have developed specifically for
assessing tailpipe GHG emissions and fuel consumption for purposes of this rulemaking. The
agencies will revise the existing simulation model — the "Greenhouse gas Emissions Model
(GEM)" — as the primary tool to certify vocational vehicles, combination tractor, and
combination trailers, Class 2b through Class 8 heavy-duty vehicles that are not heavy-duty
pickups or vans) and discuss the model in this chapter.
Chapter 5: Impacts on Emissions and Fuel Consumption. This program estimates
anticipated impacts from the CO2 emission and fuel efficiency standards. The agencies quantify
fuel use and emissions from the GHGs carbon dioxide (CO2), methane (CH4), nitrous oxide
(N2O) and hydrofluorocarbons (HFCs). In addition to reducing the emissions of greenhouse
gases and fuel consumption, this program will also influence the emissions of "criteria" air

-------
pollutants, including carbon monoxide (CO), fine particulate matter (PM2.5) and sulfur dioxide
(SOx) and the ozone precursors hydrocarbons (VOC) and oxides of nitrogen (NOx); and several
air toxics (including benzene, 1,3-butadiene, formaldehyde, acetaldehyde, and acrolein), as
described further in Chapter 5.
The agencies used EPA's Motor Vehicle Emission Simulator (MOVES2014a) to estimate
downstream (tailpipe) emission impacts for combination tractors and vocational vehicles, and a
spreadsheet model based on emission factors the "GREET" model to estimate upstream (fuel
production and distribution) emission changes resulting from the decreased fuel. For HD
pickups and vans, the agencies used DOT's CAFE model to estimate manufacturer responses to
these standards. NHTSA used the CAFE model to estimate emission impacts, and EPA used the
MOVES model to calculate emission impacts using CAFE model technology penetration outputs
as an input. Based on these analyses, the agencies estimate that this program will lead to 199.2
million metric tons (MMT) of CO2 equivalent (CO2EQ) of annual GHG reduction and 14.9
billion gallons of fuel savings in the year 2050, as discussed in more detail in Chapter 5.
Chapter 6: Health and Environmental Impacts. This chapter discusses the health effects
associated with non-GHG pollutants, specifically: particulate matter, ozone, nitrogen oxides
(NOx), sulfur oxides (SOx), carbon monoxide and air toxics. These pollutants will not be
directly regulated by the standards, but the standards will affect emissions of these pollutants and
precursors. Reductions in these pollutants are the co-benefits of the rulemaking (that is, benefits
in addition to the benefits of reduced GHGs). This section discusses current and projected
concentrations of non-GHG pollutants as well as the air quality modeling methodology and
modeled projected impacts of this rule. This chapter also discusses GHG-related impacts, such
as changes in atmospheric CO2 concentrations, global mean temperature, sea level rise, and
ocean pH associated with the program's GHG emissions reductions.
Chapter 7: Vehicle-Related Costs of the Program. In this chapter, the agencies present
our estimate of the costs associated with the program. The presentation summarizes the costs
associated with new technology expected to be added to meet the GHG and fuel consumption
standards, including hardware costs to comply with the air conditioning (A/C) leakage program.
The analysis discussed in Chapter 7 provides our best estimates of incremental costs on a per
truck basis and on an annual total basis. We also present the fuel savings and maintenance costs
in this chapter, along with a detailed payback analysis for various vehicle segments.
Chapter 8: EPA's Economic and Other Impacts Analysis. This chapter provides EPA's
description of the net benefits of the HD National Program. To reach these conclusions, the
chapter discusses each of the following aspects of the analyses of benefits:
Rebound Effect. The VMT rebound effect refers to the fraction of fuel savings expected
to result from an increase in fuel efficiency that is offset by additional vehicle use.
Energy Security Impacts: A reduction of U.S. petroleum imports reduces both financial
and strategic risks associated with a potential disruption in supply or a spike in cost of a
particular energy source. This reduction in risk is a measure of improved U.S. energy security.

-------
Monetized GHG Impacts: The agencies estimate the monetized benefits of GHG
reductions by assigning a dollar value to reductions in GHG emissions using recent estimates of
the social cost of greenhouse gasses (SC-GHG). The SC-GHG is an estimate of the monetized
damages associated with an incremental increase in greenhouse gas emissions in a given year.
Other Impacts: There are other impacts associated with the GHG emissions and fuel
efficiency standards. Lower fuel consumption will, presumably, result in fewer gallons being
refilled and, thus, less time spent refueling. The increase in vehicle-miles driven due to a
positive rebound effect may also increase the societal costs associated with traffic congestion,
crashes, and noise. However, if drivers drive those additional rebound miles, there must be a
value to them which we estimate as the value of increased travel. The agencies also discuss the
impacts of safety standards and voluntary safety improvements on vehicle weight.
Chapter 8 also presents a summary of the total costs, total benefits, and net benefits
expected under the program.
Chapter 9: NHTSA and EPA considered the potential safety impact of technologies that
improve HD vehicle fuel efficiency and GHG emissions as part of the assessment of regulatory
alternatives. This chapter discusses the literature and research considered by the agencies, which
included two National Academies of Science reports, an analysis of safety effects of HD pickups
and vans using estimates from the DOT report on the effect of mass reduction and vehicle size
on safety, and agency-sponsored safety testing and research.
Chapter 10: NHTSA CAFE Model. This chapter describes NHTSA's CAFE modeling
system. The agencies used DOT's CAFE model to estimate manufacturer responses to these
standards for HD pickups and vans, and NHTSA also used the CAFE model to estimate emission
impacts for this sector.
Chapter 11: Results of Preferred and Alternative Standards. The heavy-duty truck
segment is very complex. The sector consists of a diverse group of impacted parties, including
engine manufacturers, chassis manufacturers, truck manufacturers, trailer manufacturers, truck
fleet owners and the public. The agencies have largely designed this program to maximize the
environmental and fuel savings benefits, taking into account the unique and varied nature of the
regulated industries. In developing this program, we considered a number of alternatives that
could have resulted in fewer or potentially greater GHG and fuel consumption reductions.
Chapter 9 Section summarizes the alternatives we considered.
Chapter 12: Small Business Flexibility Analysis. This chapter describes the agencies'
analysis of the small business impacts due to the joint program.
Chapter 13: Natural Gas Vehicles and Engines. This chapter describes EPA's lifecycle
analysis for natural gas used by the heavy-duty truck sector.

-------
Chapter 1: Industry Characterization
1.1	Introduction
The fuel consumption and CO2 emissions standards described in the Preamble of this
FRM will be applicable to three currently-regulated categories of heavy-duty vehicles: (1)
Combination Tractors; (2) Heavy-duty Pickup Trucks and Vans; and (3) Vocational Vehicles, as
well as spark-ignition and compression-ignition heavy-duty engines. The industry
characterization for these sectors can be found in the RIA for the HD Phase 1 rulemaking.1 With
this rulemaking, the agencies will be setting standards for combination trailers for the first time.
Also with this rulemaking, the agencies are setting standards that apply for small businesses for
the first time, as well as offering separate standards for vocational custom chassis. The
characterization laid out in this chapter focuses on trailers and vocational custom chassis,
whereas Chapter 12 of this RIA highlights impacts related to small businesses.
1.2	Trailers
A trailer is a vehicle designed to haul cargo while being pulled by another powered motor
vehicle. The most common configuration of large freight trucks consists of a Class 7 or 8 tractor
hauling one or more trailers. Vehicles in these configurations are called "combination tractor-
trailers" or simply "tractor-trailers." A trailer may be constructed to rest upon the tractor that
tows it, or be constructed so part of its weight rests on an auxiliary front axle called a "converter
dolly" between two or more trailers. Trailers are attached to tractors by a coupling pin (or king
pin) on the front of the trailer and a horseshoe-shaped coupling device called a fifth wheel on the
rear of the towing vehicle or on the converter dolly. A tractor can also pull international
shipping or domestic containers mounted on open-frame chassis, which when driven together on
the road function as trailers.
The Truck Trailer Manufacturers Association, an industry trade group primarily for
manufacturers of Class 7 and 8 truck trailers, offers publications of recommended practices,
technical bulletins and manuals that cover many aspects of trailer manufacture, and serves as a
liaison between the industry and government agencies.2 To date, federal regulations for the
trailer industry are limited to those issued by the Department of Transportation (See 49 CFR).
These regulations govern trailer dimensions and weight, as well as trailer safety requirements
(e.g., lights, reflective materials, bumpers, etc.). In addition, DOT requires that each trailer, like
other on-road vehicles, must have a Vehicle Identification Number (VIN).3 The VIN is
displayed on a label that is permanently-affixed to the trailer. It is required to contain the
manufacturer identification, make and type of vehicle, model year, type of trailer, body type,
length, and axle configuration. Trailer manufactures are responsible for reporting each trailer's
VIN information to NHTSA prior to the sale of the trailer.
1.2.1 Trailer Types
Class 7 and 8 tractors haul a diverse range of trailer types. The most common trailer type
is the box trailer, which is enclosed and can haul most types of mixed freight. The general
rectangular shape of these trailers allows operators to maximize freight volume within the

-------
regulated dimensional limits, since the majority of freight shipped by truck cubes-out (is volume-
limited) before it grosses-out (is weight-limited). Despite considerable improvements in
suspension, material, safety, durability, and other advancements, the basic shape of the box
trailer has not changed much over the past decades, although its dimensions have increased
incrementally from what used to be the industry's standard length of 40' to today's standard 53'
long van trailer. Today, box vans are commonly found in lengths of 28', 48', and 53'and widths
of 102" or 96." The 28' vans ("pups") are often driven in tandem and connected by a dolly.
Current length restrictions for the total combination tractor-trailer vehicle limit tandem operation
to 28' trailers. However, some members of the trucking industry are pushing to increase the
length limits to allow trailers as long as 33' to be pulled in tandem, and arguing that these "less
than truckload" (LTL) operations could increase capacity per truckload, reduce the number of
trucks on the road, reduce the fuel consumption and emissions of these tractor-trailers, and
remain within the current weight limits.4,5
Trailers are often highly customized for each order. The general structure of the box
trailer type is common and consists of vertical support posts in the interior of the trailer covered
by a smooth exterior surface. However the exterior of the trailer may be constructed of
aluminum or a range of composite materials. Historically, floors were constructed of wood,
however many trailer customers are requesting aluminum floors to reduce weight. Semi-trailer
axles are commonly a dual tandem configuration, but can also be single, spread tandem (i.e., two
axles separated to maximize axle loads), tridem (i.e., three axles equally spaced), tri axles (i.e.,
three axles consisting of a tandem and a third axle that may be liftable), or multi-axles to
distribute very heavy loads. Axles can be fixed in place, or allowed to slide to adjust weight
distribution. Doors are commonly located at the rear of the trailer. The most common door is
the side-by-side configuration, in which each door opens outward. Roll-up doors, which are
more costly, allow truck drivers to pull up to loading docks without first stopping to open the
doors. Roll-up doors are common on trailers with temperature-sensitive freight. Additional
variations in trailers include side-access doors, or use the underside of the trailer for belly boxes
or to store on-demand items such as ladders or spare tires.
The most common box trailer is the standard dry van, which transports cargo that does
not require special environmental conditions. In addition to the standard rectangular shape, dry
vans come in several specialty variants, such as drop floor, expandable, and curtain-side.
Another type of specialty box trailer is the refrigerated van trailer (reefer). This is an enclosed,
insulated trailer that hauls temperature sensitive freight, with a transportation refrigeration unit
(TRU) or heating unit mounted in the front of the trailer powered by a small (9-36 hp) diesel
engine. Figure 1-1 shows an example of the standard dry and refrigerated van.

-------
Adapted from http://www.wbmcguire.com/links/Guides/TruckTrailerGuide.pdf
Figure 1-1 Example of Dry and Refrigerated Van
Many other trailer types are uniquely designed to transport a specific type of freight.
Platform trailers carry cargo that may not be easily contained within or loaded and unloaded into
a box trailer, such as large, non-uniform equipment or machine components. Platforms come in
different configurations including standard flatbed, gooseneck, and drop deck. Tank trailers are
pressure-tight enclosures designed to carry liquids, gases or bulk, dry solids and semi-solids.
Tank trailers are generally constructed of steel or aluminum. The plumbing for intake and
discharge of the contents could be located below the tank or at the rear. There are also a number
of other specialized trailers such as grain (with and without hoppers), dump (frameless, framed,
bottom dump, demolition), automobile hauler (open or enclosed), livestock trailers (belly or
straight), construction and heavy-hauling trailers (tilt bed, hydraulic).
A sizable fraction of U.S. freight is transported in large, steel containers both
internationally via ocean-going vessels and domestically via rail cars. Containers are constructed
with steel sidewalls and external support beams, which results in a corrugated exterior. These
containers haul mixed freight and are designed with similar dimensions to box trailers. Ocean-
going international shipping containers are typically 20-feet or 40-feet in length. Domestic
containers, which often travel by rail, are 53-feet in length. Transport of these containers from
ports or rail to their final destination requires the container to be loaded on a specialty piece of
equipment called a chassis. The chassis, which is attached to the fifth wheel of a Class 7 or 8
tractor, consists of a frame, axles, suspension, brakes and wheel assemblies, as well as lamps,
bumpers and other required safety components. Fixed chassis vary in length according to the
type of container that will be attached, though some chassis adjust to accommodate different
sizes. When the chassis and container are assembled the unit serves the same function as a road
trailer.6 However, under customs regulations, the container itself is not considered part of a road
vehicle.7
ACT Research compiles factory shipment information from a Trailer Industry Control
Group that represents 80 percent of the U.S. trailer industry. Figure 1-2 shows the distribution of
trailers sold in the U.S. based on ACT Research's 2013 factory shipment data. The most
common type of trailer in use today is the dry van trailer, followed by the refrigerated van.
Together, these box vans make up greater than 70 percent of the industry. Trailer Body

-------
Builders' annual trailer output report estimates there were over 240,000 trailers sold in North
America 2013.
ACT Research 2013 Factory Shipments
4% 1 %
ฆ	Dry Van
ฆ	Refrigerated Van
ฆ	Platform
ฆ	HeavyLowbed
ฆ	MediumLowbed
ฆ	Dump
ฆTankLiquid
ฆTank Bulk
Grain
Other Trailer
Chassis
Figure 1-2 ACT Research's 2013 U.S. factory shipments
1.2.2 Trailer Manufacturers
The diverse van, platform, tank and specialty trailers are produced by a large number of
trailer manufacturers. EPA estimates there are 178 trailer manufacturers. Trailers are far less
mechanically complex than the tractors that haul them, and much of trailer manufacturing is
done by hand. This relatively low barrier to entry for trailer manufacturing accounts, in part, for
the large number of trailer manufacturers. Figure 1-3 shows the production distribution of the
industry for the top 28 companies.8 While the percentages and ranking vary slightly year-to-
year, the top five manufacturers consistently produce over 70 percent of the manufacturing
output of the industry.
Trailer Body Builders 2015 North American Truck Trailer Output Report
(339,948 Total Trailers)
ฆ	Wabash National Corporation
ฆ	Great Dane Limited Partnership
ฆ	Hyundai Translead
ฆ	Utility Trailer Manufacturing
ฆ	Vanguard National Trailer/CIMC
ฆ	Stoughton Trailers LLC*
ฆ	Manac
ฆ	Fontaine Trailer Company
ฆ	Wilson Trailer Company
ฆ	MAC Trailer Manufacturing
ฆ	Heil Trailer International, Co.
s Strick Corporation*
Pitts Enterprises*
Timpte Inc.*
Reitnouer Inc.*
Next 13 Companies (None > 1.0%) **
Small business according to SBA definition of <1000 employees
* 9 of 13 are small businesses
Figure 1-3 2015 Trailer Output Report from Trailer Body Builders

-------
Table 1-1 illustrates the varying revenue among trailer manufacturers and further
distinguishes the very different roles in that market played by small and large manufacturers.
The revenue numbers were obtained from Hoovers online company database.9 Over 80 percent
of trailer manufacturers meet the Small Business Administration's (SB A) definition of a small
business (i.e., less than 1,000 employees), yet these manufacturers make up less than 25 percent
of the overall revenue from the industry. In fact, a majority of the small business trailer
manufacturers make less than $10 million in revenue per year.
Table 1-1 Summary of 2014 Trailer Industry Revenue by Business Size
REVENUE RANGE
BUSINESS SIZE
All Sizes
Large
Small3
> 1000M
3
3
0
$500M - $999M
2
2
0
$400M - $499M
1
1
0
$300M - $399M
3
3
0
$200M - $299M
5
4
1
$100M - $199M
3
1
2
$50M - $99M
14
6
8
$40M - $49M
22
2
20
$15M - $19M
8
0
8
$10M - $14M
17
3
14
$5M - $9M
35
4
31
< $5M
65
2
63




Total Companies
178
31
147
Total Revenue ($M)
10841
8543
2298
Average Revenue ($M)
61
276
16




Box Trailer Mfrs
13
8
5
Non-Box Trailer Mfrs
173
29
144
Note:
a The Small Business Administration (SB A) defines a trailer
manufacturer as a "small business" if it has fewer than 1,000
employees
The trailer industry was particularly hard hit by the recent recession. Trailer
manufacturers saw deep declines in new trailer sales of 46 percent in 2009; some trailer
manufacturers saw sales drop as much as 71 percent. This followed overall trailer industry
declines of over 30 percent in 2008. The 30 largest trailer manufacturers saw sales decline 72
percent from 282,750 in 2006, to only 78,526 in 2009. Several trailer manufacturers shut down
entire production facilities and a few went out of business altogether. Trailer production has
steadily grown across the industry since 2010 and, although historic production peaks have not
been repeated to date, it has now returned to levels close to those seen in the mid-2000s. Figure
1-4 shows the ACT Research's annual factory shipments, which illustrates the unsteady
production over the past 17 years. Trailer Body Builders' annual trailer output report estimates
there were over 240,000 trailers sold in North America in 2013. Output increased to 292,000 in
2014 and to nearly 340,000 in 2015 (very close to the current record from 1999).

-------
ACT Research Annual Factory Shipments
400000 -|
350000 -
300000 -
250000 -
200000 -
150000
5 ~ 100000
W
c
QJ -
fc Q)
Q. Q.
I/) "3
^ 0)
5 TO
u ฃ
(0
50000
CD N- CO O)
0)0)0)0)
O) O) O) O)
O (M CO lO CD
oooooooo
oooooooo
00 O) o
o O T— -rr
O O O o o o
(NfM(M(NCM(NCM(N(N(N(NtNCNjf\|
Figure 1-4 Annual Factory Shipments Tracked by ACT Research
1.2.3 Trailer Use
In order to determine the appropriate tractor type for each trailer, the agencies
investigated "primary trip length" results from the Vehicle Inventory and Use Survey database
to determine the distribution of trailers in short- and long-haul applications.10 Using a primary
trip length of 500 miles or less to represent short-haul use, the agencies found that, of the
reported vehicles, over 50 percent of the 53-feet and longer dry vans were used in long-haul and
over 80 percent of the shorter vans were used in short-haul applications. Over 70 percent of the
reported 53-feet and longer refrigerated vans were long-haul trailers, with 65 percent of the
shorter refrigerated vans used in short-haul applications. The survey found that non-box trailers
are most frequently used for short-haul. Figure 1-5 summarizes these findings.
U.S. Census 2002 Vehicle Inventory and Use Survey
Tractor-Trailer Primary Trip Length
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
53'+ Dry Van 53'+ Reefer <53' Dry Van <53' Reefer
Flatbed, Tank {Dry Bulk) Tank (Liquid,
Platform,	Gases)
Curtainside, etc
ฆ Short-Haul (<500 mi) ฆLong-Haul
Figure 1-5 2002 Vehicle Inventory and Use Survey Considering Primary Trip Length for Tractor-Trailers

-------
Truck drivers and trucking fleets frequently do not control all or even any of the trailers
that they haul. Trailers can be owned by freight customers, large equipment leasing companies,
third party logistics companies, and even other trucking companies. Containers on chassis,
which function as trailers, are rarely owned by truck operators. Rather, they are owned or leased
by ocean-going shipping companies, port authorities or others. This distinction between who
hauls the freight and who owns the equipment in which it is hauled means that truck owners and
operators have limited ability to be selective about the trailers they carry, and very little incentive
or ability to take steps to reduce the fuel use of trailers that they neither own or control.
For refrigerated trailers, the story is slightly different. These trailers are used more
intensely and accumulate more annual miles than other trailers. Over time, refrigerated trailers
can also develop problems that interfere with their ability to keep freight temperature-controlled.
For example, the insulating material inside a refrigerated trailer's walls can gradually lose its
thermal capabilities due to aging or damage from forklift punctures. The door seals on a
refrigerated trailer can also become damaged or loose with age, which greatly affects the
insulation characteristics of the trailer, similar to how the door seal on a home refrigerator can
reduce the efficiency of that appliance. As a result of age-related problems and more intense
usage, refrigerated trailers tend to have shorter procurement cycles than dry van trailers, which
means a faster turnover rate, although still not nearly as fast as for trucks in their first use.
Tractor-trailers are often used in conjunction with other modes of transportation (e.g.,
shipping and rail) to move goods across the country, known as intermodal shipping. Intermodal
traffic typically begins with containers carried on ships, and then they are loaded onto railcars,
and finally transported to their end destination via truck. Trucks that are used in intermodal
applications are of two primary types. Trailer-on-flatcar (TOFC) involves lifting the entire
trailer or the container attached to its chassis onto the railcar. In container-on-flatcar (COFC)
applications, the container is removed from the chassis and placed directly on the railcar. The
use of TOFCs allows for faster transition from rail to truck, but is more difficult to stack on a
vessel; therefore the use of COFCs has been increasing steadily. Both applications are used
throughout the U.S. with the largest usage found on routes between West Coast ports and
Chicago, and between Chicago and New York.
1.2.4 Trailer Fleet Size Relative to the Tractor Fleet
In 2013, over 800,000 trailers were owned by for-hire fleets and almost 300,000 were
owned by private fleets. Trailers that are purchased by fleets are typically kept much longer than
are the tractors, so trucks and trailers have different purchasing cycles. Also, many trailers are
owned by shippers or by leasing companies, not by the trucking fleets. Because of the
disconnect between owners and operators, the trailer owners may not benefit directly from fuel
consumption and GHG emission reductions.
The industry generally recognizes that the ratio of the number of dry van trailers in the
fleet relative to the number of tractors is typically three-to-one.11 Typically at any one time, two
trailers are parked while one is being transported. Certain private fleets may have ratios as high
as six-to-one and owner-operators may have a single trailer for their tractor. The ratio of
refrigerated vans to tractors is closer to two-to-one. This is partly due to the fact that it is more
expensive to purchase and operate refrigerated vans compared to dry vans. Specialty trailers,

-------
such as tanks and flatbeds are often attached to a single trailer throughout much of their life.
This characteristic of the trailer fleet impacts the cost effectiveness of trailer technologies. The
annual savings achieved due to these technologies are proportional to the number of miles
traveled in a year and the analysis for many of the trailers must account for some amount of
inactivity, which will reduce the benefits.
1.3 Vocational Vehicles: Custom Chassis
Based on public comments, information on entities who have certified, and stakeholder
outreach, we have deepened our understanding of the vocational vehicle market, including the
nature of specialization vs diversification among vocational vehicle manufacturers. We have
identified seven vocations as shown in Table 1-2, for which there are manufacturers who are not
diversified in their products competing for sales with diversified manufacturers. We are calling
these custom chassis in this rulemaking.
Table 1-2 Diversification of Vocational Chassis Manufacturers"
Vehicle Type
Number of Single-type
Chassis Manufacturers
Number of Multiple-type
Chassis Manufacturers
Coach (Intercity) Bus
2
3
Motor Home
3
8
School Bus
1
2
Transit Bus
4
4
Refuse Truck
1
6
Cement Mixer
2
7
Emergency Vehicle
6
7
Note:
a Includes U.S.-made vehicles and those imported for sale in the U.S.
The diversity of vocational vehicles also includes applications such as terminal tractors,
street sweepers, concrete pumpers, asphalt blasters, aircraft deicers, sewer cleaners, mobile
medical clinics, bookmobiles, and mobile command centers. Most of these are produced by
manufacturers of the vehicles listed in Table 1-2, while some are produced by small, specialized
companies.
In terms of total production volume, Table 1-3 summarizes what we know about the sales
of the seven custom chassis vehicle types. Of the other miscellaneous vehicles, the ones
produced in the highest volume are the terminal tractors, at about 6,000 per year (including those
certified with nonroad engines), with typical annual miles of less than 10,000 miles per year.12

-------
Table 1-3 Custom Chassis Population Estimates
APPLICATION TYPE
PERCENT OF NEW MY 2018
VOCATIONAL POPULATION
AVERAGE VMT IN
FIRST YEAR
Coach (Intercity) Bus
1%
85,000
Motor Home
13%
2,000
School Bus
10%
14,000
Transit Bus
1%
64,000
Refuse Truck
3%
34,000
Cement Mixer b
1%
20,000
Emergency Vehicle 0
1%
6,000
Notes:
1:1 Source: MOVES 2014 for all except mixer and emergency.A
b Source for cement mixer is UCS13
0 Source for emergency is ICCT (2009)14 and FAMA (2004)15
A Vehicle populations are estimated using MOVES2014. More information on projecting populations in MOVES is
available in the following report: USEPA (2015). "Population and Activity of On-road Vehicles in MOVES2014 -
Draft Report" Docket No. EPA-HQ-OAR-2014-0827.

-------
References
1	U.S. EPA and NHTSA, 2011. Regulatory Impact Analysis for the Final Rulemaking to Establish Greenhouse Gas
Emissions Standards and Fuel Efficiency Standards for Medium and Heavy-Duty Engines and Vehicles. EPA-420-
R-l 1-901. Available at: http://www3.epa.gov/otaq/climate/documents/420rll901.pdf.
2	http://www.ttmanet.org.
3	49 CFR 565.
4	"Both Sides of Truck Weight, Size Gear Up for Next Battle." Szakonyi, Mark. February 25, 2014. Available at:
http://www.joc.com/regulation-policy/transportation-policy/us-transportation-policy. Accessed: August 18, 2014.
5	"Wabash Shows What a 33-Foot Pup Would Look Like." Berg, Tom. Heavy-Duty Trucking TruckingInfo.com.
March 31, 2014. Available at: www.truckinginfo.com/blog/trailer-talk/story/2014/03/wabash-shows-what-a-33-
foot-pup-would-look-like.aspx. Accessed: September 23, 2014.
6	Per 46 CFR ง 340.2.
7	19 CFR 115.3.
8	Trailer-BodyBuliders. North American Trailer Output Report, 2015 Trailer Production Figures Table. Available
online at: http://trailer-bodybuilders.com/trailer-output/2015-trailer-production-figures-table.
9	Dun & Bradstreet. Hoover's Inc. Online Company Database. Available at: http://www.hoovers.com.
10	U.S. Census Bureau. 2002 Economic Census - Vehicle Inventory and Use Survey. 2002. Available at:
https://www.census.gov/prod/ec02/ec02tv-us.pdf.
11	TIAX. LLC. "Assessment of Fuel Economy Technologies for Medium- and Heavy-Duty Vehicles," Final Report
to the National Academy of Sciences, November 19, 2009. Page 4-49.
12	See Charged Magazine, 2012 article, https://chargedevs.com/features/find-your-ninche-balqon-corporation-
targets-short-haul-drayage-tractors/, accessed April 2016.
13	National Ready Mixed Association Fleet Benchmarking and Costs Survey,
http://www.nxtbook.eom/naylor/NRCQ/NRCQ0315/index.php#/22, fromUCS Custom Chassis Recommendations,
May 2016.
14ICCT, May 2009, "Heavy-Duty Vehicle Market Analysis: Vehicle Characteristics & Fuel Use, Manufacturer
Market Shares."
15 Fire Apparatus Manufacturer's Association, Fire Apparatus Duty Cycle White Paper, August 2004, available at
http://www.deepriverct.us/firehousestudy/reports/Apparatus-Duty-Cycle.pdf.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Chapter 2: Technology and Cost
2.1 Overview of Technologies
In discussing the potential for CO2 emission and fuel consumption reductions, it can be
helpful to think of the work flow through the system. The initial work input is fuel. Each gallon
of fuel has the potential to produce some amount of work and will produce a set amount of CO2
(about 22 pounds (10 kg) of CO2 per gallon of diesel fuel). The engine converts the chemical
energy in the fuel to useable work to move the truck. Any reductions in work demanded of the
engine by the vehicle or improvements in engine fuel conversion efficiency will lead directly to
CO2 emission and fuel consumption reductions.
Current diesel engines are around 40 percent efficient over a range of operating
conditions depending on engine sizes and applications, while gasoline engine efficiency is much
lower than that of diesel engines. This means that approximately one-third of the fuel's chemical
energy is converted to useful work and roughly two-thirds is lost to friction, gas exchange, and
waste heat in the coolant and exhaust. In turn, the truck uses this work delivered by the engine to
overcome overall vehicle-related losses such as aerodynamic drag, tire rolling resistance, friction
in the vehicle driveline, and to provide auxiliary power for components such as air conditioning
and lights. Lastly, the vehicle's operation, such as vehicle speed and idle time, affects the
amount of total energy required to complete its activity. While it may be intuitive to look first to
the engine for CO2 emission and fuel consumption reductions given that only about one-third of
the fuel is converted to useable work, it is important to realize that any improvement in vehicle
efficiency proportionally reduces both the work demanded and the energy wasted.
Technology is one pathway to improve heavy-duty truck GHG emissions and fuel
consumption. Near-term solutions exist, such as those being deployed by SmartWay partners in
heavy-duty truck long haul applications. Other solutions are currently under development and
being implemented in the light-duty vehicle segment, especially in the large pickup sector where
some of the technologies apply to the heavy-duty pickup trucks covered under this rulemaking.
Long-term solutions are currently under development to improve efficiencies and cost-
effectiveness. While there is not a "silver bullet" that will significantly eliminate GHG
emissions from heavy-duty trucks like the catalytic converter has for criteria pollutant emissions,
significant GHG and fuel consumption reductions can be achieved through a combination of
engine, vehicle system, and operational technologies.
The following sections will discuss technologies in relation to each of the regulatory
categories - Heavy-Duty Pickup Trucks and Vans, Heavy-Duty Engines, Class 7 and 8
Combination Tractors, Trailers, and Class 2b-8 Vocational Vehicles. In each of these sections,
information on technological approaches, costs, and percent improvements is provided.
Depending on the segment, the vehicle-level technologies available for consideration may
include idle reduction, improved tire rolling resistance, improved transmissions, improved axles,
weight reduction, improved accessories, and aerodynamic technologies. Depending on the
segment, the engine-level technologies available for consideration may include friction
reduction, variable valve timing, cylinder deactivation, turbocharging, downsizing, combustion
optimization, aftertreatment optimization, and waste heat recovery. The agencies are not

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
projecting that all of the technologies discussed in these sections would be used for compliance
with the engine and vehicle standards, for reasons that are also discussed in each section.
Nevertheless, the potential for there to be technologies other than those which form the basis for
the compliance pathway set forth by the agencies, or which can be used in different combinations
or penetration rates than that projected compliance pathway, is an important consideration in
assessing the feasibility of the standards. Summaries of all of the technologies, along with the
corresponding costs, fuel consumption and GHG emissions improvement percentages are
provided in this chapter. This chapter also describes the agencies' basis for determining
penetration rates for the various technologies for each of the respective regulatory subcategories.
Summaries of engine technologies, effectiveness, and costs are provided in Chapters 2.2, 2.3,
2.6, and 2.7. A summary of engine and vehicle technologies, effectiveness, and costs for HD
pickup trucks and vans is provided in Chapter 2.5. A summary of technologies, effectiveness,
and costs for tractors is provided in Chapter 2.8. A summary of technologies, effectiveness, and
costs for vocational vehicles is provided in Chapter 2.9. A summary of technologies,
effectiveness, and costs for trailers is provided in Chapter 2.10. A detailed analysis of
technology costs is found in Chapters, 2.11 and 2.12.
EPA and NHTSA collected information on the cost and effectiveness of fuel
consumption and CO2 emission reducing technologies from several sources. The primary
sources of information were the 2010 National Academy of Sciences report on Technologies and
Approaches to Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles (NAS)1,
TIAX's assessment of technologies to support the NAS panel report (TIAX)2, EPA's Heavy-
Duty Lumped Parameter Model3, the analysis conducted by NESCCAF, ICCT, Southwest
Research Institute and TIAX for reducing fuel consumption of heavy-duty long haul combination
tractors (NESCCAF/ICCT)4, and the technology cost analysis conducted by ICF for EPA (ICF).5
In addition, the agencies relied on NHTSA's technology assessment report under contract with
SwRI and Tetra Tech.6'7'8 We also held many meetings with engine and vehicle OEMs and
received information from comment to the notice of proposed rulemaking that further informed
our decision making process. In addition, the agencies used the vehicle simulation model (the
Greenhouse gas Emissions Model or GEM) to quantify the effectiveness of various technologies
on CO2 emission and fuel consumption reductions in terms of vehicle performance. These
values were used, in turn, to calculate standard stringency of all standards where GEM is used in
determining ultimate compliance. Thus, in all instances where GEM is used for compliance, it
was also used in determining standard stringency. The simulation tool is described in RIA
Chapter 4 in more detail.
2.2 Technology Principles - SI Engines
The engine technology principles described in this chapter for SI and CI engines are
typically described as applying for gasoline and diesel-fueled engines, respectively. Even so,
these technology principles generally also apply for engines powered by other fuels, including
natural gas. In Section II of the Preamble to these rules, the agencies describe regulatory
provisions that differ between SI and CI engines. Technologies related to closed crankcases for
natural gas engines are described below in Chapter 2.11 and in the Preamble Section XI.B.2.d.
The agencies describe technologies and test procedures related to minimizing evaporative
emissions from natural gas fuel systems in Chapter 2.11 as well as in Section XI.B.2.f of the
Preamble to these rules. The agencies' approach in this document is to first describe the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
principles of how technologies can work for an engine, without specifying the type of vehicle
into which it will be installed, or the test cycle over which it will be certified. Later, in Chapter
2.5, the agencies describe a subset of these technologies as they apply specifically to complete
HD pickup trucks and vans over their applicable operation and test cycles. In Chapter 2.6, the
agencies describe a subset of these technologies as they apply to SI engines intended for
vocational vehicles. The effectiveness values described in this section are ranges that cover SI
and CI engines in general and will differ between vocational vehicles which are engine certified
and HD pickup trucks and vans which are chassis certified. The effectiveness ranges represent
expected levels of effectiveness with appropriate implementation of the technology but actual
effectiveness levels will vary with manufacturer specific design and specifications for the
technologies. These may include considerations for durability or other related constraints. The
agencies did not receive comments disputing the expected technology effectiveness values
reported in the NPRM.
2.2.1	Engine Friction Reduction
In addition to low friction lubricants, manufacturers can reduce friction and improve fuel
consumption by improving the design of engine components and subsystems. Examples include
improvements in low-tension piston rings, piston skirt design, roller cam followers, improved
crankshaft design and bearings, material coatings, material substitution, more optimal thermal
management, and piston and cylinder surface treatments. The 2010 NAS Report, NESCCAF9
and EEA10 reports as well as confidential manufacturer data used in the both the light-duty and
this heavy-duty vehicle rulemaking suggest a range of effectiveness for engine friction reduction
to be between 1 to 3 percent. Reduced friction in bearings, valve trains, and the piston-to-liner
interface would improve efficiency. Any friction reduction must be carefully developed to avoid
issues with durability or performance capability.
2.2.2	Variable Valve Timing
Variable valve timing (VVT) classifies a family of valve-train designs that alter the
timing of the intake valve, exhaust valve, or both, primarily to reduce pumping losses, increase
specific power, and control the level of residual gases in the cylinder. VVT reduces pumping
losses when the engine is lightly loaded by controlling valve timing closer to the optimum
needed to sustain horsepower and torque. VVT can also improve volumetric efficiency at higher
engine speeds and loads. Additionally, VVT can be used to alter (and optimize) the effective
compression ratio where it is advantageous for certain engine operating modes (e.g., in the
Atkinson Cycle).
VVT has now become a widely adopted technology in the light duty fleet and this
technology is readily adaptable to the heavy-duty fleet: in MY 2014, most of all new cars and
light trucks had engines with some method of variable valve timing.11 There are currently many
different types of variable valve timing being utilized by Manufacturers, which have a variety of
different names and methods. The three major types of VVT are listed below.
Each implementation of VVT uses a cam phaser to adjust the camshaft angular position
relative to the crankshaft position, referred to as "camshaft phasing." This phase adjustment
results in changes to the pumping work required by the engine to accomplish the gas exchange

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
process. The majority of current cam phaser applications use hydraulically-actuated units,
powered by engine oil pressure and managed by a solenoid that controls the oil pressure supplied
to the phaser.
2.2.2.1	Coupled Cam Phasing for Overhead Valve (OHV) and Single Overhead
Camshaft (SOHC) Engines
Valvetrains with coupled (or coordinated) cam phasing (CCP) can modify the timing of
both the inlet valves and the exhaust valves an equal amount by varying the phasing of the
camshaft across an engine's range of operating speeds; also known as VVT. For engines
configured as an overhead valve (OHV) or as a single overhead camshaft (SOHC) only one cam
phaser is required per camshaft to achieve CCP.
Based on the heavy-duty Phase 1 vehicle rulemaking, 2015 NHTSA Technology Study,
and previously-received confidential manufacturer data, the agencies estimate the fuel
consumption reduction effectiveness of this technology to be between 1 and 3 percent for heavy-
duty applications across the different test cycles and operational opportunities.
2.2.2.2	Intake Cam Phasing (ICP) for Dual Overhead Camshaft Engines
(DOHC)
Valvetrains with ICP, which is the simplest of the cam phasing technologies, can modify
the timing of the inlet valves by phasing the intake camshaft while the exhaust valve timing
remains fixed. This requires the addition of a cam phaser on each bank of intake valves on the
engine. An in-line 4-cylinder engine has one bank of intake valves, while V-configured engines
have two banks of intake valves.
Some newer Class 2b and 3 market entries are offering dual overhead camshaft (DOHC)
engine designs where two camshafts are used to operate the intake and exhaust valves
independently. Consistent with the heavy-duty 2014-2018 MY vehicle rulemaking and the SwRI
report, the agencies agree with the effectiveness values of 1 to 2 percent reduction in fuel
consumption for heavy-duty applications across the different test cycles and operational
opportunities, for this technology.
2.2.2.3	Dual Cam Phasing (DCP) for Dual Overhead Camshaft Engines
(DOHC)
The most flexible VVT design is dual (independent) cam phasing, where the intake and
exhaust valve opening and closing events are controlled independently. This option allows the
option of controlling valve overlap, which can be used as an internal EGR strategy. At low
engine loads, DCP creates a reduction in pumping losses, resulting in improved fuel
consumption. Increased internal EGR also results in lower engine-out NOx emissions. The
amount by which fuel consumption is improved depends on the residual tolerance of the
combustion system. Additional improvements are observed at idle, where low valve overlap
may result in improved combustion stability, potentially reducing idle fuel consumption. DCP
requires two cam phasers on each bank of the engine.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Some newer Class 2b and 3 market entries are offering dual overhead camshaft (DOHC)
engine designs where two camshafts are used to operate the intake and exhaust valves
independently. Consistent with the light-duty 2012-2016 MY vehicle rulemaking and the SwRI
report, the agencies agree with the effectiveness values of 1 to 3 percent reduction in fuel
consumption for heavy-duty applications across the different test cycles and operational
opportunities for this technology.
2.2.2.4	Variable Valve Lift (VVL)
Controlling the lift of the valves provides a potential for further efficiency improvements.
By optimizing the valve-lift profile for specific engine operating regions, the pumping losses can
be reduced by reducing the amount of throttling required to produce the desired engine power
output. By moving the throttling losses further downstream of the throttle valve, the heat
transfer losses that occur from the throttling process are directed into the fresh charge-air mixture
just prior to compression, delaying the onset of knock-limited combustion processes. Variable
valve lift control can also be used to induce in-cylinder mixture motion, which improves fuel-air
mixing and can result in improved thermodynamic efficiency. Variable valve lift control can
also potentially reduce overall valvetrain friction. At the same time, such systems may also incur
increased parasitic losses associated with their actuation mechanisms. A number of
manufacturers have already implemented VVL into their fleets (Toyota, Honda, and BMW), but
overall this technology is still available for most of the fleet. There are two major classifications
of variable valve lift, described below:
2.2.2.5	Discrete Variable Valve Lift (DVVL)
Discrete variable valve lift (DVVL) systems allow the selection between two or three
discrete cam profiles by means of a hydraulically-actuated mechanical system. By optimizing
the cam profile for specific engine operating regions, the pumping losses can be reduced by
reducing the amount of throttling required to produce the desired engine power output. This
increases the efficiency of the engine. These cam profiles consist of a low and a high-lift lobe,
and may include an inert or blank lobe to incorporate cylinder deactivation (in the case of a 3-
step DVVL system). DVVL is normally applied together with VVT control. DVVL is also
known as Cam Profile Switching (CPS). DVVL is a mature technology in LD applications with
low technical risk.
Based on the light-duty MY 2017-2025 final rule, previously-received confidential
manufacturer data, 2015 NHTSA Technology Study, and report from the Northeast States Center
for a Clean Air Future (NESCCAF), the agencies estimate the fuel consumption reduction
effectiveness of this technology to be between 1 and 3 percent for heavy-duty applications across
the different test cycles and operational opportunities.
2.2.3 Cylinder Deactivation
In conventional spark-ignited engines throttling the airflow controls engine torque output.
At partial loads, efficiency can be improved by using cylinder deactivation instead of throttling.
Cylinder deactivation can improve engine efficiency by disabling or deactivating (usually) half
of the cylinders when the load is less than half of the engine's total torque capability - the valves

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
are kept closed, and no fuel is injected - as a result, the trapped air within the deactivated
cylinders is simply compressed and expanded as an air spring, with reduced friction and heat
losses. The active cylinders combust at almost double the load required if all of the cylinders
were operating. Pumping losses are significantly reduced as long as the engine is operated in
this "part cylinder" mode. Effectiveness improvements scale roughly with engine displacement-
to-vehicle weight ratio: the higher displacement-to-weight vehicles, operating at lower relative
loads for normal driving, have the potential to operate in part-cylinder mode more frequently.
Cylinder deactivation is less effective on heavily-loaded vehicles because they require more
power and spend less time in areas of operation where only partial power is required. The
technology also requires proper integration into the vehicles which is difficult in the vocational
vehicle segment where often the engine is sold to a chassis manufacturer or body builder without
knowing the type of transmission or axle used in the vehicle or the precise duty cycle of the
vehicle. The cylinder deactivation requires fine tuning of the calibration as the engine moves
into and out of deactivation mode to achieve acceptable NVH. Additionally, cylinder
deactivation would be difficult to apply to vehicles with a manual transmission because it
requires careful gear change control. NHTSA and EPA adjusted the 2017-2025 MY light-duty
rule estimates using updated power to weight ratings of heavy-duty trucks and confidential
business information and downwardly adjusted the effectiveness to 0 to 3 percent over average
driving patterns for these vehicles to reflect the differences in drive cycle and operational
opportunities compared to light-duty vehicles.
2.2.4 Stoichiometric Gasoline Direct Injection (SGDI)
Stoichiometric gasoline direct injection (SGDI) engines inject fuel at high pressure
directly into the combustion chamber (rather than into the intake port in port fuel injection).
SGDI requires changes to the injector design, an additional high pressure fuel pump, new fuel
rails to handle the higher fuel pressures, and changes to the cylinder head and piston crown
design. Direct injection of the fuel into the cylinder improves cooling of the air/fuel charge
within the cylinder, which allows for higher compression ratios and increased thermodynamic
efficiency without the onset of combustion knock. Recent injector design advances, improved
electronic engine management systems and the introduction of multiple injection events per
cylinder firing cycle promote better mixing of the air and fuel, enhance combustion rates,
increase residual exhaust gas tolerance, and improve cold start emissions. SGDI engines achieve
higher power density and match well with other technologies, such as boosting and variable
valvetrain designs.
Several manufacturers have recently introduced vehicles with SGDI engines, including
GM and Ford, who have announced their plans to increase dramatically the number of SGDI
engines in their vehicle portfolios.
Based on the heavy-duty 2014-2018 MY vehicle rulemaking, the 2015 NHTSA
Technology Study, and previously-received confidential manufacturer data, the agencies
estimate the fuel consumption reduction effectiveness of SGDI to be between 1 and 2 percent for
heavy-duty applications across the different test cycles and operational opportunities.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.2.5 Turbocharging and Downsizing (TRBDS)
The specific power of a naturally aspirated engine is primarily limited by the rate at
which the engine is able to draw air into the combustion chambers. Turbocharging and
supercharging (grouped together here as boosting) are two methods to increase the intake
manifold pressure and cylinder charge-air mass above naturally aspirated levels. Boosting
increases the airflow into the engine, thus increasing the specific power level, and with it the
ability to reduce engine displacement while maintaining performance. This effectively reduces
the pumping losses at lighter loads in comparison to a larger, naturally aspirated engine.
Almost every major manufacturer offering both light-duty and heavy-duty vehicles,
including 2b/3s, currently markets vehicles in their light-duty offerings with some form of
boosting. Only one manufacturer, Ford, has allowed the light-duty derived boosted engine to
migrate into its 2b/3 van offering. The ability to use a smaller boosted engine is currently limited
to applications where operational duty cycles are more consistent with light-duty vehicles of
similar utility like full size pick-ups and MDPVs. The Ford 2b/3 van has similar capability as
the light-duty pick-up from which the boosted engine is borrowed. In applications that require
high payload or towing capacity that substantially exceeds the light-duty ranges of towing
capacity, manufacturers have chosen to maintain the larger displacement non-boosted engines
because of the boosted engine's loss of effectiveness when performing towing. In their
comments, AAPC illustrated this issue showing that downsized and boosted engines actually
perform worse from a brake specific fuel consumption perspective when encountering high
loads, such as towing, than a traditional non-boosted engine of more historical displacements.
Class 4 and higher vocational vehicles have not employed any form of boosted and downsized
engines because of this penalty. In our projected compliance pathways for pickups and vans, the
agencies are projecting use of a smaller boosted engine only where suited to a 2b/3 vehicle's
duty cycles - reflecting current industry practice. This approach properly targets GHG and fuel
consumption reductions to the expected vehicle duty cycles and provides a balance based on the
consumer's requirements of their work vehicle.
While boosting has been a common practice for increasing performance for several
decades in light-duty vehicles, turbocharging has considerable potential to improve fuel economy
and reduce CO2 emissions when the engine displacement is also reduced. Specific power levels
for a boosted engine often exceed 100 hp/L, compared to average naturally aspirated engine
power densities of roughly 70 hp/L. As a result, engines can be downsized roughly 30 percent or
higher while maintaining similar peak output levels. However, as just discussed above, the
effectiveness of boosted and downsized engines is a function of duty cycle and may not be
appropriate for some applications encountering regular high loads such as towing. In the last
decade, improvements to turbocharger turbine and compressor design have improved their
reliability and performance across the entire heavy-duty engine operating range. New variable
geometry turbines and ball-bearing center cartridges allow faster turbocharger spool-up (virtually
eliminating the once-common "turbo lag") while maintaining high flow rates for increased boost
at high engine speeds. Low speed torque output has been dramatically improved for modern
turbocharged engines. However, even with turbocharger improvements, maximum engine
torque at very low engine speed conditions, for example launch from standstill, is increased less
than at mid and high engine speed conditions. The potential to downsize engines may be less on
vehicles with low displacement to vehicle mass ratios, for example, a very small displacement

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
engine in a vehicle with significant curb weight, cargo weight or towing, in order to provide
adequate acceleration from standstill, particularly up grades or at high altitudes.
Use of gasoline direct injection (GDI) systems with turbocharged engines and charge air
cooling also reduces the fuel octane requirements for knock limited combustion and allows the
use of higher compression ratios. Ford's "EcoBoost" downsized, turbocharged GDI engines
introduced on MY 2010 light-duty vehicles allow the replacement of V8 engines with V6
engines with improved 0-60 mph acceleration and with fuel economy improvements of up to 12
percent as documented in their technical paper.12
Recently published data with advanced spray-guided injection systems and more
aggressive engine downsizing targeted towards reduced fuel consumption and CO2 emissions
reductions indicate that the potential for reducing CO2 emissions for turbocharged, downsized
GDI engines may be as much as 15 to 30 percent relative to port-fuel-injected engines.
Confidential manufacturer data suggest an incremental range of fuel consumption and CO2
emission reduction of 4.8 to 7.5 percent for turbocharging and downsizing. Other publicly-
available sources suggest a fuel consumption and CO2 emission reduction of 8 to 13 percent
compared to current-production naturally-aspirated engines without friction reduction or other
fuel economy technologies: a joint technical paper by Bosch and Ricardo suggesting fuel
economy gain of 8 to 10 percent for downsizing from a 5.7 liter port injection V8 to a 3.6 liter
V6 with direct injection using a wall-guided direct injection system;13 a Renault report
suggesting a 11.9 percent NEDC fuel consumption gain for downsizing from a 1.4 liter port
injection in-line 4-cylinder engine to a 1.0 liter in-line 4-cylinder engine, also with wall-guided
direct injection;14 and a Robert Bosch paper suggesting a 13 percent NEDC gain for downsizing
to a turbocharged DI engine, again with wall-guided injection.15 These reported fuel economy
benefits show a wide range depending on the SGDI technology employed and the use of these
technologies are directly applicable to heavy-duty SI engines.
The agencies reviewed estimates from the 2017-2025 final light-duty rule, the TSD, and
existing public literature. The previous estimate from the MYs 2017-2025 suggested a 12 to 14
percent effectiveness improvement, which included low friction lubricant (level one), engine
friction reduction (level one), DCP, DVVL and SGDI, over baseline fixed-valve engines, similar
to the estimate for Ford's EcoBoost engine, which is already in production in light-duty and .
Additionally, the agencies analyzed Ricardo vehicle simulation data and the 2015 NHTSA
Technology Study for various turbocharged engine packages.
2.2.6 Engine Down Speeding
In general, engine down speeding has been determined to reduce frictional losses and also
reduce the need for component temperature protection in SI engines. Component protection
occurs at higher engine speeds and loads where components such as exhaust valves, exhaust
manifolds, catalysts and other components in the exhaust system reach temperatures where
materials may require cooling to prevent damage or reduced durability and accelerated
deterioration. The SI engine has various methods of accomplishing this protection requirement
including using additional fuel enrichment to act as a coolant in the exhaust. Other methods to
reduce exhaust component temperatures include reducing engine output such as torque
governing through variable valve timing, limiting boost in boosted engines or simply reducing

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
air flow into the engine by commanding the electronic throttle to a smaller percentage opening
thereby reducing available air volume.
In the case of chassis certified pick-ups and vans, down speeding is generally achieved by
managing the transmission gear selection in electronically controlled automatic transmissions. It
is largely contained in the transmission technology description in Chapter 2.5 below. There is
typically no incentive to implement additional strategies for limiting engine speed as described
above as they are not quantified in the test cycles and may require a reduction in advertised rated
engine power which can become a competitive disadvantage.
Vocational vehicles which use SI engines certified to GHG and criteria emissions over
the FTP engine dyno cycle can capture the benefits of down speeding more favorably. Since
FTP engine certification is based on a test method that first quantifies the total available engine
power from idle to the electronically governed engine top speed or rev limiter, the opportunity
exists to shift the entire engine operation down to lower engine speeds where frictional losses are
lower and need for temperature protection is reduced. This strategy will generally require the
engine manufacturer to reduce peak power and engine speed rating of the engine. This strategy
has not been used in past SI engine certifications so little information exists about its
effectiveness but the expected range of effectiveness is 0 to 4 percent depending on the
aggressiveness of the down speeding.
2.3 Technology Principles - CI Engines
In this section, technology principles for CI engines will be discussed. Although most
technologies discussed here, with the exception of engine downsizing, down speeding, and WHR
with Rankine cycle technology were considered by the agencies as potentially available for
compliance with the Phase 1 engine standards, the level of improvement and complexity are
different for Phase 2. It should be mentioned that the technologies discussed here are for
compression ignition diesel engines and are not interchangeable with technologies used for spark
ignition engines. See the spark ignition engine discussion in Chapter 2.2 Technology Principles
- SI Engines.
2.3.1 Low Temperature Exhaust Gas Recirculation
Most LHDD, MHDD, and HHDD engines sold in the U.S. market today use cooled EGR,
in which part of the exhaust gas is routed through a cooler (rejecting energy to the engine
coolant) before being returned to the engine intake manifold. EGR is a technology employed to
reduce peak combustion temperatures and thus NOx. Low-temperature EGR uses a larger or
secondary EGR cooler to achieve lower intake charge temperatures, which tend to further reduce
NOx formation. For a given NOx requirement, low-temperature EGR can allow changes such as
more advanced injection timing that would increase engine efficiency slightly more than one
percent. Because low-temperature EGR reduces the engine's exhaust temperature, it has not
been considered as part of a technology package that also includes exhaust energy recovery
systems such as turbocompounding or a bottoming cycle.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.3.2	Combustion System Optimization
Improvements in the fuel injection system allow more flexible fuel injection capability
with higher injection pressure and can improve engine fuel efficiency, while maintaining the
same emission level. Combustion system optimization, featuring piston bowl, injector tip and
the number of holes, in conjunction with the advanced fuel injection system, is able to further
improve engine performance and fuel efficiency. Manufacturers have been working to improve
engines in these areas for some time. At this point, all engine manufacturers have substantial
development efforts underway that we project will be translated into production in the near
future. Some examples include the combustion development programs conducted by
Cummins16, Detroit Diesel17, and Navistar18 funded by Department of Energy as part of the
SuperTruck program. These manufacturers found that improvement due to combustion alone
during this program was 1 to 2 percent. While their findings are still more focused on the
research end of development, specifically targeting one optimal operating point, the results of
these research programs do support the possibility that some of the technologies they are
developing could be applied to production engines in the 2027 time frame. The agencies have
determined that it is feasible that fuel consumption and CO2 emissions could be reduced by as
much as 1.0 percent in the agencies' certification cycles in the 2027 time frame through the use
of these technologies.
Some technologies were evaluated but not included in the agencies' technical feasibility
analysis for the Phase 2 regulation since the agencies do not anticipate these technologies will be
commercially available by 2027. For example, alternative combustion processes such as
homogeneous charge compression ignition (HCCI), premixed charge compression ignition
(PCCI), low-temperature combustion (LTI), and reactivity controlled compression ignition
(RCCI) technologies were not included in the agencies' feasibility analysis for Phase 2. While
these technologies show good indicated thermal efficiency, fuel savings over the entire range of
engine operation is still a major challenge. At the current level of development it is not clear that
the technologies will be in commercial production by 2027. This, however, does not preclude
the use of these technologies for compliance should manufacturers develop and commercialize
these alternative combustion or other approaches.
2.3.3	Model Based Control
Another important area of potential improvement is advanced engine control
incorporating model based calibration to reduce losses of control during transient operation.
Improvements in computing power and speed would make it possible to use much more
sophisticated algorithms that are more predictive than today's controls. Because such controls
are only beneficial during transient operation, they would reduce emissions over the Federal Test
Procedure (FTP) cycle, but not over the Supplemental Emission Test (SET) cycle. Detroit Diesel
introduced the next generation model based control concept, achieving 4 percent thermal
efficiency improvement while simultaneously reducing emissions in transient operations in their
earlier report.19 More recently, this model based control technology was put into their one of
vehicles for final demonstration under DOE's SuperTruck program.20 Their model based
concept features a series of real time optimizers with multiple inputs and multiple outputs. This
controller contains many physical based models for engine and aftertreatment. It produces fully
transient engine performance and emissions predictions in a real-time manner. Although we do

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
not project that this control concept would be in MY 2017 production, real time model control
could be in production during the Phase 2 time frame, thus significantly improving engine fuel
economy.
2.3.4 Turbocharging System
Many advanced turbocharger technologies can be added into production in the time frame
between MYs 2021 and 2027 and some of them are already in production, such as mechanical or
electric turbocompound, more efficiency variable geometry turbine, and Detroit Diesel's
patented asymmetric turbocharger. A turbocompound system extracts energy from the exhaust
to provide additional power. Mechanical turbocompounding includes a power turbine located
downstream of the turbine which in turn is connected to the crankshaft to supply additional
power. On-highway demonstrations of this technology began in the early 1980s. It has been
first used in heavy duty production by Detroit Diesel for their DDI5 and DDI6 engines. That
company claims a 3 to 5 percent fuel consumption reduction due to the system.21 Results are
duty cycle dependent, and require significant time at high load to see a fuel efficiency
improvement. Light load factor vehicles can expect little or no benefit. Volvo reports two to
four percent fuel consumption improvement in line haul applications, which would be likely in
production even before 2020.22
Electric turbo-compound is another potential technology that can improve engine brake
efficiency. Efficiencies are attained through better vehicle integration and lower backpressure
impacts. Since the electric power turbine speed is no longer linked to crankshaft speed, this
allows more efficient operation of the turbine. Navistar reports on the order of a 1 to 1.6 percent
efficiency improvement over mechanical turbocompound systems at 0.5 to 0.7 gm/hp-hr engine-
out NOx levels.23'24 This concept, however, does not work well with lower engine out NOx as
indicated in the report, as zero benefit is reported at 0.3 to 0.4 gm/hp-hr engine-out NOx, due to
lower exhaust gas temperatures. Navistar reports a 1.6 percent fuel efficiency improvement,
again as compared to a mechanical turbocompound system.
Two-stage turbocharger technology has been used in production by Navistar and other
manufacturers. Ford's new developed 6.7L diesel engine features a twin-compressor
turbocharger. Higher boost with wider range of operations and higher efficiency can further
enhance engine performance, thus fuel economy. It is expected that this type of technology will
continue to be improved by better matching with system and developing higher compressor and
turbine efficiency.
Furthermore, improved turbocharger efficiency when combined with turbocompounding
was shown in the SwRI study to reduce fuel consumption while maintaining criteria emissions
limits. Findings show that there is limited scope for improved turbocharger efficiency on
engines which do not use turbocompound, because an increase in turbocharger efficiency would
result in reduced or eliminated EGR flow which in turn would cause the engine to exceed NOx
emissions requirements.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.3.5	Engine Breathing System
Various high efficiency air handling (air and exhaust transport) processes could be
produced for heavy duty applications in the Phase 2 time frame. To maximize the efficiency of
such processes, induction systems may be improved by manufacturing more efficiently designed
flow paths (including those associated with air cleaners, chambers, conduit, mass air flow
sensors and intake manifolds) and by designing such systems for improved thermal control.
Improved turbocharging and air handling systems must include higher efficiency EGR systems
and intercoolers that reduce frictional pressure loss while maximizing the ability to thermally
control induction air and EGR. EGR systems that often rely upon an adverse pressure gradient
(exhaust manifold pressures greater than intake manifold pressures) must be reconsidered and
their adverse pressure gradients minimized. "Hybrid" EGR strategies which rely upon pressure
gradients and EGR pumps may provide pathways for improvement. Other components that offer
opportunities for improved flow efficiency include cylinder heads, ports and exhaust manifolds
to further reduce pumping losses. Cummins reports 1.4 percent through optimization.25 Detroit
Diesel projects a 2 percent fuel efficiency improvement through air handling system
development.26 Navistar predicts almost 4 percent through a combination of variable intake
valve closing timing (IVC), turbocharger efficiency and match improvements. A few plots in
this reference show another 4 percent, but these are not explained.
Variable air breathing systems such as variable valve actuation may provide additional
gains at different loads and speeds. The primary gain in diesel engines is achieved by varying
the EVO event versus engine speed and load, in conjunction with turbocharger optimization to
minimize blowdown losses. Navistar reports a 1.25 percent fuel consumption improvement.23
Again, all these reference points are referred to a single optimal point from the DOE SuperTruck
program.
2.3.6	Engine Parasitic and Friction Reduction
Engine parasitic and friction reduction is another key technical area that can be further
improved in the 2020 to 2027 time frame. Reduced friction in bearings, valve trains, and the
piston-to-liner interface can improve efficiency. Friction reduction opportunities in the engine
valve train and at its roller/tappet interfaces exist for several production engines. The piston at
its skirt/cylinder wall interface, wrist pin and oil ring/cylinder wall interface offers opportunities
for friction reduction. Use of more advanced lubricating oil that will be available in the future
will also play a key role in reducing friction. Any friction reduction must be carefully developed
to avoid issues with durability or performance capability. Lube oil and water pumps as well are
another area where efficiency improvements will occur. Navistar identifies a combined
improvement of up to 2 percent through reduced bearing friction, reduced piston and ring
friction, and unspecified lube oil pump improvements.27 In their 2012 paper they report 5.5
percent improvement through a combination of friction reduction and both lube and cooling
system improvements.23 In this same presentation they specified 0.45 percent demonstrated
through water pump improvements and 0.3 percent through lube pump improvements. The total
number of 5.5 percent remains optimistic, even for a single optimal test point. Cummins reports
a combined number of 3 percent.25. Detroit Diesel reports a combined number of 2 percent, with
0.5 percent coming from improved water pump efficiency. 26 Navistar shows a 0.9 percent
benefit for a variable speed water pump and variable displacement oil pump; 0.5 percent for

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
piston/ring/liner friction reduction; and 0.6 percent for bearing friction reduction23. In addition,
Federal-Mogul recently announced new piston ring coatings that can lead to a 20 percent
reduction in engine friction, and, in looking to the future, sees an opportunity to reduce friction
by an additional 30 percent, which is equivalent to a 1.2 percent reduction in brake specific fuel
consumption at road load conditions.28 It should be noted that water pump improvements
include both pump efficiency improvement and variable speed or on/off controls. Lube pump
improvements are primarily achieved using variable displacement pumps and may also include
efficiency improvement. All of the results shown in this paragraph are demonstrated through
DOE's SuperTruck program under a single optimal operating point, which has not been changed
since the proposal.
In addition, SwRI's reports show that if the exact certification cycles, weighting and
vehicle weights are used, the friction reduction in the Phase 2 timeframe is in the range of 1.47
percent compared to a 2018 baseline engine.7
2.3.7	Integrated Aftertreatment System
All manufacturers now use diesel particulate filters (DPF) to reduce particulate matter
(PM) and SCR to reduce NOx emissions, and these types of technologies are likely to be used
for compliance with criteria pollutant standards for many years to come. There are three areas
considered to improve integrated aftertreament systems, which result in a reduction of fuel
consumption. The first is better combustion system optimization through increased
aftertreatment efficiency. The second is reduced backpressure through further development of
the devices themselves. The third is reduced ammonia slip out of SCR during transient
operation, thus reducing net urea consumption. Navistar reports a 7 to 8 percent improvement in
efficiency projected through a combination of higher cylinder pressure, injection optimization,
and engine/aftertreatment optimization.23 Cummins reports a 0.5 percent improvement through
improved aftertreatment flow (catalyst size optimization and improved NOx surface
utilization)25 Detroit Diesel projects a 2 percent fuel efficiency improvement through reduced
use of EGR, thinner wall DPF, improved SCR cell density, and catalyst material optimization.26
2.3.8	Engine Downsizing and Down Speeding
Engine downsizing can be more effective if it is combined with down speeding which
leads to increased vehicle efficiency through lower power demand. This lower power demand
shifts the vehicle operating points to lower load zones, which moves the engine away from some
of the optimum operation points. In order to compensate for this loss, down speeding allows the
engine to move back into the optimum operating points resulting in reduced fuel consumption.
Increasing power density by reducing the engine size allows the vehicle operating points to move
back to the optimum operating points, thus further improving fuel economy. Both Detroit Diesel
and Volvo demonstrate the same methodology for proper implementation of downsizing 29'30
Detroit Diesel also shows that engine downsizing can result in friction reduction due to a
reduction in engine surface area when compared to a bigger bore engine.26
Engine down speeding can also be an effective fuel efficiency technology even when
used alone (i.e. not in combination with engine downsizing), especially when a vehicle uses a
fast axle ratio. Down speeding, in this situation, can allow the engine to operate in a lower speed

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
zone that is closer to or just in the middle of engine sweet spot, which is typically in the speed
range of 1100-1200 rpm for a heavy duty engine. In order to take advantage of a fast or low axle
ratio, the engine must be optimized toward the low speed zone by either generating higher peak
torque in the lower speed zone or shifting the entire rating speed into a lower rating, or a
combination thereof. The engine air handling and combustion system, as a result of these
changes, must be re-optimized to accommodate a typical higher peak cylinder pressure rise.
Depending on how the engine system is optimized, the overall engine fuel consumption can be
improved. However, from an engine certification standard point, such as the 13-mode SET
cycle, down speeding is always accompanied by moving mode speeds to a lower speed zone,
which usually take advantage of the sweet spot, thus making the engine more efficient in terms
of the certification cycle. On the other hand, from a vehicle operating standard point, the benefit
of down speeding is primarily realized through the use of a lower axle ratio, allowing the engine
to operate in an optimal zone.
2.3.9 Waste Heat Recovery
Organic Rankine Cycle waste heat recovery (WHR) systems have been studied for many
years. The agencies' overall assessment of WHR as a fuel saving technology is that it offers
great promise in the long term. However, it would take several years to develop, and initially, it
would be viable primarily in line-haul applications. The agencies recognize the many challenges
that would need to be overcome, but believe with enough time and development effort, this can
be done. We have received a large number of comments from the both the NPRM and NOD A
that yield two differing opinions. Most vehicle and engine manufacturers, with one exception,
objected to the purportedly aggressive technology penetration rate reflected in the proposed
engine standards. They argued that the WHR systems in the literature and utilized in the DOE
SuperTruck program are still in the research and development stage, and these systems are still a
long way off with respect to reaching production. Their voiced concern is that bringing this
technology to market before it is ready could lead to high warranty costs and reliability issues,
leading to significant down time for vehicles or fleets, possibly even beyond 2027. One engine
manufacturer, however, indicated that WHR systems could be used in a production setting as
early as the MY 2021 to 2027 time frame because their WHR system is approaching the
prototype stage of development, with projected small market penetration starting in 2021.
The basic approach of a WHR system is to use engine exhaust waste heat from multiple
sources to evaporate a working fluid in a heat exchanger. This evaporated fluid is then passed
through a turbine or equivalent expander to create mechanical or electrical power. The working
fluid is then condensed back to the fluid in the fluid reservoir tank and returned back to the flow
circuit via a pump to restart the cycle. With support of the Department of Energy, three major
engine and vehicle manufacturers have developed WHR systems under the SuperTruck program.
Cummins' WHR system is based on an organic Rankine cycle using refrigerant as the working
fluid.31'32 Their system recovers heat from the EGR cooler, as well as from the exhaust gas
downstream of the aftertreatment system. It converts that heat to power through a mechanical
gear train coupled to the engine's output shaft. Some iterations of their system also sought gains
from low-temperature coolant and lubricant heat rejection via a parallel loop. The system
includes a recuperator that transfers post-turbine energy back into the working fluid loop prior to
the condenser. This recuperator reduces condenser heat rejection requirements and improves
overall system efficiency. Volvo has developed a similar system to Cummins' with variations in

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
terms of hardware components, including the use of ethanol as the working fluid instead of a
refrigerant.33 Daimler, on the other hand, has developed a different type of ethanol based system
to recover heat from the exhaust gas using an electrical generator to provide power to charge a
high-voltage battery that is primarily used to drive a hybrid system.
Pre-prototype WHR systems have been shown to be very efficient under optimized
conditions. In demonstrations where operation occurred at a single optimal engine operating
point, Cummins reported potential efficiency gains from WHR on the order of 2.8 percent from
the baseline engine without WHR31, Volvo reported around 2.5 percent33, and Daimler reported
2.3 percent.29 It is important to note that all of these WHR systems are still in the pre-prototype
stage of research and development. Despite the promising performance of pre-prototype WHR
systems, the cost and complexity of these packages from Cummins, Volvo and Daimler remain
high. The agencies believe that manufacturers will continue to make improvements to these
systems over time, just as they have for other advanced technologies that initially had high cost
and complexity at a comparable stage of development.
WHR technology also poses issues with respect to package size and transient response.
The agencies believe that WHR will be less effective in urban traffic and will most likely be
applied to line haul vehicles. Our projected technology paths for compliance, and projected
technology penetration rates, reflect this assumption.
WHR may offer the benefit of replacing the EGR cooler and decrease cooling system
heat rejection requirements by converting some heat into work. To the extent that WHR systems
use exhaust heat, they may increase the overall cooling system heat rejection requirement, thus
increasing radiator size, which can have a negative impact on cooling fan power needs, as well as
on vehicle aerodynamics. Significant challenges could arise if the space under a vehicle's hood
happens to be tight, leaving little or no room for a larger radiator, thus necessitating a redesign of
the vehicle's front face, sacrificing potential aerodynamic improvements. This issue becomes
more challenging for truck cooling systems that are currently at cooling capacity design limits.
Current WHR systems are heavy, estimated to be on the order of 300-500 lbs depending
on system design. Without time to optimize designs, any attempt to reduce weight by simply
reducing the size of the key components, such as boilers and condensers, would likely have an
adverse impact on the system efficiency. Given enough lead time, the agencies believe
manufacturers might be able to improve materials and designs to reduce overall system weight
without compromising efficiency.
Manufacturers have not yet arrived at a consensus on which working fluid(s) will be used
in WHR systems to balance concerns regarding performance, global warming potential (GWP),
and safety. Current working fluids have a high GWP (conventional refrigerant), are expensive
(low GWP refrigerant), are hazardous (ammonia, etc.), are flammable (ethanol/methanol), or can
freeze (water). One of the challenges is determining how to seal the working fluid properly
under vacuum conditions with high temperature to avoid safety issues for flammable/hazardous
working fluids. Addressing leaks would also be an important issue with respect to greenhouse
gas emission for a high GWP working fluid. Because of these challenges, choice of working
fluid will be an important factor for system safety, efficiency, and overall production viability.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Other key challenges facing WHR systems are their reliability, durability, and market
acceptance. Durability concerns that have been raised include: boiler fouling and cracking
associated with high thermal gradients, thermal shock, condenser fouling, as well as sensor and
actuator durability under harsh temperature and pressure conditions. It can be reasonably
estimated that the current WHR systems under development by major engine manufacturers
consist of at least two hundred parts including expanders, boilers, condensers, and fluid pumps,
together with many fasteners, wiring cables, sensors, actuators, and piping. Determining overall
system efficacy and reliability involves rigorous testing in support of comprehensive Failure
Modes and Effects Analysis (FEMA). These parts, as well as the entire WHR system as a whole,
must undergo severe winter and summer tests. Multiple trucks equipped with the same WHR
system must be run on the road, accumulating millions of miles. During these tests, all failures
must be recorded, associated with specific failure modes or error codes, and the root cause of the
failure must be determined. Warranty costs for each failure mode based on component cost and
labor must be assigned. Due to the large number of components, some of the failure modes
might not be identified during the road tests even with multiple occurrences. It would be a high
risk for any manufacturer to put their new technology into the market without careful system
validation via on-the-road tests. Similarly, owners and operators might be unlikely to risk early
adoption of such a complex technology if premature deployment leads to potential down time,
along with its associated cost.
Based on the literature and preceding discussion, WHR technology can be characterized
as being in the technology demonstration stage for purposes such as the DOE SuperTruck
program. It should be clear that the demonstration defined by DOE SuperTruck program means
that the demonstrated truck with the technologies developed under the DOE program can be
successfully run through a pre-specific routes, and it doesn't mean that technologies used in the
truck reach any matured stage or prototype stage, regardless of cost. Although a few trucks with
WHR technology have been tested on the road,33'34'35 many of the components used in the trucks
and product-acceptable packaging are still years away from production. Figure 2-1 shows a
generic form of the product process flow. As can be seen from this figure, it could take 5-15
years from the applied research/development stage to arrive at the prototype stage depending on
the complexity of the technology. WHR is now in that prototype stage. During the prototype
stage, all prototype components must be available and extensive engine and vehicle tests with
WHR must be conducted. The production start-up phase would follow. After that, significant
efforts must be made to advance the system from a prototype to a commercial product, which
typically takes about five years for complex systems like WHR. During this approximate five-
year period, multiple vehicles will go through weather condition tests, long lead-time parts and
tools will be identified, and market launch and initial results on operating stability will be
completed. Production designs will be released, all product components should be made
available, production parts on customer fleets and weather road testing will be verified before
finally launching production, and distribution of parts to the vehicle service network for
maintenance and repair will be readied.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
5-15years
3-5years

Prototype component available
Testing complete engine/vehicle
Market
requirements
Product Launch
Verified with production parts
on customer fleets and all
weather road testing
Release long-lead p!xte ahd tool
Complete Market launctvronfc^pt
Initial results on operating st^bilrt'
Technical pro<|ucfvpncept
Fuel economy Mtjmafc^d
Technical risks addressedN
Design Released into production
All product components available
Financial feasibility
Simulation and Testing
Applied R/D
Prototype
Production
Figure 2-1 Product Process Flow
The GHG standards themselves can provide an effective incentive for manufacturers to
reach the commercial product stage earlier than would otherwise occur. They can motivate
manufacturers to shorten the period for advancing from a complicated prototype system to a
commercial product and can also help to ensure market penetration after launching a product.
Nevertheless, in order for WHR to be produced commercially, several things are needed. First, it
is critical to optimize the WHR package volume, cooling capability, and aero drag at typical
cruise speeds on highway since the most significant benefits of WHR technology would be in
line-haul applications. Removal of the exhaust heat exchangers located in the exhaust system
would reduce the total system volume and weight. Working fluids need to be selected with a
reasonably low GWP and high performance potential. In addition, the engine with a WHR
system needs to be continuously tested in a very well equipped engine dynamometer. This allows
to continue optimization in a system level as well as identification of issues associated with
reliability. On top of that, the component bench tests, such as individual components like heat
exchangers, condenser, and expander need to be extensively conducted through a series of
durability and performance test protocols for accumulated thousands of hours, thus identifying
any potential issues associated with reliability. In the meantime, one of the most effective
approaches should be to put a few hundred trucks into fleets for trial in the next several years, so
that a comprehensive FEMA can be thoroughly identified and warranty cost analyses be more
precisely conducted before launching into full volume production. The fleet testing results can
also provide valuable feedback to the engine dynamometer tests, thus continuing optimization of
the component size, weight and performance including working fluid. Manufacturers have
shown in the past that a robust FEMA process can address most problems before a technology is
more widely introduced. Therefore, the lead time appears to be one of the most noticeable
constraints.
We believe that all the issues and hurdles discussed above can be resolved with adequate
lead time. However, it would be challenging to predict high rates of initial market penetration
because of the many uncertainties as stated above. The NACFE report 36analyzes a wide range
of HD fuel efficiency technology adoption rates versus time, and we considered these recent
historic trends as we developed our market adoption rate projections. While more mature

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
technologies such as electronic fuel injection and turbocharging are not presented in this report,
the trends for a number of emerging fuel efficiency technologies are depicted. We note that a
number of charts which are relevant here are presented at the end of this report. Many of these
technologies are those that we are projecting to continue to increase in market adoption during
the Phase 2 timeframe. While there are a number of exceptions, many of the technology
adoption rate curves follow an S-shape: slow initial adoption as shown in Figure 2 of this
report36, then more rapid adoption, and then a leveling off as the market saturates (not always at
100 percent).
This characteristic S-curve is further annotated and expanded in the figure below. There
are two curves in this figure. "Simple" typically means that the technology can be relatively
quickly adopted by the market because of the technology complexity. The example includes the
use of aero fairings on the vehicle side, and turbocharger and fuel injection technologies on the
engine side. "Complex" means that the technology is so complicated that the market will take a
much longer time to adopt. WHR with the Rankine cycle is one of these types (but certainly not
the sole example). The agencies thus view it legitimate to apply this type of S-curve to WHR.
This figure also shows the four typical steps to reach high market penetration, but either
technology needs to go through an S-shape curve because of factors indicated on the left side of
this figure, which would make it difficult to quickly bring the technology into the market with
high market penetration. Taking "fleet consideration" of this figure as an example, the payback
time would be the most sensitive. Reliability, down time, limited credible data, resale values, and
capital investment are many of the other concerns. We believe that WHR adoption behavior can
very well follow the S-shape curve, where we project a steeper rise in market adoption in and
around the 2027 timeframe. We have worked closely with one of the engine manufacturers who
are leading WHR development. With reliable and credible CBI information, we now believe that
our initial estimate for 15 percent market penetration of WHR in MY 2027 was conservative.
Given our averaging, banking and trading program flexibilities and that manufacturers may
choose from a range of other technologies, we believe that manufacturers will be able to meet the
2027 standards, which we based on 25 percent WHR adoption in heavy duty tractor
engines. Again, this illustration is consistent with the findings reported by NACFE.36 For
example, the tire pressure inflation used for trailers follows this type of S-curve took four years
from 1 percent market penetration to 16 percent, and then to 31 percent in another year. One of
the key lessons learned from this report is that if a technology is pushed too hard and too quickly,
the market penetration could be rolled back because of reliability and warranty issues. See 80 FR
40236 noting similar concerns in a general context. Taking idle reduction with diesel APU
engine technology as an example, it quickly reached 15 percent market penetration from 3
percent in one year, and then reached 32 percent in four years, but it quickly dropped back to 13
percent in 3-4 years. This type of behavior could happen to WHR with Rankine cycle
technology if pushed too hard.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
100
sp
c
o
"+ฆ>
Q.
o
T5
<
Fleet Considerations:
Payback
Reliability/down time concerns
Limited credible data
Resale values
Capital investment and credit
Few early adopters
"Show me" mentality
4. Maximums often less
than 100% due to less than
universal applicability of a
particular technology at
full effectiveness
OEM Considerations:
•	Emissions standards
•	Return of investment
•	Warranty costs
3. Rapid increase in market
adoption once
technology is "proven"
2. Initial increases are modest, "follow-
the-leader"
1. Earliest market penetration from test fleets, on a trial basis
Time
"Simple"
	"Complex"
Figure 2-2 S-shape Market Penetration
2.4 Technology Principles - Class 4 to 8 Vehicles
2.4.1 Aerodynamics
The aerodynamic efficiency of heavy-duty vehicles has gained increasing interest in
recent years as fuel prices, competitive freight markets, and overall environmental awareness has
focused owners and operators on getting as much useful work out of every gallon of diesel fuel
as possible. Up to 25 percent of the fuel consumed by a line-haul tractor traveling at highway
speeds is used to overcome aerodynamic drag forces, making aerodynamic drag a significant
contributor to a Class 7 or 8 tractor's GHG emissions and fuel consumption.37 Because
aerodynamic drag varies by the square of the vehicle speed, small changes in the tractor
aerodynamics can have significant impacts on GHG emissions and fuel efficiency of that vehicle.
With much of their driving at highway speed, the benefits of reduced aerodynamic drag for Class
7 or 8 tractors can be significant.38
The common measure of aerodynamic efficiency is the coefficient of drag (Cd) or drag
area (CdA). The aerodynamic drag force (i.e., the force the vehicle must overcome due to air) is
a function of Cd, the area presented to the wind (i.e., the projected area perpendicular to the
direction of travel or frontal area), and the square of the vehicle speed. Cd values for today's
line-haul fleet typically range from greater than 0.80 for a classic body tractor to approximately
0.58 for tractors that incorporate a full package of widely, commercially available aerodynamic
features on both the tractor and trailer.
While designers of heavy-duty vehicles and aftermarket products try to aerodynamically
streamline heavy-duty vehicles, there are some challenges. Aerodynamic design must meet
practical and safety needs such as providing for physical access and visual inspections of vehicle
equipment. Since weight added to the vehicle can impact its overall fuel efficiency, GHG
emissions and, in limited cases, the amount of freight the vehicle can carry, aerodynamic design

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
and devices must balance the aerodynamic benefit with the contribution to the vehicle weight. In
addition, aerodynamic designs and devices must balance being as light and streamlined as
possible with in-use application durability to withstand the rigors a working freight vehicle
encounters while traveling or loading and unloading.
However, there are some macro and micro scale techniques that can be employed to
reduce vehicle drag such as reducing vehicle size, especially, the frontal area; smoothing the
shape to make it more aerodynamically efficient, thus reducing the Cd; and/or re-directing air to
prevent entry into areas of high drag (e.g., wheel wells) or to maintain smooth air flow in certain
areas of the vehicle. Reducing the size of the vehicle can reduce the frontal area; which reduces
the pressure building up on the lateral surface area exposed to the airflow. Improving the vehicle
shape may include revising the fore components of the vehicle such as rearward canting/raking
or smoothing/rounding the edges of the front end components (e.g., bumper, headlights,
windshield, hood, cab, mirrors) or integrating the components at key interfaces (e.g.,
windshield/glass to sheet metal) to alleviate fore vehicle drag. Finally, redirecting the air to
prevent areas of low pressure and slow moving air; thus eliminating areas where air builds
creating turbulent vortices and increasing drag. Techniques such as blocking gaps in the sheet
metal, ducting of components, shaping or extending sheet metal to reduce flow separation and
turbulence are methods being considered to direct air from areas of high drag (e.g., underbody,
tractor-trailer gap, underbody and/or rear of trailer).
The issue for heavy-duty vehicles is that the cab and/or passenger compartment is
designed for a specific purpose such as accommodating an inline cylinder engine or allowing for
clear visibility given the size of the vehicle. Consequently, a reduction in vehicle size and/or
frontal area may not be realistic for some applications. This also may necessitate an expensive,
ground-up vehicle redesign and, with a tractor model lifecycle of up to 20 years, may mean that a
mid-cycle tractor design is not feasible. In addition, the frontal area is defined by the shape
behind the cab so reducing just the cab frontal area/size reduction may not be effective. Thus,
this approach is something that may occur in a long-term timeframe of 10-20 years from today.
Instead, most heavy-duty tractor manufacturers have explored, or are exploring, the latter
two techniques in the short-term. Compared to previous generation tractors, every high roof
tractor today has a roof fairing directing air over the top of the cab, fuel tank/chassis fairings that
prevent side air from flowing underneath the vehicle, and cab side extenders that prevent flow
from being trapped in the tractor-trailer gap. As a compliance strategy for HD Phase 1, many
manufacturers refined the aerodynamic shape of their front end components and other
components (e.g., curving or further extending side extenders) resulting in efficiency difference
between pre- and post-HD Phase 1, model year tractor aerodynamic performance. Further,
manufacturers have developed new tractor designs that are taking advantage of sealing gaps in
sheet metal to redirect the flow and introducing some hard edges to induce turbulent flow on
certain surfaces to prevent premature flow separation and downstream turbulent flow. For HD
Phase 2, we anticipate manufacturers would continue to apply these techniques across their
models and continue to explore refinements and re-designs in other areas of the tractor.
In addition to tractor improvements, there has been growth in the market for trailer
aerodynamic devices encouraged by our successful SmartWay Partnership and Technology
Verification Program. These devices function similar to components on the tractor by preventing

-------
*** E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review ***
air intrusion into areas of the trailer prone to high aerodynamic drag including the tractor-trailer
gap, the trailer underhody, and the rear of the trailer as shown in Figure 2-3 and Figure 2-4
below.
520
480
440
400
360
320
I 260
0
1	240
Q
200
160
120
80
40
0


	1	1	1	
Bas e 1 i ne-N o-Anerno mete r
	



	



































Slight drag increase along entire vehicle














IT




































































I ฃ


OOi
	1	

Q(
sr i
12 14 16 18
X location fml
Figure 2-3 Progression of Total Drag along a Typical Line-Haul Tractor-Trailer Vehicle
Figure 2-4 Low Pressure Regions Contributing To Aerodynamic Drag Along A Typical Line-Haul Tractor-
Trailer Vehicle
To address this, trailer front/nose devices are being used to round the front end and edges
of the trailer while also reducing the tractor-trailer gap; skirts on the side of the trailer prevent air
entering the underside of the trailer and becoming turbulent on the various underbody structure
components; and trailer aft/rear treatments reduce separation of air flow of the rear edge of the
trailer to reduce the large wake of turbulent air behind the trailer. Based on current SmartWay
Technology Verification, these devices can reduce fuel consumption from 1 to 9 percent,
depending on the technology, and if it is employed indi vidually or in combination.
As a result, we believe there is an opportunity within FID Phase 2 to promote continual
improvement of tractor aerodynamics and capitalize on the potential improvement that
aerodynamic trailer devices can provide for trailers, and for overall combination tractor-trailer
efficiency.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
2.4.2 Advanced Aerodynamic Concepts
The ITD Phase 2 standards will be fully phased in by the 2027 model year. This
represents a significant amount of time from today's action. As such, it is possible that by the
time the Phase 2 standards are implemented, the state of heavy-duty aerodynamic technology and
performance may have advanced significantly. Thus, there may be a need to have standards to
adequately address future tractor-trailer aerodynamic advances.
Accordingly, we are considering aerodynamic concepts that can achieve aerodynamic
performance beyond that of the aerodynamic-attributed improvements in the ITD Phase 2
standards. There are many approaches applicable to today's tractors and trailers that are not
considered in the HD Phase 2 standards and there is also ongoing advanced research aimed at
creating a completely new design paradigm for tractor-trailer combinations.
The advanced aerodynamic standards would not be required but would rather serve as a
marker for future aerodynamic concepts and/or as a metric for HD Phase 2 advanced/innovative
aerodynamic technologies.
2.4.2.1 Aerodynamic Improvements to Current Tractor-Trailer Combinations
Based on Existing Technology
2.4.2.1.1 Manufacturer Commercial Initiatives
In order to anticipate technology advancement, it is important to benchmark current
technology improvements based on today's tractors and trailers. A number of Class 8 tractor
OEM's have incorporated the technologies requested by their customers to improve fuel
economy and to meet the HD Phase 1 standards. These technologies include side skirts, boat
tails and roof fairings as well as some driver monitoring tools. Recently, Jack Roberts released
an article on the internet titled: "Photo, video: Western Star introduces re-designed on-highway
tractor." 39
Figure 2-5 Pictures of the Western Star Class 8 Tractors
In addition to providing photos and videos of Western Star's redesigned on-highway
tractor, the article describes a multitude of new features that define the new tractor. These
features include:

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
•	A new sweptback four piece bumper with an under bumper valance that contributes
to aerodynamic efficiency.
•	New halogen headlights that are optimized for aerodynamic performance and
excellent visibility.
•	A state-of-the-art visor specifically engineered to work with the impressive slope in
the hood's rear air ramp to direct airflow over the cab without an aerodynamic
penalty.
•	Roof and cab fairings that sweep back for tighter trailer gap and help direct air flow
over and around the trailer.
•	Optional chassis side fairings that reduce drag by up to 6 percent while still providing
easy access to batteries and DEF tank.
•	The Western Star Twin Force dual air intake, which feeds a massive centrally
mounted air filter to improve efficiency.
This example demonstrates that manufacturers are continuing to find ways to improve
tractors and are continually exploring concepts, such as those in used in the SuperTruck
initiative, to improve commercially-available products.
2.4.2.1.2 Supplier Research: SABIC Roof Fairing Technology and
Manufacturing
Developments in aerodynamics have long been assumed to yield advances in vehicle fuel
efficiency. SABIC Innovative Plastics US LLC (SABIC) evaluated a variety of injection
moldable thermoplastic roof fairing designs for a heavy tractor day cab to quantify efficiencies
that could be obtained through advanced aerodynamics. Computational Fluid Dynamic (CFD)
modeling was performed by Exa Corporation, an industry recognized leader in CFD. Multiple
designs exhibited significant reductions in drag compared to a baseline roof fairing (Figure 1 of
Figure 2-6). The baseline represented a top performing roof fairing on the market today. The
best performing SABIC concept (Figure 2-7) achieved a 5.8 percent reduction in drag and fuel
use compared to the baseline. Under the well-established 2:1 relationship between delta drag
and fuel use, the fuel efficiency improved by nearly 3 percent from the baseline design.
The design concept optimized the shape to manage the airflow over the vehicle and
enable reduced drag and increased fuel economy. Air channels - developed for injection
molding processes - limit the air stagnation on the front of the trailer as well as accelerate and
control the direction of the air flow. This innovative concept has been validated using state of
the art CFD methods. On vehicle tests are suggested to validate findings from these studies,
(from Matthew D. Marks, Senior Business Manager, Regulatory Automotive and Mass
Transportation, November 14, 2014).

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Figure 1: baseline roof fairing	Figure 2: SABIC concept roof fairing
Surface X-Force [dimless]
-0.300	-0150	O.OQO	0.150	0.300
Figure 2-6 Surface X-Force (dimensionless) on Baseline and SABIC Concept Roof Fairing
Aerodynamic (surface) force is the force exerted on a body whenever there is a relative
velocity between the body and the air. These plots represent this force in the direction of the
vehicle travel at highway speeds. Red indicates a 'pushing' of the vehicle rearward, while blue
indicates a 'pulling' of the vehicle forward.
Figure 3: SABIC concept roof Figure 4: SABIC concept roof
fairing showing directed airflow	fairing showing airflow detail
Figure 2-7 SABIC Concept Roof Fairing Operation
2.4.2.1.3 HD Phase 1 Research: External Active Grille Shutter Potential on
Heavy-Duty Tractors
During ITD Phase 1 aerodynamic assessment, we looked at several trends to understand
some of the aerodynamic trends such as removal of tractor chassis fairings and side extenders,
different tractor-trailer gap widths, and different trailer leading edge radii. However, one trend
of particular relevance to advanced aerodynamic improvements for current tractors is the case of
open versus closed grille.
We evaluated the open vs. closed grille trend in the full and reduced scale wind tunnel.
Below in Figure 2-8 is a picture of a 1/8'1' scale tractor model in the reduced scale wind tunnel
with the grille covered with aluminum tape to simulate a fully closed grille.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Figure 2-8 Photo of l/8th Scale Model of a Tractor with the Front, External Grille
Covered With Aluminum Tape to Simulate A Closed Grill Configuration
Below in Table 2-1 and Table 2-2 are the results of our open versus closed grille evaluations in
the full and reduced scale wind tunnel separately. The tables provide the deltas for an open grille
CdA minus the closed grille C\iA; where the CdAs have been corrected for blockage, in the case
of the full scale wind tunnel, and normalized for differences in measured frontal area between the
full and reduced scale wind tunnels using a nominal frontal area of 10.4 m2 (111.95 in2). For the
full scale wind tunnel, only one tractor OEM was tested. In contrast, for the reduced scale wind
tunnel, three tractor OEMs were tested.
Table 2-1 Full Scale Wind Tunnel Results for Open verses Close Grille Configurations
TRACTOR
MODEL
DELTA WACdA
r?55MPH
% DELTA CdA VS. OPEN GRILLE
CdA
1
0.03
0.60%
Table 2-2 Reduced Scale Wind Tunnel Results for Open versus Close Grille Configurations
TRACTOR
MODEL
DELTA WACdA
SiSMPH
% DELTA CdA VS. OPEN GRILLE
CdA
A
0.10
1.69%
B
0.12
1.89%
C
0.09
1.45%
Based on the data in these tables, there is a potential wind-average drag improvement of
0.6 percent to 1.45 percent from closing off the external, front grille of the tractor. This indicates
the potential of active grille shutter systems on heavy-duty tractors. These systems are currently
being applied on light duty vehicles behind the external grille to improve aerodynamics.
However, a recent SAE paper determined that the optimal position for active grille shutter
systems was the external grille flush with the vehicle sheet metal.40 This technique could be
implemented on the external grille designs for current-design, heavy-duty tractors as well.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.4.2.1.4 National Research Council of Canada Historical Research on
Improving Heavy-Duty Tractors
The National Research Council of Canada (NRC-Can) performed an assessment of the
drag effect of various tractor components41 and found the following in Table 2-3.
Table 2-3 Reduced Scale Wind Tunnel Results for Open versus Close Grille Configurations
COMPONENT
DELTA
WACdA
OEM Side Mirrors
-0.156
OEM Fender Mirrors
-0.098
Wheel Covers (Tractor and Trailer)
0.020
Tractor Drive Axle Wrap-Around Splash Guards
0.049
Roof Fairing Rear-Edge Filler
0.137
Based on this table, there is the potential to improve tractor aerodynamics by 0.206
WACdA) with the addition of wheel covers, drive axle wrap around splash guards, and roof
fairing rear edge filler, and up to 0.460 if the OEM side and fender mirrors are replaced with a
camera system, as suggested by the study, and combined with the wheel covers, drive axle wrap
around splash guards, and roof fairing rear edge filler. Therefore, considering the current wind-
average drag performance of current heavy-duty tractors, this study demonstrates the possibility
to improve tractors an additional ~1 percent with some simple changes.
2.4.2.2 Aerodynamic Improvements to Current Tractor-Trailer Combinations
Based on Complete Vehicle Redesign
This section contains summaries of ongoing work from various DOE efforts as well as
individual efforts such as Airflow Truck Company to develop improved aerodynamic Class 8
vehicles. In addition to aerodynamics, there are other technologies such as driver awareness and
ability to drive for maximum fuel economy with increased aerodynamics. Overall it is expected
that the research being performed over the next year or two will reveal drastic improvements in
CdA and fuel economy. DOE's Lawrence Livermore National Laboratory is also looking at the
aerodynamics of tankers.
2.4.2.2.1 Collaborative, Government-Industry Advanced Aerodynamic
Research: SuperTruck Program
DOE's SuperTruck project is one of several initiatives which is a public-private initiative
to stimulate innovation in the trucking industry through sponsorship from government agencies,
companies, national laboratories and universities. DOE's Vehicle Technologies Program
provided matching funds to the program. Four programs basically involved all major vehicle
and engine manufacturers were awarded by DOE under SuperTruck program. They are
Cummins, Daimler, Navistar, and Volvo. Cummins was teamed up with Peterbilt on the vehicle
side of the program.
The goal of the SuperTruck Initiative was to achieve 50 percent freight efficiency
improvement with 30 percent from vehicle and 20 percent from engine compared to a 2009

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
vehicle. This means that it require development of a tractor that could meet or exceed 10 mpg -
where tractors at this point are averaging between 5.5 and 6.5 mpg. Advances in engines,
aerodynamics and more helped the tractor project increase its fuel economy. The SuperTruck
objectives included development and demonstration of a highly efficient and clean diesel engine,
an advanced waste heat recovery system, an aerodynamic tractor and trailer combination and a
lithium ion battery auxiliary power unit, to reduce engine idling.
Significant progress has been made since the initiation of this program in 2010. Two programs
are particularly worth noting. They are the Cummins-Peterbilt and Daimler programs. The
Cummins-Peterbilt SuperTruck project team was the first to report and demonstrate a
SuperTruck vehicle withl0.7mpg. Details of the SuperTruck are given in four videos on the
todaystrucking.com website.42 Aerodynamic features of the tractor include the following:
airflow into the engine compartment (through the front bumper, through the radiator and under
the vehicle), less clearance between the road and the bottom of the tractor (rubber skirt under
steps), close gaps on tractor/trailer (between hood and bumper, etc.), minimized gap between the
trailer and tractor with a ball and socket design, full trailer skirt, roof fairing, smaller mirrors,
minimized gap between wheels and wheel wells, wheel covers, boat tail, air foil on rear bumper
design, single wide tires, and perforated mud flaps that allow air to bypass through them and
reduce drag. A picture of this truck based on a Peterbilt tractor is shown in Figure 2-9 below.
Eaton Corp, also part of the Cummins-Peterbilt SuperTruck project team, contributed
technologies including the design, development and prototyping of an advanced automated
transmission that facilitated reduced engine-operating speeds. Cummins and Eaton jointly
designed shift schedules and other features to yield further improved fuel efficiency.
Even with the additi on of these aerodynamic features, overall the tractor mass was
reduced by over 1,300 lbs. The article states that the CFD analysis of the tractor showed a 50
percent reduction in drag and with a 2:1 drag reduction the aero improvements resulted in a 25
percent improvement in fuel economy. In the 300 mile test course shown on the video, it was
stated that the tractor achieved 10.7-11.1 mpg.
	
)>
~T 1 hm

su

• I <

Figure 2-9 Peterbilt SuperTruck Concept (Picture from: http://www.peterbilt.com/about/media/2014/396/)
This effort represents the first step in the evolution of improving the aerodynamic
efficiency of tractor-trailer by radically redesigning today's tractor-trailer combination, as a
wholly integrated system rather each component, tractor and trailer, independently.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Just one year later after Cummins' demonstration, Daimler demonstrated their own
SuperTruck vehicle with 12.2 mpg as showed in Figure 2-10.
Figure 2-10 Daimler SuperTruck Vehicle (picture from: http://freightlinersupertmck.eom/#main)
The key enabling technology on the aero side in this vehicle includes, but is not limited to, full
tractor aero with cab/sleeper, underbody, drive wheel fairing, mirror cam, steer wheel, and full
side extender. In addition, this vehicle also includes a 50 percent BTE DDI 1 Engine with WHR,
predictive hybrid controller, predictive engine controller, new final drive active oil management
with high efficiency gear oil, lightweight aluminum frame and cross members, ultra-light weight
air suspension, advanced load shift with 6x2 axle, solar reflective paint, and enhanced Trailer
aerodynamics. More detailed features on this Daimler truck can be seen in their DOE report34.
2.4.2.2.2 Government Sponsored Advanced Aerodynamic Research: Lawrence
Livermore National Laboratory
Lawrence Livermore National Laboratory's (LLNL) Kambiz Salari presented
information at the 2014 DOE Annual Merit Review on "DOE's Effort to Improve Heavy Duty
Vehicle Fuel Efficiency through Improved Aerodynamics." A joint project with Wabash,
Navistar, Michelin, Safeway, Frito Lay, Praxair, Freight Wing Inc., ATDynamics, Kentucky
Trailer and Spirit was funded in 2013 and 2014. The objective was to develop a new integrated
tractor-trailer design from ground up by first, designing the first generation of an integrated
tractor-trailer geometry called Generic Speed Form one (GSF1) and second, performing wind
tunnel tests of selected aero devices for tractor-trailers and tankers to improve fuel efficiency.
The goal was to reduce aerodynamic drag of Class 8 tractor-trailers by approximately 25 percent
leading to a 10-15 percent increase in fuel efficiency at 65 mph. In addition, the group
developed an aerodynamic tractor-trailer prototype designed to achieve 50 percent reduced
aerodynamic drag as shown in Figure 2-11. This effort represents the next generation of tractors
and trailers: a completely redesigned, fully integrated, optimized shape for the tractor-trailer
combination.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Tractor-trailer integration is the next step in
achieving a radical improvement in fuel economy
> 50% aerodynamic drag
reduction compared to
heavy vehicles on the
road today
Lawrence Uvwmwe National LabcrHay
Figure 2-11 Pictures Showing Future Heavy-Duty Tractor Trailer Concept to Achieve >50 percent
Aerodynamic Improvement for Class 8 Line Haul Heavy-Duty Vehicles
2.4.2.2.3 Independent Advanced Aerodynamic Research: Airflow Truck
Company Bullet Truck Concept
In addition to the work being performed by the OEMs and consortiums mentioned above,
there are also independent commercial initiatives underway to radically redesign the tractor-
trailer combination similar to the concept by Lawrence Livermore National Laboratories
discussed above.
The Class 8 tractor and trailer modifications in Figure 2-12 were designed, built, and
tested in 2012 by Mr. Robert Sliwa of the Airflow Truck Company. Mr. Sliwa built his first
aerodynamic tractor in the 1983 when he was an owner-operator. After that, Mr. Sliwa became
interested in computers and used his computer background along with his truck driver and race
car driver experience to create the Bullet Truck. His current design is described at
www.airflowtruck.com and his tractor design modifications are similar in appearance to the
bullet looking trains used in Europe. The tractor uses a 1999 engine and the test was conducted
in a manner in which the tractor was driven at 55 mph by an experienced driver throughout its
test while loaded at 65,000 lbs from Newington, Connecticut to Tracy, California.
The website shows that the vehicle achieved 13.4 mpg during this trip that included
traveling through the Rocky Mountains. CFD analyses of the design after the vehicle was built
found a modest decrease in CdA, thus giving credence to the design work under the hood (most
of which are outlined at airflowtruck.com) and driving techniques. Several new technologies
were developed during this work which included retractable tractor steps, all electric air
conditioning, crankshaft mounted cooling fan, computer-controlled fan hub, waterless engine
coolant, reduced engine parasitic losses, full tractor and trailer side skirts, 4 axle ATIS, and an
engine feedback information display.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Figure 2-12 Figure of the Bullet Truck by Airflow Truck Company9
AirFlow has designed and is currently building the third prototype (Proof of Concept) of
a "Hyper Fuel Mileage, Ultra Low GHG Emissions, and readable Class 8 heavy duty truck"
called the StarShip. The StarShip is a Class 8 heavy duty truck tractor that will be mated with a
new 2016 Strick 53' dry van trailer, which is typical of an over-the-road freight hauling trailer.
AirFlow has further modified the stock trailer to be much more aerodynamic than when it left the
Strick factory. There is also a full array of solar panels on the trailer roof. This solar array will
charge batteries mounted on the tractor during the day to enable to provide electric Fleat,
Ventilation, and Air Conditioning (HVAC) to the cab for driver comfort while traveling down
the roadway, and when the driver is engaged in federally mandated rest and safety breaks.
Utilizing a proprietary all-electric FIVAC system will allow the StarShip to reduce GFIG
emissions and increase fuel efficiency by completely removing the diesel engine-driven air
conditioning compressor, and its associated engine parasitic efficiency losses. It will also allow
the StarShip to automatically and periodically turn off its diesel engine belt-driven 300 amp
alternator, further saving fuel and further reducing GHG emissions. These aerodynamic, solar,
and hybridized component improvements will further reduce GHG vehicle emissions and vastly
increase fuel efficiency.
The latest proof of concept vehicle, the StarShip, is due to be completed in Q3 2016 and
will begin its local and regional road testing then. The design of the StarShip continues to be
refined. The StarShip utilizes an experimental 2017 EPA low-emissions certified, six cylinder,
400 horsepower diesel-fueled Cummins engine to power the vehicle. The engine is certified to
produce air pollutants and GHG emissions in an amount significantly below the current 2013
standard. Future versions of the StarShip model may include a hybrid (diesel engine/electric
motor) and/or a purely electric propulsion unit, powered only with an onboard battery bank,
similar to a Tesla automobile.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
iductng fo Airflow iecirSKฎ, iHป wwcf'i moir innovolbv nuck In '!ป ckas. Wlh
Figure 2-13 StarShip Advertisement by Shell Uotella and Airflow Truck Company
2.4.3 Tires
2.4.3.1 Improved Rolling Resistance
Research indicates that a tire's contribution to overall vehicle fuel efficiency is
approximately proportional to the vehicle weight on it.43 Energy loss associated with tires is
mainly due to deformation of the tires under the load of the vehicle, known as hysteresis, but
smaller losses result from aerodynamic drag, and other friction forces between the tire and road
surface and the tire and wheel rim. Collectively the forces that result in energy loss from the
tires are referred to as rolling resistance. Tires with higher rolling resistance lose more energy,
thus using more fuel and producing more CO2 emissions in operation, while tires with lower
rolling resistance lose less energy, and use less fuel, producing less CO2 emissions in operation.
A tire's rolling resistance is a factor considered in the design of the tire, and is affected by
the tread and casing compound materials, the architecture of the casing, tread design, and the tire
manufacturing process. It is estimated that 35 to 50 percent of a tire's rolling resistance is from
the tread and the other 50 to 65 percent is from the casing.43 Tire inflation can also impact
rolling resistance in that under-inflated tires can result in increased deformation and contact with
the road surface. In addition to the effect on CO2 emissions and fuel consumption, these design
and use characteristics of tires also influence durability, traction (both wet and dry grip), vehicle
handling, ride comfort, and noise. Tires that have higher rolling resistance are likely designed to
address one or more of these other tire attributes.
EPA's SmartWay program identified test methods and established criteria to designate
certain tires as having lower rolling resistance (LRR) for use in the program's emissions tracking
system, verification program, and SmartWay vehicle specifications. To measure a tire's
efficiency, the vertical load supported by the tire must be considered, because rolling resistance
is a function of the load on a tire. EPA uses a tire's rolling resistance coefficient (CRR) to
characterize LRR tires. CRR is measured using the ISO 28850 test method (see 40 CFR

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
1037.520(c),) and reported as the rolling resistance force over vertical load (kg/metric ton).
Differences in rolling resistance of up to 50 percent have been identified for tires designed to
equip the same vehicle.44
LRR tires are commercially available from most tire manufacturers and can be applied to
vehicles in all MD/HD classes. According to an energy audit conducted by Argonne National
Lab, tires were shown to be the second largest contributor to energy losses for a Class 6 delivery
truck at 50 percent load and speeds up to 35 mph (a typical average speed of urban delivery
vehicles).45 For Class 8 tractor-trailers, the share of vehicle energy required to overcome rolling
resistance is estimated at nearly 13 percent.46
NHTSA, EPA, and ARB met with stakeholders from the tire industry (Bridgestone,
Continental, Cooper, Goodyear, and Michelin) in 2014 to discuss the next generation of LRR
tires for the Phase 2 timeframe for all segments of Class 2b-8 vehicles, including trailers.
Manufacturers discussed forecasts for rolling resistance levels and production availability in the
Phase 2 timeframe, as well as their plans for improving rolling resistance performance while
maintaining other performance parameters such as traction, handling, wear, mass reduction,
retreadability, and structural durability.
The meetings included specific discussions of the impacts of the current generation of
LRR tires on vehicle stopping distance and handling. Manufacturers indicated no known safety
disbenefit in the current on-road fleet from use of LRR tires. While the next generation of tires
may require some tradeoffs in wear performance and costs over the next 10 years to achieve
better tire rolling resistance performance, manufacturers said they will not trade off safety for
performance. They also emphasized that keeping tires inflated (through proper maintenance or
automatic systems) was the best way to assure long term fuel efficiency and safety during
vehicle operation.
2.4.3.2 Wide Base Singles
Low rolling resistance tires can be offered for dual assembly tires and as wide base
singles (WBS). Wide base singles are primarily intended for combination tractor-trailers, but
some vocational vehicles are able to accommodate them. In the early years of this technology,
some states and local governments restricted use of WBS, but many of these restrictions have
since been lifted. As of December 2010, NACFE reports that there is virtual acceptance in North
America with only a few provinces in Canada that disallow or require special permitting for the use
of wide base tires.47 A wide base single is a larger tire with a lower profile. The common wide
base single sizes include 385/65R22.5, 425/65R22.5, 445/65R22.5, 435/50R22.5 and
445/50R22.5. Generally, a wide base single tire has less sidewall flexing compared to a dual
assembly and therefore less hysteresis occurs. Compared to a dual tire assembly, wide base
singles also produce less aerodynamic resistance or drag. Wide base singles can contribute to
improving a vehicle's fuel efficiency through design as a low rolling resistance tire and/or
through vehicle weight reduction.
According to one study, the use of fuel efficient wide base singles can reduce rolling
resistance by 3.7 to 4.9 percent compared to the most equivalent dual tire.48 An EPA study with
a tractor-trailer demonstrated an improvement in fuel consumption of 6 percent at 55 mph on the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
highway, 13 percent at 65 mph on the highway and 10 percent on a suburban loop49 using wide
base singles on the drive and trailer axles. EPA attributed the fuel consumption improvement to
the reduction in rolling resistance and vehicle weight reduction from using wide base singles. In
2008 the Department of Energy (DOE) compared the effect of different combinations of tires on
the fuel efficiency of Class 8 tractors. The data collected based on field testing indicates that
tractors equipped with wide base singles on the drive axle experience better fuel efficiency than
tractors equipped with dual tires, independent of the type of tire on the trailer.50 This study in
particular indicated a 6.2 percent improvement in fuel efficiency from wide base singles.
There is also a weight savings associated with wide base singles compared to dual tires.
Wide base singles can reduce a tractor and trailer's weight by as much as 1,000 lbs. when
combined with aluminum wheels. Bulk haulers of gasoline and other liquids recognize the
immediate advantage in carrying capacity provided by the reduction in the weight of tires and
have led the transportation industry in retrofitting their tractors and trailers.51
New generation wide base singles, which were first introduced in 2000, are designed to
replace a set of dual tires on the drive and/or trailer positions. They are designed to be
interchangeable with the dual tires without any change to the vehicle52. If the vehicle does not
have hub-piloted wheels, there may be a need to retrofit axle components.51'53 In addition to
consideration of hub/bearing/axle, other axle-end components may be affected by use of wide
base singles. To assure successful operation, suitable components should be fitted as
recommended by the vehicle manufacturer.54
Current wide base singles are wider than earlier models and legal in all 50 states for a 5-
axle, 80,000 GVWR truck 48 Wide base singles meet the "inch-width" requirements nationwide,
but are restricted in certain states up to 17,500 lbs. on a single axle at 500 lbs/inch width limit,
and are not allowed on single axle positions on certain double and triple combination vehicles52.
An inch-width law regulates the maximum load that a tire can carry as a function of the tire
width. Typically wide base singles are optimized for highway operation and not for city or
on/off highway operation. However, newer wide base singles are being designed for better scrub
resistance, which would allow an expansion of their use. The current market share of wide base
singles in combination tractor applications is 5 percent and the potential market is all
combination tractors.48 New generation wide base singles represent an estimated 0.5 percent of
the 17.5 million tires sold each year in the U.S.52
2.4.3.3 Tire Pressure Systems
Proper tire inflation is critical to maintaining proper stress distribution in the tire, which
reduces heat loss and rolling resistance. Tires with reduced inflation pressure exhibit more
sidewall flexing and tread shearing, resulting in greater rolling resistance than a tire operating at
its optimal inflation pressure. Bridgestone tested the effect of inflation pressure and found a 2
percent variation in fuel consumption over a 40 psi range.43 Tractor-trailers operating with all
tires under-inflated by 10 psi have been shown to increase fuel consumed by up to 1 percent.55
Tires can gradually lose pressure from small punctures, leaky valves or simply diffusion through
the tire casing. Changes in ambient temperature can also have an effect on tire pressure. Trailers
that remain unused for long periods of time between hauls may experience any of these

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
conditions. To achieve the intended fuel efficiency benefits of low rolling resistance tires, it is
critical that tires are maintained at the proper inflation pressure.
Although most truck fleets understand the importance of keeping tires properly inflated,
it is likely that a substantial proportion of trucks on the road have one or more underinflated tires.
An industry survey conducted in 2002 at two truck stops found that fewer than half of the tires
checked were within 5 pounds per square inch (psi) of their recommended inflation pressure.
Twenty-two percent of the vehicles checked had at least one tire underinflated by at least 20 psi,
and 4 percent of the vehicles were running with at least one flat tire, defined as a tire
underinflated by 50 psi or more. The survey also found mismatches in tire pressure exceeding 5
percent for dual tires on axle ends.56
A commercial vehicle tire condition study conducted by the Federal Motor Carrier Safety
Administration (FMCSA) in 2003 found similar indicators of poor tire inflation pressure
maintenance in commercial fleets. The FMCSA concluded that only 44 percent of all tires on
commercial vehicles were inflated within 5 psi of the recommended pressure, while over 7
percent of all tires in operation on commercial vehicles were underinflated by at least 20 psi. It
was also determined that the rates of tires used in dual assemblies that differed in pressure by
more than 5 psi was approximately 20 percent for tractor duals and 25 percent for trailer duals.
Finally, the FMCSA concluded that there were significant differences in tire inflation
maintenance practices between private and for-hire fleets, smaller and larger fleets, and local bus
and motor coach fleets.57
If drivers or fleets are not diligent about checking and attending to under-inflated tires,
the trailer may have much higher rolling resistance and much higher CO2 emissions and fuel
consumption. Proper tire inflation pressure can be maintained with a rigorous tire inspection and
maintenance program and EPA provides information on proper tire inflation pressure through its
SmartWay program.58 Tire pressure monitoring (TPM) and automatic tire inflation (ATI)
systems are designed to address under-inflated tires. Both systems alert drivers if a tire's
pressure drops below its set point. TPM systems monitor the tires and require user-interaction to
reinflate to the appropriate pressure. Yet unless the vehicle experiences a catastrophic tire
failure, simply alerting the driver that a tire's pressure is low may not necessarily result in action
to correct the problem. A driver may continue driving to their final destination before addressing
the tires, resulting in many miles of driving with improperly inflated tires. Current ATI systems
take advantage of trailers' air brake systems to supply air back into the tires (continuously or on
demand) until a selected pressure is achieved. In the event of a slow leak, ATI systems have the
added benefit of maintaining enough pressure to allow the driver to get to a safe stopping area.59
Estimates of the benefits of ATI systems vary depending on the base level of
maintenance already performed by the driver or fleet, as well as the number of miles the trailer
travels. Vehicles that are well maintained or that travel fewer miles would experience less
benefits from ATI systems compared to vehicles that log many miles or have a history of driving
with poorly inflated tires. The agencies believe ATI systems can provide a CO2 and fuel
consumption benefit to most tractors and trailers. Drivers and fleets that diligently maintain their
tires will spend less time and money to inspect each tire knowing that they are properly inflated.
Vehicles that have lower annual VMT due to long periods between uses would be less

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
susceptible to low tire pressures when they resume activity. Vehicles with high annual VMT
would experience the fuel savings associated with consistent tire pressures.
2.4.3.4 Retreaded Tires
The tread life of a tire is a measure of durability and some tires are designed specifically
for greater durability. Commercial vehicle tires are designed to be retreaded, a process in which
a new tread is bonded to the tire casing. The original tread of a tire will last anywhere from
100,000 miles to over 300,000 miles, depending on vehicle operation, original tread depth, tire
axle position, and proper tire maintenance. Retreading can extend the tire's useful life by
100,000 miles or more.60 In 2005, the Tire Industry Association estimated that approximately
17.6 million retreaded truck tires were sold in North America61.
All of the top commercial vehicle tire manufacturers are involved in tire retread
manufacturing. Bridgestone Bandag Tire Solutions accounts for 42 percent of the domestic
retreaded vehicle tire market with its Bandag retread products; Goodyear Tire and Rubber
Company accounts for 28 percent, mostly through its Wingfoot Commercial Tire Systems;
Michelin Retread Technologies Incorporated, with Megamile, Oliver, and Michelin retread
products, accounts for 23 percent. Other tire companies like Continental and independent retread
suppliers like Marangoni Tread North America (which also produces the Continental
"ContiTread" retread product) make up the remaining 7 percent.62 The retreading industry itself
consists of hundreds of retreaders who sell and service retreaded tires, often (but not always)
using machinery and practices identified with one of the major retread producers. There are
about 800 retread plants in North America.63 The top 100 retreaders in the U.S. retread 47,473
truck tires per day.
To maintain the quality of the casing and increase the likelihood of retreading, a tire
should be retreaded before the tread depth is reduced to its legal limit. At any time, steer tires
must have a tread depth of at least 4/32 of an inch and other tires, including drive tires and trailer
tires, must have a tread depth of at least 2/32 of an inch (49 CFR 393.75). Trucking fleets often
retread tires before tire treads reach this minimum depth in order to preserve the integrity of the
tire casing for retreading. If the casing remains in good condition, a truck tire can be safely
retreaded multiple times. Heavy truck tires in line haul operation can be retread 2 to 3 times and
medium-duty truck tires in urban use can be retread 5 or more times.64 To accommodate this
practice, many commercial vehicle tire manufacturers warranty their casings for up to five years,
excluding damage from road hazards or improper maintenance.
To protect the casing, a steer tire is generally retreaded once the tread is worn down to
6/32 of an inch and a drive tire is retreaded once the tread is worn down to 8/32 of an inch.65
Tires used on Class 8 vehicles are retreaded as many as three times.
Both the casing and the tread contribute to a tire's rolling resistance. It is estimated that
35 to 50 percent of a tire's rolling resistance is the result of the tread. Differences in drive tire
rolling resistance of up to 50 percent for the same casing with various tread compounds have
been demonstrated. For example, a fuel efficient tread (as defined by the manufacturer) was
added to two different casings resulting in an average increase in rolling resistance of 48 percent.
When a nonfuel efficient tread (also defined by the manufacturer) was added to the same casings,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
the rolling resistance increased by 125 percent on average. This characterizes the effect of the
tread on the rolling resistance of a tire.
Because tires can be retreaded multiple times, changes in the casing due to wear, damage
and material aging may impact rolling resistance to a greater degree than would occur in an
original tire. Additionally, as evidenced above, if a tread compound different than the original
tread is used, a retreaded tire can have higher or lower rolling resistance than the original tire.
Since the agencies have no way of knowing whether the rolling resistance of retreaded tires will
be higher or lower than the rolling resistance of the original tires, we similarly have no way of
knowing whether low rolling resistance tire benefits will continue to accrue for a vehicle's entire
lifetime.
2.4.4 Transmissions
Transmissions are a significant vehicle component. They are part of the drivetrain, which
also includes axles and tires. Ways to improve transmissions include electronic controls, shift
strategy, gear efficiency, and gear ratios. The relative importance of having an efficient
transmission increases when vehicles operate in conditions with a higher shift density. Each
shift represents an opportunity to lose speed or power that would have to be regained after the
shift is completed. Further, each shift engages gears that have their own inherent inefficiencies.
Optimization of vehicle gearing to engine performance through selection of transmission
gear ratios, final drive gear ratios and tire size can play a significant role in reducing fuel
consumption and GHGs. Optimization of gear selection versus vehicle and engine speed
accomplished through driver training or automated transmission gear selection can provide
additional reductions. The 2010 NAS report found that the opportunities to reduce fuel
consumption in heavy-duty vehicles due to transmission and driveline technologies in the 2015
time frame ranged between 2 and 8 percent.66
The design goal is for the transmission to deliver the needed power to the vehicle while
maintaining engine operation within the engine's "sweet spot" for most efficient operation.
Truck and chassis manufacturers today offer a wide range of tire sizes, final gear ratios and
transmission choices so that owners can work with application engineers to specify an optimal
combination given the intended vehicle service class and other performance needs.
2.4.4.1 Optimizing Number of Gears and Gear Ratios
Manufacturers of light and medium heavy-duty vehicles can choose to replace 6-speed
transmissions with 8-speed or more automatic transmissions. Additional ratios allow for further
optimization of engine operation over a wider range of conditions, but this is subject to
diminishing returns as the number of speeds increases. As additional planetary gear sets are
added (which may be necessary in some cases to achieve the higher number of ratios), additional
weight and friction are introduced. Also, the additional shifting of such a transmission can be
perceived as bothersome to some consumers, so manufacturers need to develop strategies for
smooth shifts.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The Phase 1 rulemaking projected that 8-speed transmissions could incrementally reduce
fuel consumption by 1 to 3 percent from a baseline 6-speed automatic transmission over some
test cycles. The SwRI report uses 2 to 3 percent fuel consumption reduction when replacing 6-
speed baseline automatic transmissions with improved 8-speed automatic transmissions. Chapter
2.9 of the RIA outlines the agencies' updated analysis that takes into account public comments
on the proposal.
2.4.4.2	Gear Efficiencies
As described elsewhere for axles and engines, the efficiency of gears can be improved by
reducing friction and minimizing mechanical losses. This can be done by reducing the friction
between the two gears in contact. This friction is reduced mainly by improving the surface finish
of the gears. The other way of doing is by reducing the amount of distance the gear faces are
sliding against each other.
2.4.4.3	Shift Strategies
Calibrating the transmission shift schedule to upshift earlier and quicker, and to lock up
or partially lock up the torque converter under a broader range of operating conditions can
reduce fuel consumption and CO2 emissions. However, this operation can result in a perceptible
degradation in noise, vibration, and harshness. The degree to which NVH can be degraded
before it becomes noticeable to the driver is strongly influenced by characteristics of the vehicle,
and although it is somewhat subjective, it always places a limit on how much fuel consumption
can be improved by transmission control changes.
During operation, an automatic transmission's controller manages the operation of the
transmission by scheduling the upshift or downshift, and locking or allowing the torque
converter to slip based on a preprogrammed shift schedule. The shift schedule contains a
number of lookup table functions, which define the shift points and torque converter lockup
based on vehicle speed and throttle position, and other parameters such as temperature.
Aggressive shift logic can be employed in such a way as to maximize fuel efficiency by
modifying the shift schedule to upshift earlier and inhibit downshifts under some conditions,
which reduces engine pumping losses and engine friction. The application of this technology
does require a manufacturer to confirm that drivability, durability, and NVH are not significantly
degraded.
A torque converter is a fluid coupling located between the engine and transmission in
vehicles with automatic transmissions and continuously-variable transmissions (CVT). This
fluid coupling allows for slip so the engine can run while the vehicle is idling in gear (as at a stop
light), provides for smoothness of the powertrain, and also provides for torque multiplication
during acceleration, and especially launch. During light acceleration and cruising, the inherent
slip in a torque converter causes increased fuel consumption, so modern automatic transmissions
utilize a clutch in the torque converter to lock it and prevent this slippage. Fuel consumption can
be further reduced by locking up the torque converter at lower vehicle speeds, provided there is
sufficient power to propel the vehicle, and noise and vibration are not excessive. If the torque
converter cannot be fully locked up for maximum efficiency, a partial lockup strategy can be
employed to reduce slippage. Early torque converter lockup is applicable to all vehicle types

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
with automatic transmissions. Some torque converters would require upgraded clutch materials
to withstand additional loading and the slipping conditions during partial lock-up. As with
aggressive shift logic, confirmation of acceptable drivability, performance, durability and NVH
characteristics would be required to successfully implement this technology.
2.4.4.4 Architectures
The manual transmission architecture has traditionally been considered the most efficient
architecture since it did not experience the losses inherent in a torque converter required on a
traditional automatic transmission (a traditional automatic transmission being a transmission with
fully automated shifting and using a hydraulic lock-up torque converter for smooth vehicle
launching from a stop). However, this traditional understanding has been called into question as
advances in electronics and computer processing power allow for more efficiency from a manual
transmission architecture with fully automated shifting. The two primary manual transmission
architectures employing automated shifting are the automated manual transmission (AMT) and
the dual-clutch transmission (DCT). When implemented well, these mechanically more efficient
designs could inherently provide better fuel efficiency and lower greenhouse gas emissions than
conventional torque converter automatic transmission designs and, potentially, even fully manual
transmissions. These transmissions offer the inherently lower losses of a manual transmission
with the efficiency and shift quality advantages of electronic controls. The lower losses stem
from the elimination of the conventional lock-up torque converter, and a greatly reduced need for
high pressure hydraulic circuits to hold clutches to maintain gear ratios (in automatic
transmissions).
2.4.4.4.1	AMT
An AMT is mechanically similar to a conventional manual transmission, but shifting and
launch functions are automatically controlled by electronics. The term AMT generally refers to
a single clutch design (differentiating it from a dual-clutch transmission, or dual-clutch AMT,
described below) which is essentially a manual transmission with automated clutch and shifting.
Because of shift quality issues with single-clutch designs, dual-clutch designs are more common
in light-duty applications where driver acceptance is of primary importance. In the HD sector,
shift quality remains important but is less so when compared to light-duty. As a result, the
single-clutch AMT architecture can be an attractive technology for HD vehicles.
2.4.4.4.2	DCT
A DCT uses separate clutches (and separate gear shafts) for the even-numbered and the
odd-numbered gears. In this way, the next expected gear is pre-selected thereby allowing for
faster and smoother shifting. For example, in a 6 speed DCT, if the vehicle is accelerating in
third gear, the shaft with gears one, three and five has gear three engaged and is transmitting
power to the wheels. The shaft with gears two, four, and six is idle but has gear four engaged.
When a shift is required, the controller disengages the odd-gear clutch while simultaneously
engaging the even-gear clutch, thus making a smooth shift. If, on the other hand, the driver
slows the vehicle instead of continuing to accelerate, the transmission would have to change to
second gear on the idling shaft to anticipate a downshift. This shift can be made quickly on the
idling shaft since there is no torque being transferred on it.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
There are variations of the DCT design, with some having wet clutches and some dry
clutches, and more recent versions that incorporate a torque converter similar to but smaller than
the torque converter of a traditional automatic transmission. The wet clutch designs offer a
higher torque capacity that comes from the use of a hydraulic system that cools the clutches.
Wet clutch systems are also less efficient than dry clutch systems due to the losses associated
with the hydraulic pumping. They also are more costly due to the hydraulics.
2.4.4.5 Hybrid Powertrain Systems
The industry is currently developing many variations of hybrid powertrain systems. The
fully integrated hybrids developed to date have seen fuel consumption and CO2 emissions
reductions between 20 and 50 percent in the field where they are used in high kinetic intensity
applications. However, there are still some key issues that are restricting the penetration of
hybrids, including overall system cost, battery technology, and lack of cost-effective electrified
accessories.
A hybrid vehicle is a vehicle that combines two significant sources of propulsion energy,
where one uses a consumable fuel (like diesel), and one is rechargeable (during operation, or by
another energy source). Hybrid technology is well established in the U.S. light-duty market,
some manufacturers have been producing heavy-duty hybrid models for many years, and others
are looking to develop hybrid models in future years.
Hybrids reduce fuel consumption through three major mechanisms:
The internal combustion engine can be optimized (through downsizing, modifying
the operating cycle, or other control techniques) to operate at or near its most
efficient point more of the time. Power loss from engine downsizing can be
mitigated by employing power assist from the secondary power source.
Some of the energy normally lost as heat while braking can be captured and
stored in the energy storage system for later use.
The engine is turned off when it is not needed, such as when the vehicle is
coasting or when stopped.
Hybrid vehicles utilize some combination of these three mechanisms to reduce fuel
consumption and CO2 emissions. The effectiveness of fuel consumption and CO2 reduction
depends on the utilization of the above mechanisms and how aggressively they are pursued. One
area where this variation is particularly prevalent is in the choice of engine size and its effect on
balancing fuel economy and performance. Some manufacturers choose not to downsize the
engine when applying hybrid technologies. In these cases, performance is vastly improved,
while fuel efficiency improves significantly less than if the engine were downsized to maintain
the same performance as the conventional version. The non-downsizing approach is used for
vehicles where towing and/or hauling are an integral part of their performance requirements. In
these cases, if the engine is downsized, the battery can be quickly drained during a long hill
climb with a heavy load, leaving only a downsized engine to carry the entire load. Because
towing capability is currently a heavily-marketed HD pickup truck attribute, manufacturers are

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
hesitant to offer a truck with a downsized engine that can lead to a significantly diminished
towing performance when the battery state of charge level is low, and therefore engines are
traditionally not downsized for these vehicles. In assessing the cost of hybrid technology for
heavy duty vehicles, the agencies have assumed that engines will not be downsized.
Strong hybrid technology utilizes an axial electric motor connected to the transmission
input shaft and connected to the engine crankshaft through a clutch. The axial motor is a
motor/generator that can provide sufficient torque for launch assist, all electric operation, and the
ability to recover significant levels of braking energy.
A hybrid drive unit is complex and consists of discrete components such as the electric
traction motor, transmission, generator, inverter, controller and cooling devices. Certain types of
drive units may work better than others for specific vehicle applications or performance
requirements. Several types of motors and generators have been developed for hybrid-electric
drive systems, many of which merit further evaluation and development on specific applications.
Series HEVs typically have larger motors with higher power ratings because the motor alone
propels the vehicle, which may be applicable to Class 3-5 applications. In parallel hybrids, the
power plant and the motor combine to propel the vehicle. Motor and engine torque are usually
blended through couplings, planetary gear sets and clutch/brake units. The same mechanical
components that make parallel heavy-duty hybrid drive units possible can be designed into series
hybrid drive units to decrease the size of the electric motor(s) and power electronics.
An electrical energy storage system is needed to capture energy from the generator, to
store energy captured during vehicle braking events, and to return energy when the driver
demands power. This technology has seen a tremendous amount of improvement over the last
decade and recent years. Advanced battery technologies and other types of energy storage are
emerging to give the vehicle its needed performance and efficiency gains while still providing a
product with long life. The focus on the more promising energy storage technologies such as
nickel metal-hydride (NiMH) and lithium technology batteries along with ultra-capacitors for the
heavy-duty fleet should yield interesting results after further research and applications in the
light-duty fleet.
Heavy-duty hybrid vehicles also use regenerative braking for improved fuel economy,
emissions, brake heat, and wear. A conventional heavy vehicle relies on friction brakes at the
wheels, sometimes combined with an optional engine retarder or driveline retarder to reduce
vehicle speed. During normal braking, the vehicle's kinetic energy is wasted when it is
converted to heat by the friction brakes. The conventional brake configuration has large
components, heavy brake heat sinks, and high temperatures at the wheels during braking, audible
brake squeal, and consumable components requiring maintenance and replacement. Hybrid
electric systems recover some of the vehicle's kinetic energy through regenerative braking,
where kinetic energy is captured and directed to the energy storage system. The remaining
kinetic energy is dissipated through conventional wheel brakes or in a driveline or transmission
retarder. Regenerative braking in a hybrid electric vehicle can require integration with the
vehicle's foundation (friction) braking system to maximize performance and safety.
Today's systems function by simultaneously using the regenerative features and the
friction braking system, allowing only some of the kinetic energy to be saved for later use.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Optimizing the integration of the regenerative braking system with the foundation brakes would
increase the benefits and is a focus for continued work. This type of hybrid regenerative braking
system improves fuel economy, GHG emissions, brake heat, and wear.
In a hydraulic hybrid system, deceleration energy is taken from the drivetrain by an inline
hydraulic pump/motor unit by pumping hydraulic fluid into high pressure cylinders. The fluid,
while not compressible, pushes against a membrane in the cylinder that compresses an inert gas
to 5,000 PSI or more when fully charged. Upon acceleration, the energy stored in the
pressurized tank pushes hydraulic fluid back into the drivetrain pump/motor unit, allowing it to
motor into the drivetrain and assist the vehicle's engine with the acceleration event. This heavy-
duty vehicle hybrid approach has been demonstrated successfully, producing good results on a
number of commercial and military trucks.
Despite the significant future potential for hybrids discussed above, there are no simple
solutions applicable for each heavy-duty hybrid application due to the large vocational vehicle
fleet variation. A choice must be made relative to the requirements and priorities for the
application. Challenges in motor subsystems such as gear reductions and cooling systems must
be considered when comparing the specific power, power density, and cost of the motor
assemblies. High speed motors can significantly reduce weight and size, but they require speed
reduction gear sets that can offset some of the weight savings, reduce reliability and add cost and
complexity. Air-cooled motors are simpler and generally less expensive than liquid cooled
motors, but they are larger and heavier, and they require access to ambient air, which can carry
dirt, water, and other contaminants. Liquid-cooled motors are generally smaller and lighter for a
given power rating, but they may require more complex cooling systems that can be avoided
with air-cooled versions. Various coolant options, including water, water-glycol, and oil, are
available for liquid-cooled motors but must be further researched for long term durability.
Electric motors, power electronics, electrical safety, regenerative braking, and power-plant
control optimization have been identified as the most critical technologies requiring further
research to enable the development of higher efficiency hybrid electric propulsion systems.
2.4.5 Axles
2.4.5.1 Axle Efficiency
Axle efficiency is improved by reducing generally two categories of losses; mechanical
losses and spin losses.
Mechanical losses can be reduced by reducing the friction between the two gears in
contact. This friction is reduced mainly by improving the surface finish of the gears. The other
way of doing this by reducing the amount of distance the gear faces are sliding against each
other. Generally speaking frictional losses are proportional to the torque on the axle not a
function of rotational speed of the axle.
Spin losses on the other hand are a function of speed and not torque. One of the main
ways to reduce the spin losses of the axle is by using a lower viscosity lubricant. Some high-
performance lower viscosity formulations have been designed to have superior performance at
high operating temperatures, and may have extended change intervals.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
A study conducted by researchers at Shell Global Solutions on a Mercedes Benz OM
460LA heavy-duty diesel engine run under the World Harmonized Transient Cycle (WHTC) and
World Harmonized Stationary Cycle (WHSC), used a combination of a SAE 5W-30 engine oil,
SAE 75W-80 gearbox oil and SAE 75W-90 axle oil. The combination yielded average fuel
economy improvements of 1.8 percent over the WHTC and 1.1 percent over the WHSC, relative
to a SAE 15W-40 engine oil, SAE 80W gearbox and SAE 90 axle oil [VT-27], The baseline
lubricants represent current mainstream products, and the new lubricants were top-tier
formulations focusing on modified viscometric effects. Using the WHSC cycle, significant
variations in the individual lubricant contribution under different speed and load conditions
within the cycle were identified. Additionally, an average fuel economy improvement of 1.8
percent was observed using medium-duty trucks under a range of typical European driving
conditions in a controlled field trial.67
Spin losses can also be reduced by lowering the volume of lubricant in the sump. This
reduces the surface area of the gears that are churning through the lubricant. One of the main
challenges of doing this is making sure that there is still adequate coverage of lubricant on the
gears and bearings as well as adequate circulation so that the lubricant temperature does not rise
too high and accelerate the aging of the lubricant.
If a manufacturer wishes to demonstrate a benefit specific to any technology that
improves axle efficiency, an axle efficiency test can be performed and input into GEM. See RIA
Chapter 3 for a description of the test procedure for axle efficiency.
2.4.5.2	Gear Ratio
Combining with transmission ratio, selection of the axle ratio can play a significant role
in vehicle performance. For an on-highway tractor, the axle ratio must be selected in such a way
that the engine can constantly run inside the sweet spot, where the engine efficiency is optimal
for a typical constant cruise speed like 65 miles per hour. Although many vehicles on the road
already use a fast axle ratio as low as 2.64:1 with the direct drive of transmission, which moves
the engine speed in the range of 1200 rpm or even lower, most vehicles still use higher or slower
axle ratio, which puts the engine speed in the range of 1300-1400 rpm. In order to take
advantage of optimal engine speed, which is typically in the range of 1100-1150 rpm for HHD
diesel vehicles, it is expected that a faster axle ratio lower than 2.64:1 would be widely used in
2018 and beyond for tractors. Furthermore, in order to enhance vehicle performance, many axle
manufacturers are developing dual speed axles, allowing vehicles to switch to a higher axle ratio
during transient driving conditions, such as city traffic. On the vocational side, the ability to start
a heavy vehicle, climb hills, and operate smoothly at low speed is strongly influenced by axle
ratio, and therefore, one can see a large variation of axle ratios depending on the application.
2.4.5.3	Tandem Drive Axle Improvements
Manufacturers are developing technologies to enable heavy trucks with two rear drive
axles to be driven solely by the lead rear axle either permanently or on a part time basis.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.4.5.3.1	6x2
Most tractors and heavy heavy-duty vocational vehicles today have three axles - a steer
axle and two rear drive axles, which is commonly referred to as a 6x4 configuration.
Manufacturers offer 6x2 tractors that include one rear drive axle and one rear non-driving axle.
The 6x2 tractors offer three distinct benefits. First, the non-driving rear axle does not have
internal friction and therefore reduces the overall parasitic losses in the drivetrain. In addition,
the 6x2 configuration typically weighs approximately 300 to 400 pounds less than a 6x4
configuration.68 Finally, the 6x2 typically costs less or is cost neutral when compared to a 6x4
tractor. Sources cite the effectiveness of 6x2 axles at between 1 and 3 percent.69 Similarly, with
the increased use of double and triple trailers, which reduce the weight on the tractor axles when
compared to a single trailer, manufacturers offer 4x2 axle configurations. The 4x2 axle
configuration would have as good as or better fuel efficiency performance than a 6x2.
2.4.5.3.2	Enhanced 6x2
One of the drawbacks of 6x2 axle is lack of traction, specifically during the winter
condition and high grade road when the road is slippery. In order to overcome this deficiency,
some axle manufacturers offer products that perform similar to the 6x4 configurations.
SMARTandem offered by Meritor is just one of the examples.70 In this system, the axle runs
6x2 for most time. Once the conditions that require more traction are experienced, the vehicle
activates the system to add more loads into one the powered axle, thus instantly increasing
traction. This system offers weight savings in the range of 300 to 400 lbs, as well as 2 percent
fuel saving when compared to a conventional 6x4 axle.
2.4.5.3.3	Part Time 6x2 Axle
Based on confidential stakeholder discussions, the agencies anticipate that the axle
market may offer, in the time frame of Phase 2, a Class 8 version of the type of axle disconnect
that today allows 4x4 operators of HD pickup trucks to automatically disconnect or reconnect the
front axle depending on needs for traction in varying driving conditions. The Class 8 version
would likely function for the two tandem drive axles in a similar manner as the HD pickup trucks
do for the front axle. The switching could be automated or user-commanded. In these cases, the
axle actuator housing, sometimes called the axle disconnect housing, is part of the differential
that houses the gears and shift fork required to lock two axles together. The axle actuator works
together with the transfer case to send torque to all four wheel-ends. Recently, Dana Holding
Corporation has developed an axle system that switches between the two modes based on driving
conditions to maximize driveline efficiency.71 When high traction is required, the system
operates in 6x4 mode. When 6x4 tractive effort is not required, the system operates in 6x2
mode. It is reported that this type of system can offer a benefit of 2.5 percent.
In the 4x4 example, the transfer case connects the input from the transmission to the rear
and front driveshafts. The axle actuator housing is found on the differential. In the 4x4 example,
a shift fork inside the axle actuator housing slides a locking collar over two gears locking both
driver and passenger side axles together. In some 4x4 vehicles, those with automatic 4WD, this
process occurs automatically. In others, with selective 4WD, the driver can choose to engage
4WD or RWD with a switch. These have slightly different axle actuator housings and have

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
actuator solenoids mounted to them.72 These systems would not provide the weight reduction
benefit of the permanent 6x2 configuration, and may offer less fuel savings, especially with
operator-switchable systems.
2.4.6 Weight Reduction
Mass reduction is a technology that can be used in a manufacturer's strategy to meet the
Phase 2 standards (although the agencies are not predicating the standards on use of downsizing).
Vehicle mass reduction (also referred to as "light-weighting"), decreases fuel consumption and
GHG emissions by reducing the energy demand needed to overcome inertia forces, and rolling
resistance. Reduced mass in heavy-duty vehicles can benefit fuel efficiency and CO2 emissions
in two ways. If a truck is running at its gross vehicle weight limit with high density freight, more
freight can be carried on each trip, increasing the truck's ton-miles per gallon. If the vehicle is
carrying lower density freight and is below the GVWR (or GCW) limit, the total vehicle mass is
decreased, reducing rolling resistance and the power required to accelerate or climb grades.
Many vehicle components are typically made of heavier material, such as traditional steel.
Manufacturers have worked with mass reduction technologies for many years and a lot of these
technologies have been used in production vehicles. The weight savings achieved by adopting
mass reduction technologies offset weight gains due to increased vehicle size, larger powertrains,
and increased feature content (sound insulation, entertainment systems, improved climate
control, etc.). Generally, an empty truck contributes to about one-third of the total vehicle
weight. Every 10 percent drop in vehicle weight reduces fuel use about 5 percent.73
Although many gains have been made to reduce vehicle mass, many of the features being
added to modern tractors to benefit fuel efficiency, such as additional aerodynamic features or
idle reduction systems, have the effect of increasing vehicle weight, causing mass to stay
relatively constant. Material and manufacturing technologies can also play a significant role in
vehicle safety by reducing vehicle weight, and in the improved performance of vehicle passive
and active safety systems. Hybrid powertrains, fuel cells and auxiliary power would not only
present complex packaging and weight issues, they would further increase the need for
reductions in the weight of the body, chassis, and powertrain components in order to maintain
vehicle functionality.
Manufacturers may employ a systematic approach to mass reduction, where the net mass
reduction is the addition of a direct component or system mass reduction, also referred to as
primary mass reduction, plus the additional mass reduction taken from indirect ancillary systems
and components, also referred to as secondary mass reduction or mass compounding.
Mass reduction can be achieved through a number of approaches, even while maintaining
other vehicle functionalities. As summarized by NAS in its 2011 light duty vehicle report, there
are two key strategies for primary mass reduction: 1) substituting lighter materials for heavier
materials; and 2) changing the design to use less material.74

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.4.6.1 Material Substitution
Substitution of a material used in an assembly or a component for one with lower density
and/or higher strength includes replacing a common material such as mild steel with higher-
strength and advanced steels, aluminum, magnesium, and composite materials. In practice,
material substitution tends to be quite specific to the manufacturer and situation. Some materials
work better than others for particular vehicle components, and unless strength is matched, some
substituted components may need to be more numerous (i.e. two brackets instead of one).
Further, one choices of material may lead a manufacturer to invest more heavily in adjusting its
manufacturing process to its properties, thus possibly impeding its ability to consider other
materials. The agencies recognize that like any type of mass reduction, material substitution has
to be conducted not only with consideration to maintaining equivalent component strength, but
also to maintaining all the other attributes of that component, system or vehicle, such as
crashworthiness, durability, and noise, vibration and harshness (NVH).
One example that combines material substitution with component-elimination is the use
of wide-based single tires and aluminum rims to replace traditional dual tires and rims,
eliminating eight steel rims and eight tires from a tractor. Using aluminum, metal alloys, metal
matrix composites, and other lightweight components where appropriate can reduce empty
vehicle weight (known as "tare weight"), improve fuel efficiency, and reduce greenhouse gas
emissions. In addition, in weight-sensitive applications, lightweight components can allow more
cargo and increased productivity. A report by the National Commission on Energy Policy
estimates that a fuel economy gain of 5.0 percent on certain applications could be achieved by
vehicle mass reduction further illustrating the fuel economy gains possible on heavy-duty
applications.75 A report for the U.S. DOT estimated potential reductions in modal GHG
emissions are 4.6 percent, though it also found that current light-weight materials are costly and
are application- and vehicle-specific with need for further research and development for
advanced materials.76
The principal barriers to overcome in reducing the weight of heavy vehicles are
associated with the cost of lightweight materials, the difficulties in forming and manufacturing
lightweight materials and structures, the cost of tooling for use in the manufacture of relatively
low-volume vehicles (when compared to automotive production volumes), and ultimately, the
extreme durability requirements of heavy vehicles. While light-duty vehicles may have a life
span requirement of several hundred thousand miles, typical heavy-duty commercial vehicles
must last over 1 million miles with minimum maintenance, and often are used in secondary
applications for many more years. This requires high strength, lightweight materials that provide
resistance to fatigue, corrosion, and can be economically repaired. Additionally, because of the
limited production volumes and the high levels of customization in the heavy-duty market,
tooling and manufacturing technologies that are used by the light-duty automotive industry are
often uneconomical for heavy vehicle manufacturers. Lightweight materials such as aluminum,
titanium and carbon fiber composites provide the opportunity for significant weight reductions,
but their material cost and challenging forming and manufacturing requirements make it difficult
for them to compete with low-cost steels. In addition, although mass reduction is currently
occurring on both vocational vehicles and line haul tractor-trailers, the addition of other systems
for fuel economy, performance or comfort increases the vehicle mass offsetting the mass
reduction that has already occurred, thus it is not captured in the overall vehicle mass

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
measurement (e.g. 500 lbs for WHR). Most vehicle manufacturers offer lightweight tractor
models that are 1,000 or more pounds lighter than comparable models. Lighter-weight models
combine different weight-saving options that may include:77
•	Cast aluminum alloy wheels can save up to 40 pounds each for total savings of 400
pounds
•	Aluminum axle hubs can save over 120 pounds compared to ductile iron or steel
•	Centrifuge brake drums can save nearly 100 pounds compared to standard brake drums
•	Aluminum clutch housing can save 50 pounds compared to iron clutch housing
•	Composite front axle leaf springs can save 70 pounds compared to steel springs
•	Aluminum cab frames can save hundreds of pounds compared to standard steel frames
2.4.6.2 Synergistic Effects - Reduced Power Demand
Manufacturers employ a systematic approach to mass reduction, where the net mass
reduction is the addition of a direct component or system mass reduction plus the additional mass
reduction that can be taken from indirect ancillary systems and components, as a result of full
vehicle optimization, effectively compounding or obtaining a secondary mass reduction from a
primary mass reduction. The strategy of using less material compared to the baseline component
or system can be achieved by optimizing the design and structure of vehicle components,
systems and vehicle structure. Vehicle manufacturers have long used these continually-
improving CAE tools to optimize vehicle designs. For example, the Future Steel Vehicle (FSV)
project sponsored by World Auto Steel used three levels of optimization: topology optimization,
low fidelity 3G (Geometry, Grade, and Gauge) optimization, and subsystem optimization, to
achieve 30 percent mass reduction in the body structure of a vehicle with a mild steel unibody
structure.78 Using less material can also be achieved through improving the manufacturing
process, such as by using improved joining technologies and parts consolidation. This method is
often used in combination with applying new materials.
If vehicle mass is reduced sufficiently through application of the two primary strategies
of using less material and material substitution described above, secondary mass reduction
options may become available. Secondary mass reduction is enabled when the load requirements
of a component are reduced as a result of primary mass reduction. If the primary mass reduction
reaches a sufficient level, a manufacturer may use a smaller, lighter, and potentially more
efficient powertrain while maintaining vehicle performance. If a powertrain is downsized, a
portion of the mass reduction may be attributed to the reduced torque requirement that results
from the lower vehicle mass. The lower torque requirement enables a reduction in engine
displacement, changes to transmission torque converter and gear ratios, and changes to the final
drive gear ratio. The reduced powertrain torque may enable the downsizing and/or mass
reduction of powertrain components and accompanying reduced rotating mass (e.g., for
transmission, driveshafts/halfshafts, wheels, and tires) without sacrificing powertrain durability.
However, there may be trade-offs, as it is possible that use of a downsized engine may require a
transmission with more gears. The combined mass reductions of the engine, drivetrain, and body
would reduce stresses on the suspension components, steering components, wheels, tires, and
brakes, which can allow further reductions in the mass of these subsystems. Reducing the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
unsprung masses such as the brakes, control arms, wheels, and tires further reduce stresses in the
suspension mounting points, which would allow for further optimization and potential mass
reduction.
One example of a synergistic effect is rotational inertia. Reducing the weight of rotating
components provides an enhanced fuel efficiency benefit over reducing the weight of static
components. In theory, as components such as brake rotors, brake drums, wheels, tires,
crankshafts, camshafts, and piston assemblies become lighter, the power consumption to rotate
the masses would be directly proportional to the mass decrease. Using physical properties of a
rotating component such as a wheel, it is relatively straightforward to calculate an equivalent
mass. However, we do not have enough information to derive industry average values for
equivalent mass, nor have we evaluated the best way for GEM to account for this. Using typical
values for a heavy-duty steel wheel compared to a similar-sized aluminum wheel, the agencies
estimate the equivalent mass ratio is in the range of 1.2 to 1.3. That means that by reducing the
mass of a wheel by 20 pounds, the vehicle could theoretically perform as if 26 pounds had been
reduced.
Estimates of the synergistic effects of mass reduction and the compounding effect that
occurs along with it can vary significantly from one report to another. For example, in
discussing its estimate, an Auto-Steel Partnership report states that "These secondary mass
changes can be considerable—estimated at an additional 0.7 to 1.8 times the initial mass
change."79 This means for each one pound reduction in a primary component, up to 1.8 pounds
can be reduced from other structures in the vehicle (i.e., a 180 percent factor). The report also
discusses that a primary variable in the realized secondary weight reduction is whether or not the
powertrain components can be included in the mass reduction effort, with the lower end
estimates being applicable when powertrain elements are unavailable for mass reduction.
However, another report by the Aluminum Association, which primarily focuses on the use of
aluminum as an alternative material for steel, estimated a factor of 64 percent for secondary mass
reduction even though some powertrain elements were considered in the analysis.80 That report
also notes that typical values for this factor vary from 50 to 100 percent. Although there is a
wide variation in stated estimates, synergistic mass reductions do exist, and the effects result in
tangible mass reductions. Mass reductions in a single vehicle component, for example a door
side impact/intrusion system, may actually result in a significantly higher weight savings in the
total vehicle, depending on how well the manufacturer integrates the modification into the
overall vehicle design. Accordingly, care must be taken when reviewing reports on weight
reduction methods and practices to ascertain if compounding effects have been considered or not.
2.4.7 Vehicle Speed Limiter
The power required to move a vehicle increases as the vehicle speed increases.
Travelling at lower speeds provides additional efficiency to the vehicle performance. Most
vehicles today have the ability to electronically control the maximum vehicle speed through the
engine controller. This feature is used today by fleets and owners to provide increased safety
and fuel economy. Currently, these features are designed to be able to be changed by the owner
and/or dealer.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The impact of this feature is dependent on the difference between the governed speed and
the speed that would have been travelled, which is dependent on road type, state speed limits,
traffic congestion, and other factors. The agencies assess the benefit of a vehicle speed limiter
by reducing the maximum drive cycle speed on the 65 mph Cruise mode of the cycle. The
maximum speed of the drive cycle is 65 mph, therefore any vehicle speed limit with a setting
greater than this would show no benefit for purposes of these regulations, but may still show
benefit in the real world in states where the interstate truck speed limit is greater than the
national average of 65.5 mph.
The benefits of this simple technology are widely recognized. The American Trucking
Association (ATA) developed six recommendations to reduce carbon emissions from trucks in
the United States. Their first recommendation is to enact a national truck speed limit of 65 mph
and require that trucks manufactured after 1992 have speed governors set at not greater than 65
mph.81 The SmartWay program includes speed management as one of their key Clean Freight
Strategies and provides information to the public regarding the benefit of lower highway
speeds.82
Some countries have enacted regulations to reduce truck speeds. For example, the United
Kingdom introduced regulations in 2005 which require new trucks used for goods movement to
have a vehicle speed limiter not to exceed 90 km/hr (56 mph).83 The Canadian Provinces of
Ontario and Quebec developed regulations which took effect in January 2009 that requires on-
highway commercial heavy-duty trucks to have speed limiters which limit the truck's speed to
105 km/hr (65 mph).84
Many truck fleets consider speed limiter application a good business practice in their
operations. A Canadian assessment of heavy-duty truck speed limiters estimated that 60 percent
of heavy truck fleets in North America use speed limiters.84 Con Way Freight, Con Way
Truckload, and Wal-Mart currently govern the speeds of their fleets between 62 and 65 mph.85
A potential disbenefit of this technology is the additional time required for goods
movement, or loss of productivity. The elasticity between speed reduction and productivity loss
has not been well defined in industry. The Canadian assessment of speed limiters cited above
found that the fuel savings due to the lower operating speeds outweigh any productivity losses.
A general consensus among the OEMs is that a 1 percent decrease in speed might lower
productivity by approximately 0.2 percent.85
In Phase 1, the agencies did not premise the tractor standards on a technology package
that included VSL. Vehicle speed limiters are a technology recognized in Phase 1 GEM, but
manufacturers are not opting to use the tamper-resistant VSLs as a strategy for complying with
the early years of Phase 1 CO2 emissions and fuel consumption standards.
The impact of VSL set to 55 mph of a typical high roof tractor-trailer is approximately 7
percent for day cabs and 10 percent for sleeper cabs, as shown below in Figure 2-14.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
12.0%
-5 10.0%
CD
c
O
U
~cD
=3
u_
"O
c
rvi
O
U
NP
0s-
3.0%
6.0%
4.0%
2.0%
0.0%
54
Vehicle Speed Limiter Effectiveness
Composite Result
-Sleeper Cab
ฆ Day Cab
56	58	60	62
Vehicle Speed Limiter Setting (mph)
64
66
Figure 2-14 Vehicle Speed Limiter Effectiveness in Tractors
2.4.8 Reduced Idling Time
2.4.8.1 Engine Shutdown with Alternate Power Source during Hoteling
Class 8 heavy-duty diesel truck extended engine idling expends significant amounts of
fuel in the United States. Department of Transportation regulations require a certain amount of
rest for a corresponding period of driving hours, as discussed in Chapter 1. Extended idle occurs
when Class 8 long haul drivers rest in the sleeper cab compartment during rest periods as drivers
find it more convenient and economical to rest in the truck cab itself. In many cases it is the only
option available. During this rest period a driver will generally idle the truck in order to provide
heating or cooling or run on-board appliances. During rest periods the truck's main propulsion
engine is running but not engaged in gear and it remains in a stationary position. In some cases
the engine can idle in excess of 10 hours. During this period of time, fuel consumption will
generally average 0.8 gallons per hour.86 Average overnight fuel usage would exceed 8 gallons
in this example. When multiplied by the number of long haul trucks without idle control
technology that operate on national highways on a daily basis, the number of gallons consumed
by extended idling would exceed 3 million gallons per day. Fortunately, a number of
alternatives (idling reduction technologies) are available to alleviate this situation.
2.4.8.1.1 Idle Control Technologies
Idle reduction technologies in general utilize an alternative energy source in place of
operating the main engine. By using these devices the truck driver can obtain needed power for

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
services and appliances without running the engine. A number of these devices attach to the
truck providing heat, air conditioning, or electrical power for microwave ovens, televisions, etc.
The idle control technologies (along with their typical hourly fuel rate) available today
include the following:87
•	Auxiliary Power Unit (APU) powers the truck's heating, cooling, and electrical system.
The fuel use of an APU is typically 0.2 gallons per hour
•	Fuel Operated Heater (FOH) provides heating services to the truck through small diesel
fired heaters. The fuel use is typically 0.04 gallons per hour
•	Battery Air Conditioning Systems (B AC) provides cooling to the truck
•	Automatic Stop/Start Systems powers the truck systems through the battery and starts the
engine to recharge the battery after it reaches a threshold level.
•	Thermal Storage Systems provide cooling to trucks
Another alternative involves electrified parking spaces, with or without modification to
the truck. An electrified parking space system operates independently of the truck's engine and
allows the truck engine to be turned off while it supplies heating, cooling, and electrical power.
These systems provide off-board electrical power to operate either:
1.	A single system electrification which requires no on-board equipment by providing an
independent heating, cooling, and electrical power system, or
2.	A dual system which allows driver to plug in on-board equipment
In the first case, power is provided to stationary equipment that is temporarily attached to
the truck. In the second, the truck is modified to accept power from the electrical grid to operate
on-board truck equipment. The retail price of idle reduction systems varies depending on the
level of sophistication. For example, on-board technologies such as APUs can retail for over
$8,000 while options such as electrified parking spaces require negligible up-front costs for
equipment for the tractor itself, but will accrue fees with usage.88
CO2 emissions and fuel consumption during extended idling are significant contributors
to emissions and fuel consumption from Class 8 sleeper cabs. The federal test procedure does
evaluate idle emissions and fuel consumption as part of the drive cycle and related emissions
measurement. However, long duration extended idle emissions and fuel consumption are not
fully represented during the prescribed test cycle. To address the fact that real-world fuel and
emissions savings can occur with idle reduction technologies that cannot be reflected on the test
cycle, the agencies adopted a GEM input for manufacturers who provide for idle control using an
automatic engine shutdown system (AESS) on the tractor.
The GEM input, calculated as shown in Table 2-5, recognizes the CO2 reductions and
fuel consumption savings attributed to idle control systems and allows vehicle manufacturers
flexibility in product design and performance capabilities. The agencies first determined the fuel
consumption of each idle reduction technology, as noted previously. Due to the range of fuel
consumption of APUs and the precision of the available test information, the agencies are

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
utilizing, as proposed, an APU fuel consumption of 0.2 gal/hr. Then the agencies determined a
split between idling hours using the main engine versus the idle reduction technology. For
example, the baseline idle emission rate was assumed to be determined by 100 percent main
engine idling. For APU and battery APU technologies with a tamper-proof AESS, the agencies
assumed that these technologies would be operating 100 percent of the idling time. For
automatic start/stop systems with a tamper-proof AESS, the agencies determined that the idling
power would come from the battery half of the idling time and the other half would require main
engine idling. For fuel operated heaters with a tamper-proof AESS, the agencies assumed that
800 of the idling hours would involve the use of the fuel operated heater and that the main engine
would idle for the other 1000 hours per year to supply cooling and other needs. For idle
reduction technologies with an adjustable AESS, the agencies discounted the number of hours
operated by the idle reduction technology by 20 percent to account for the fact that it is an
adjustable (non tamper-proof) system. For adjustable AESS without an additional idle reduction
technology, the agencies set the number of main engine operating hours at 25 percent of the total
idle time to also reflect that it is adjustable and that the agencies have less certainty in the
continued use of this in the real world.
MEMA commented that the agencies should assume 2,500 hours of idling per year. The
agencies reviewed this and other studies to quantify idling operation. The 2010 NAS study
assumes between 1,500 and 2,400 idling hours per year.89 Gaines uses 1,800 hours per year.90
Brodrick, et al. assumes 1,818 hours per year (6 hours per day for 303 days per year) based on an
Argonne study and Freightliner fleet customers.91 An EPA technical paper states between 1,500
and 2,400 hours per year.92 Kahn uses 1,830 hours as the baseline extended idle case.93 Based
on the literature, the agencies are finalizing as proposed the use of 1,800 hours per year as
reasonably reflecting the available range of information.
The agencies assumed the average Class 8 sleeper cab travels 125,000 miles per year
(500 miles per day and 250 days per year) and carries 19 tons of payload (the standardized
payload finalized for Class 8 tractors) to calculate the baseline running emissions. For each
technology combination, the sum of the running and idling emissions was calculated and the
percent reduction in CO2 emissions from the main engine idling scenario was calculated. These
percent reduction values are included in 40 CFR 1037.520.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-4 Idle CO2 Emissions per Year for Idle Reduction Technologies

Idle Fuel
Consumption
(gal/hour)
Idle C02
emissions per
hour
IRT Idle
Hours per
Year
Main Engine
Idle Hours per
Year
Idle CO2 Emission per
year (grams)
Baseline
0.8
8144

1800
14,659,200
Tamper-Proof AESS
0.3
3054
1800
0
5,497,200
Tamper-Proof AESS w/
Diesel APU
0.3
3054
1800
0
5,497,200
Tamper-Proof AESS w/
Battery APU
0.02
203.6
1800
0
366,480
Tamper-Proof AESS w/
Automatic Stop-Start
0
0
900
900
7,329,600
Tamper-Proof AESS w/
FOH Cold, Main Engine
Warm
0.04
407.2
800
1000
8,469,760
Adjustable AESS w/
Diesel APU
0.3
3054
1440
360
7,329,600
Adjustable AESS w/
Battery APU
0.02
203.6
1440
360
3,225,024
Adjustable AESS w/
Automatic Stop-Start
0
0
720
1080
8,795,520
Adjustable AESS w/ FOH
Cold, Main Engine Warm
0.04
407.2
640
1160
9,707,648
Adjustable AESS
programmed to 5 minutes
0.3
3054
450
1350
12,368,700

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-5 GEM Input for Idle Reduction Technologies

TYPICAL
G/TON-
MILE
MILES
PER
YEAR
PAYLOAD
(TONS)
GHG
EMISSIONS
DUE TO
RUNNING (g)
GHG
EMISSIONS
DUE TO
RUNNING PLUS
IDLE (g)
% RED.
FROM
BASELINE
Baseline
88
125000
19
209,000,000
223,659,200
0%
Tamper-Proof AESS
88
125000
19
209,000,000
214,497,200
4.1%
Tamper-Proof AESS w/
Diesel APU
88
125000
19
209,000,000
214,497,200
4.1%
Tamper-Proof AESS w/
Battery APU
88
125000
19
209,000,000
209,366,480
6.4%
Tamper-Proof AESS w/
Automatic Stop-Start
88
125000
19
209,000,000
216,329,600
3.3%
Tamper-Proof AESS w/
FOH Cold, Main Engine
Warm
88
125000
19
209,000,000
217,469,760
2.8%
Adjustable AESS w/ Diesel
APU
88
125000
19
209,000,000
216,329,600
3.3%
Adjustable AESS w/
Battery APU
88
125000
19
209,000,000
212,225,024
5.1%
Adjustable AESS w/
Automatic Stop-Start
88
125000
19
209,000,000
217,795,520
2.6%
Adjustable AESS w/ FOH
Cold, Main Engine Warm
88
125000
19
209,000,000
218,707,648
2.2%
Adjustable AESS
programmed to 5 minutes
88
125000
19
209,000,000
221,368,700
1.0%
2.4.8.2 Stop Start
For heavy-duty vehicles to apply engine stop-start technology without a reduction in
vehicle function, some additional vehicle technologies are needed. To some extent this could be
considered similar to a mild hybrid system, but it is not the same as the mild hybrid system
described for HD pickups and vans described below in Chapter 2.5. The agencies are projecting
the presence of a battery sufficient to offer electrified power steering, and some other electrified
accessories. Some systems may replace the conventional alternator with a belt or crank driven
starter/alternator and may add high voltage electrical accessories (which may include electric
power steering and an auxiliary automatic transmission pump). The limited electrical
requirements of these systems allow the use of lead-acid batteries or supercapacitors for energy
storage, or the use of a small lithium-ion battery pack.
The NACFE Idle Reduction Confidence report was written with long haul tractors in
mind; however the section on vehicle electrification discusses inverters and on-vehicle solar

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
energy capture, and offers some insights relevant to vocational vehicle electrification as it
pertains to stop-start systems.94 Inverters and beltless alternators can use DC power stored in
batteries to power on-board electrical devices and re-start engines. One example of a company
that supplies battery-inverter idle reduction systems for vocational vehicles is Vanner.95 There
are also systems available today that are designed to capture solar energy and store this energy
for distribution to electrified accessories and engine re-starting. One example of a company that
supplies on-vehicle solar energy capture for vocational vehicles is eNow.96
2.4.8.3 Neutral Idle
Automatic transmissions historically apply torque to an engine when in gear at zero speed
because of torque converter, such as when stopped at a traffic light. A neutral idle technology
can disengage transmission with torque converter, thus reducing power loss to a minimum.
2.4.9 Air Conditioning
2.4.9.1 Refrigerant Leakage
Hydrofluorocarbon (HFC) refrigerants, which are powerful GHG pollutants, can be
emitted to the atmosphere through component and system leaks during operation, during
maintenance and servicing, and with disposal at the end of the vehicle's life. The current widely-
used refrigerant - R134a, has a much higher global warming potential (GWP) than CO2,
therefore a small leakage of this refrigerant has a much greater global warming impact than a
similar amount of emissions of CO2 or other mobile source GHGs.
Direct emissions of HFC from air conditioning systems can be reduced by minimizing
system leaks. Based on measurements from 300 European light-duty vehicles (collected in 2002
and 2003), Schwarz and Harnisch estimate that the average HFC direct leakage rate from modern
A/C systems was estimated to be 53 g/yr.97 This corresponds to a leakage rate of 6.9 percent per
year. This was estimated by extracting the refrigerant from recruited vehicles and comparing the
amount extracted to the amount originally filled (as per the vehicle specifications). The fleet and
size of vehicles differs from Europe and the United States, therefore it is conceivable that
vehicles in the United States could have a different leakage rate. The authors measured the
average charge of refrigerant at initial fill to be about 747 grams (it is somewhat higher in the
U.S. at 770g), and that the smaller cars (684 gram charge) emitted less than the higher charge
vehicles (883 gram charge). Moreover, due to the climate differences, the A/C usage patterns
also vary between the two continents, which may influence leakage rates.
Vincent et al., from the California Air Resources Board estimated the in-use refrigerant
leakage rate to be 80 g/yr.98 This is based on consumption of refrigerant in commercial fleets,
surveys of vehicle owners and technicians. The study assumed an average A/C charge size of
950 grams and a recharge rate of 1 in 16 years (lifetime). The recharges occurred when the
system was 52 percent empty and the fraction recovered at end-of-life was 8.5 percent.
Manufacturers today are complying with the HD Phase 1 program requirements to reduce
A/C leakage emissions by utilizing high-quality, low-leakage air conditioning system
components in the production of new tractors, and HD pickup trucks and vans. Some of the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
components available to manufacturers are low-permeation flexible hoses, multiple o-ring or seal
washer connections, and multiple-lip compressor shaft seals. The availability of low leakage
components in the market is being driven by the air conditioning credit program in the light-duty
GHG rulemaking. The cooperative industry and government Improved Mobile Air Conditioning
(IMAC) program has demonstrated that new-vehicle leakage emissions can be reduced by 50
percent by reducing the number and improving the quality of the components, fittings, seals, and
hoses of the AJC system."
2.4.9.2	System Efficiency
CO2 emissions and fuel consumption are also associated with air conditioner efficiency,
since air conditioners create load on the engine. See 74 FR at 49529. The agencies are adopting
Phase 2 provisions for tractors and vocational vehicles recognizing the opportunity for more
efficient air conditioning systems.
2.4.9.3	Solar Control
Solar control glazing consists of both solar absorbing and solar reflective glazing that can
reduce the temperature inside a vehicle, and therefore reduce the air conditioning requirements.
The reduction in air conditioning load can lead to reductions in fuel consumption and GHG
emissions. CARB's Low Emission Vehicle III Regulations (LEVIII) include a GHG credit for
this technology.100 The Enhanced Protective Glass Automotive Association indicated that new
heavy-duty trucks today typically use solar absorbing glass.
Solar reflective paints reflect approximately a half of the solar energy by reflecting the
infrared portion of the solar spectrum. A study conducted by National Renewable Energy
Laboratory found benefits to sleeper cab tractors using reflective paint and other thermal control
technologies.101
There are many factors that influence the level of emissions and fuel consumption
reductions due to solar control glazing and solar reflective paint. The fraction of time spent
idling during the daytime hours, the fraction of hours of the day that are sunny, the ambient
temperatures, the wind conditions and/or vehicle speed, the fraction of the vehicles that are
painted colors other than white, and other factors influence the potential impact of these
technologies. Because of the difficulty in assessing the potential emission reductions from solar
control paint and glazing, the agencies did not propose this technology as part of HD Phase 2.
The agencies received some clarifications from ARB on our evaluation of solar technologies and
some CBI from Daimler, but not a sufficient amount of information to evaluate the baseline level
of solar control that exists in the heavy-duty market today, determine the effectiveness of each of
the solar technologies, or to develop a definition of what qualifies as a solar control technology
that could be used in the regulations. Therefore, the agencies would consider solar control to be
a technology that manufacturers may consider pursuing through the off-cycle credit program.
2.4.10 Other Accessory Improvements
Electric power steering (EPS) provides a potential reduction in CO2 emissions and fuel
consumption over hydraulic power steering because of reduced overall accessory loads. This

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
eliminates the parasitic losses associated with belt-driven power steering pumps which
consistently draw load from the engine to pump hydraulic fluid through the steering actuation
systems even when the wheels are not being turned. EPS is an enabler for all vehicle
hybridization technologies since it provides power steering when the engine is off. EPS may be
implemented on most vehicles with a standard 12V system. Some heavier vehicles such as Class
2b and 3 may require a higher voltage system which may add cost and complexity.
The 2017 light-duty final rule estimated a one to two percent effectiveness based on the
2002 NAS report, a Sierra Research report, and confidential manufacturer data. The SwRI report
estimated 0.8 percent to 1 percent effectiveness. The agencies reviewed these SwRI
effectiveness estimates and found them to be accurate, thus they have been retained for this rule.
In addition to the purely hybrid technologies, which decreases the proportion of
propulsion energy coming from the fuel by increasing the proportion of that energy coming from
electricity, there are other steps that can be taken to improve the efficiency of auxiliary functions
(e.g., power-assisted steering or air-conditioning) which also reduce CO2emissions and fuel
consumption. Optimization of the auxiliary functions is collectively referred to as vehicle or
accessory load electrification because they generally use electricity instead of engine power.
These improvements are considered enablers for hybrid systems.
2.4.11 Predictive Cruise Control
Cruise control is commonly used in light-duty and heavy-duty applications to maintain a
vehicle at a set speed. However, cruise control systems with additional intelligence and
predictive control are much more complex but offer opportunities to reduce fuel consumption
and GHG emissions. Many of the heavy-duty manufacturers are developing intelligent cruise
control systems and though they resemble each other in overall function, each manufacturer is
doing it differently.
As an example, an intelligent cruise control system partnered with a source of elevation
information could detect when the vehicle is on a hill and know when it is close to cresting the
hill. During this time, the vehicle may be allowed to temporarily travel at a lower speed to
prevent the need for a transmission downshift, which consumes more fuel because it requires the
engine to increase the rpm and run in a less efficient part of the fuel map. Similarly, predictive
cruise control allows a vehicle to exceed the speed set point by a specified amount so that the
vehicle will start the next hill at a higher speed and reduce the likelihood of needing to downshift
on the next hill.
The amount of reduction in fuel consumption and CO2 emissions depends significantly on the
terrain. Sources estimate that the overall savings is approximately two percent.102
2.5 Technology Application- HD Pickups and Vans
2.5.1 Gasoline Engines
Spark ignited (gasoline) engines used in complete Class 2b and 3 pickups and vans
include engines offered in a manufacturer's light-duty truck counterparts, as well as engines

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
specific to the Class 2b and 3 segment. Based on 2014 MY specifications, these engines
typically range in displacement between 5 and 7 liters, though smaller and larger engines have
also been used in this market. The majority of these engines are a V8 configuration, although the
VI0 configuration is also marketed.
The engine technologies are based on the technologies described in the Light-Duty
Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards
Joint Technical Support Document and in Chapter 2. 3 above.103 (Note, however, that because
this section deals specifically with application to 2b/3 vehicles, the projected effectiveness may
vary from that presented in the generic discussions presented earlier). Some of the references
come from the 2010 NAS Report, Technologies and Approaches to Reducing the Fuel
Consumption of Medium and Heavy-Duty Vehicles. These technologies include engine friction
reduction, cam phasing, cylinder deactivation and stoichiometric gas direct injection. Included
with each technology description is an estimate of the improvement in fuel consumption and
GHGs that is achievable through the use of the technology in heavy-duty pickup trucks and vans
over their applicable operation and test cycles.
The technology effectiveness values are generally described as ranges that represent
expected levels of effectiveness with appropriate implementation of the technology but actual
effectiveness levels will vary with manufacturer-specific design, and with specifications for the
technologies. These may include considerations for durability or other related constraints. The
agencies did not receive comments disputing the expected technology effectiveness values
reported in the NPRM and draft RIA.
2.5.1.1 Low Friction Lubricants
One of the most basic methods of reducing fuel consumption in both gasoline and diesel
engines is the use of lower viscosity engine lubricants. More advanced multi-viscosity engine
oils are available today with improved performance in a wider temperature band and with better
lubricating properties. This can be accomplished by changes to the oil base stock (e.g.,
switching engine lubricants from a Group I base oils to lower-friction, lower viscosity Group III
synthetic) and through changes to lubricant additive packages (e.g., friction modifiers and
viscosity improvers). The use of 5W-30 motor oil is now widespread and auto manufacturers are
introducing the use of even lower viscosity oils, such as 5W-20 and 0W-20, to improve cold-
flow properties and reduce cold start friction. However, in some cases, changes to the
crankshaft, rod and main bearings and changes to the mechanical tolerances of engine
components may be required. In all cases, durability testing would be required to ensure that
durability is not compromised. The shift to lower viscosity and lower friction lubricants would
also improve the effectiveness of valvetrain technologies such as cylinder deactivation, which
rely on a minimum oil temperature (viscosity) for operation.
Based on light-duty 2017-2025 MY vehicle rulemaking, and previously-received
confidential manufacturer data, the agencies have estimated the effectiveness of low friction
lubricants to be between 0 to 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.5.1.2	Engine Friction Reduction
Manufacturers can reduce friction and improve fuel consumption by improving the
design of engine components and subsystems. Approximately 10 percent of the energy
consumed by a vehicle is lost to friction, and just over half is due to frictional losses within the
engine. Examples include improvements in low-tension piston rings, piston skirt design, roller
cam followers, improved crankshaft design and bearings, material coatings, material substitution,
more optimal thermal management, and piston and cylinder surface treatments. Additionally, as
computer-aided modeling software continues to improve, more opportunities for evolutionary
friction reductions may become available.
Estimations of fuel consumption improvements due to reduced engine friction from the
2015 NHTSA Technology Study range from 1 percent to 3 percent. The agencies believe that
this range is accurate.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.3	Engine Parasitic Demand Reduction
Manufacturers can reduce mechanical engine loads and improve fuel consumption by
implementing variable-displacement oil pumps, higher-efficiency direct injection fuel pumps,
and variable speed/displacement coolant pumps.
Estimations of fuel consumption improvements due to reduced engine parasitic demand
from the 2015 NHTSA Technology Study range from 1 percent to 2 percent. The agencies
believe that this range is accurate.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.4	Variable Valve Timing
Variable valve timing (VVT) classifies a family of valve-train designs that alter the
timing of the intake valve, exhaust valve, or both, primarily to reduce pumping losses, increase
specific power, and control the level of residual gases in the cylinder. VVT reduces pumping
losses when the engine is lightly loaded by controlling valve timing closer to the optimum
needed to sustain horsepower and torque. VVT can also improve volumetric efficiency at higher
engine speeds and loads. Additionally, VVT can be used to alter (and optimize) the effective
compression ratio where it is advantageous for certain engine operating modes (e.g., in the
Atkinson Cycle).
VVT has now become a widely adopted technology in the light duty fleet: in MY 2014,
most of all new cars and light trucks had engines with some method of variable valve timing.104
Manufacturers are currently using many different types of variable valve timing, which have a
variety of different names and methods. Therefore, the degree of further improvement across the
fleet is limited by the level of valvetrain technology already implemented on the vehicles. The
three major types of VVT are listed below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Each of the implementations of VVT uses a cam phaser to adjust the camshaft angular
position relative to the crankshaft position, referred to as "camshaft phasing." The phase
adjustment results in changes to the pumping work required by the engine to accomplish the gas
exchange process. The majority of current cam phaser applications use hydraulically-actuated
units, powered by engine oil pressure and managed by a solenoid that controls the oil pressure
supplied to the phaser.
2.5.1.4.1	Coupled Cam Phasing for Overhead Valve (OHV) and Single
Overhead Camshaft (SOHC) Engines
Valvetrains with coupled (or coordinated) cam phasing (CCP) can modify the timing of
both the inlet valves and the exhaust valves an equal amount by varying the phasing of the
camshaft across an engine's range of operating speeds; also known as VVT. For engines
configured as an overhead valve (OHV) or as a single overhead camshaft (SOHC) only one cam
phaser is required per camshaft to achieve CCP.
Based on the heavy-duty 2014-2018 MY vehicle rulemaking, 2015 NHTSA Technology
Study, and previously-received confidential manufacturer data, the agencies estimate the fuel
consumption reduction effectiveness of this technology to be between 1 and 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.4.2	Intake Cam Phasing (ICP) for Dual Overhead Camshaft Engines
(DOHC)
Valvetrains with ICP, which is the simplest of the cam phasing technologies, can modify
the timing of the inlet valves by phasing the intake camshaft while the exhaust valve timing
remains fixed. This requires the addition of a cam phaser on each bank of intake valves on the
engine. An in-line 4-cylinder engine has one bank of intake valves, while V-configured engines
have two banks of intake valves.
Some newer Class 2b and 3 market entries are offering dual overhead camshaft (DOHC)
engine designs where two camshafts are used to operate the intake and exhaust valves
independently. Consistent with the heavy-duty 2014-2018 MY vehicle rulemaking and the SwRI
report, the agencies agree with the effectiveness values of 1 to 2 percent reduction in fuel
consumption for this technology.
2.5.1.4.3	Dual Cam Phasing (DCP) for Dual Overhead Camshaft Engines
(DOHC)
The most flexible VVT design is dual (independent) cam phasing, where the intake and
exhaust valve opening and closing events are controlled independently. This option allows the
option of controlling valve overlap, which can be used as an internal EGR strategy. At low
engine loads, DCP creates a reduction in pumping losses, resulting in improved fuel
consumption. Increased internal EGR also results in lower engine-out NOx emissions. The
amount by which fuel consumption is improved depends on the residual tolerance of the
combustion system. Additional improvements are observed at idle, where low valve overlap

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
could result in improved combustion stability, potentially reducing idle fuel consumption. DCP
requires two cam phasers on each bank of the engine.
Some newer Class 2b and 3 market entries are offering dual overhead camshaft (DOHC)
engine designs where two camshafts are used to operate the intake and exhaust valves
independently. Consistent with the light-duty 2012-2016 MY vehicle rulemaking and the SwRI
report, the agencies agree with the effectiveness values of 1 to 3 percent reduction in fuel
consumption for this technology.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.5 Variable Valve Lift (VVL)
Controlling the lift of the valves provides a potential for further efficiency improvements.
By optimizing the valve-lift profile for specific engine operating regions, the pumping losses can
be reduced by reducing the amount of throttling required to produce the desired engine power
output. By moving the throttling losses further downstream of the throttle valve, the heat
transfer losses that occur from the throttling process are directed into the fresh charge-air mixture
just prior to compression, delaying the onset of knock-limited combustion processes. Variable
valve lift control can also be used to induce in-cylinder mixture motion, which improves fuel-air
mixing and can result in improved thermodynamic efficiency. Variable valve lift control can
also potentially reduce overall valvetrain friction. At the same time, such systems may also incur
increased parasitic losses associated with their actuation mechanisms. A number of
manufacturers have already implemented VVL into their fleets (Toyota, Honda, and BMW).
There are two major classifications of variable valve lift, described below:
2.5.1.5.1 Discrete Variable Valve Lift (DWL)
Discrete variable valve lift (DVVL) systems allow the selection between two or three
discrete cam profiles by means of a hydraulically-actuated mechanical system. By optimizing
the cam profile for specific engine operating regions, the pumping losses can be reduced by
reducing the amount of throttling required to produce the desired engine power output. This
increases the efficiency of the engine. These cam profiles consist of a low and a high-lift lobe,
and may include an inert or blank lobe to incorporate cylinder deactivation (in the case of a 3-
step DVVL system). DVVL is normally applied together with VVT control. DVVL is also
known as Cam Profile Switching (CPS). DVVL is a mature technology with low technical risk.
Based on the light-duty MY 2017-2025 final rule, previously-received confidential
manufacturer data, 2015 NHTSA Technology Study, and report from the Northeast States Center
for a Clean Air Future (NESCCAF), the agencies estimate the fuel consumption reduction
effectiveness of this technology to be between 1 and 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.5.1.6	Cylinder Deactivation
In conventional spark-ignited engines throttling the airflow controls engine torque output.
At partial loads, efficiency can be improved by using cylinder deactivation instead of throttling.
Cylinder deactivation can improve engine efficiency by disabling or deactivating (usually) half
of the cylinders when the load is less than half of the engine's total torque capability - the valves
are kept closed, and no fuel is injected - as a result, the trapped air within the deactivated
cylinders is simply compressed and expanded as an air spring, with reduced friction and heat
losses. The active cylinders combust at almost double the load required if all of the cylinders
were operating. Pumping losses are significantly reduced as long as the engine is operated in
this "part-cylinder" mode.
Cylinder deactivation control strategy relies on setting maximum manifold absolute
pressures or predicted torque within which it can deactivate the cylinders. Noise and vibration
issues reduce the operating range to which cylinder deactivation is allowed, although
manufacturers are exploring vehicle changes that enable increasing the amount of time that
cylinder deactivation might be suitable. Some manufacturers may choose to adopt active engine
mounts and/or active noise cancellations systems to address Noise Vibration and Harshness
(NVH) concerns and to allow a greater operating range of activation.
Effectiveness improvements scale roughly with engine displacement-to-vehicle weight
ratio: the higher displacement-to-weight vehicles, operating at lower relative loads for normal
driving, have the potential to operate in part-cylinder mode more frequently.
Based on the 2015 NHTSA Technology Study and previously-received confidential
manufacturer data, the agencies estimate the fuel consumption reduction effectiveness of this
technology to be between 0 and 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.7	Stoichiometric Gasoline Direct Injection
Stoichiometric gasoline direct injection (SGDI) engines inject fuel at high pressure
directly into the combustion chamber (rather than the intake port in port fuel injection). SGDI
requires changes to the injector design, an additional high pressure fuel pump, new fuel rails to
handle the higher fuel pressures, and changes to the cylinder head and piston crown design.
Direct injection of the fuel into the cylinder improves cooling of the air/fuel charge within the
cylinder, which allows for higher compression ratios and increased thermodynamic efficiency
without the onset of combustion knock. Recent injector design advances, improved electronic
engine management systems and the introduction of multiple injection events per cylinder firing
cycle promote better mixing of the air and fuel, enhance combustion rates, increase residual
exhaust gas tolerance and improve cold start emissions. SGDI engines achieve higher power
density and match well with other technologies, such as boosting and variable valvetrain designs.
Several manufacturers have recently introduced vehicles with SGDI engines, including
GM and Ford, who have announced their plans to increase dramatically the number of SGDI
engines in their light-duty portfolios.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Based on the heavy-duty 2014-2018 MY vehicle rulemaking, 2015 NHTSA Technology
Study, and previously-received confidential manufacturer data, the agencies estimate the fuel
consumption reduction effectiveness of SGDI to be between 1 and 2 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.1.8 Turbocharging and Downsizing (TRBDS)
The specific power of a naturally aspirated engine is primarily limited by the rate at
which the engine is able to draw air into the combustion chambers. Turbocharging and
supercharging (grouped together here as boosting) are two methods to increase the intake
manifold pressure and cylinder charge-air mass above naturally aspirated levels. Boosting
increases the airflow into the engine, thus increasing the specific power level, and with it the
ability to reduce engine displacement while maintaining performance. This effectively reduces
the pumping losses at lighter loads in comparison to a larger, naturally aspirated engine.
Almost every major manufacturer currently markets a vehicle with some form of
boosting. While boosting has been a common practice for increasing performance for several
decades, turbocharging has considerable potential to improve fuel economy and reduce CO2
emissions when the engine displacement is also reduced. Specific power levels for a boosted
engine often exceed 100 hp/L, compared to average naturally aspirated engine power densities of
roughly 70 hp/L. As a result, engines can be downsized roughly 30 percent or higher while
maintaining similar peak output levels. In the last decade, improvements to turbocharger turbine
and compressor design have improved their reliability and performance across the entire engine
operating range. New variable geometry turbines and ball-bearing center cartridges allow faster
turbocharger spool-up (virtually eliminating the once-common "turbo lag") while maintaining
high flow rates for increased boost at high engine speeds. Low speed torque output has been
dramatically improved for modern turbocharged engines. However, even with turbocharger
improvements, maximum engine torque at very low engine speed conditions, for example launch
from standstill, is increased less than at mid and high engine speed conditions. The potential to
downsize engines may be less on vehicles with low displacement to vehicle mass ratios for
example a very small displacement engine in a vehicle with significant curb weight, in order to
provide adequate acceleration from standstill, particularly up grades or at high altitudes.
Use of GDI systems with turbocharged engines and charge air cooling also reduces the
fuel octane requirements for knock limited combustion and allows the use of higher compression
ratios. Ford's "EcoBoost" downsized, turbocharged GDI engines introduced on MY 2010
vehicles allow the replacement of V8 engines with V6 engines with improved in 0-60 mph
acceleration and with fuel economy improvements of up to 12 percent.105
Recently published data with advanced spray-guided injection systems and more
aggressive engine downsizing targeted towards reduced fuel consumption and CO2 emissions
reductions indicate that the potential for reducing CO2 emissions for turbocharged, downsized
GDI engines may be as much as 15 to 30 percent relative to port-fuel-injected engines.14'15'16'17'18
Confidential manufacturer data suggests an incremental range of fuel consumption and CO2
emission reduction of 4.8 to 7.5 percent for turbocharging and downsizing. Other publicly-
available sources suggest a fuel consumption and CO2 emission reduction of 8 to 13 percent

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
compared to current-production naturally-aspirated engines without friction reduction or other
fuel economy technologies: a joint technical paper by Bosch and Ricardo suggesting fuel
economy gain of 8 to 10 percent for downsizing from a 5.7 liter port injection V8 to a 3.6 liter
V6 with direct injection using a wall-guided direct injection system;106 a Renault report
suggesting a 11.9 percent NEDC fuel consumption gain for downsizing from a 1.4 liter port
injection in-line 4-cylinder engine to a 1.0 liter in-line 4-cylinder engine, also with wall-guided
direct injection;107 and a Robert Bosch paper suggesting a 13 percent NEDC gain for downsizing
to a turbocharged DI engine, again with wall-guided injection.108 These reported fuel economy
benefits show a wide range depending on the SGDI technology employed.
The agencies reviewed estimates from the LD 2017-2025 final rule, the TSD, and
existing public literature. The previous estimate from the MYs 2017-2025 suggested a 12 to 14
percent effectiveness improvement, which included low friction lubricant (level one), engine
friction reduction (level one), DCP, DVVL and SGDI, over baseline fixed-valve engines, similar
to the estimate for Ford's EcoBoost engine, which is already in production. Additionally, the
agencies analyzed Ricardo vehicle simulation data and the 2015 NHTSA Technology Study for
various turbocharged engine packages. Based on these data, and considering the widespread
nature of the public estimates, the agencies assume that turbocharging and downsizing, would
provide a 16.4 percent effectiveness improvement over naturally aspirated engines as applied to
Class 2b and 3 vehicles.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
Note that for this analysis we determined that this technology path is only applicable to
heavy duty applications that have operating conditions more closely associated with light duty
vehicles. This includes vans designed mainly for cargo volume or modest payloads having
similar GCWR to light duty applications. These vans cannot tow trailers heavier than similar
light duty vehicles and are largely already sharing engines of significantly smaller displacement
and cylinder count compared to heavy duty vehicles designed mainly for trailer towing.
2.5.1.9 Cooled Exhaust-Gas Recirculation
Cooled exhaust gas recirculation or Boosted EGR is a combustion concept that involves
utilizing EGR as a charge diluent for controlling combustion temperatures and cooling the EGR
prior to its introduction to the combustion system. Higher exhaust gas residual levels at part load
conditions reduce pumping losses for increased fuel economy. The additional charge dilution
enabled by cooled EGR reduces the incidence of knocking combustion and obviates the need for
fuel enrichment at high engine power. This allows for higher boost pressure and/or compression
ratio and further reduction in engine displacement and both pumping and friction losses while
maintaining performance. Engines of this type use GDI and both dual cam phasing and discrete
variable valve lift. The EGR systems considered in this rule would use a dual-loop system with
both high and low pressure EGR loops and dual EGR coolers. The engines would also use
single-stage, variable geometry turbocharging with higher intake boost pressure available across
a broader range of engine operation than conventional turbocharged SI engines. Such a system is
estimated to be capable of an additional 3 to 5 percent effectiveness relative to a turbocharged,
downsized GDI engine without cooled-EGR. The agencies have also considered a more

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
advanced version of such a cooled EGR system that employs very high combustion pressures by
using dual stage turbocharging.
2.5.2 Diesel Engines
Diesel engines in this class of vehicle have emission characteristics that present
challenges to meeting federal NOx emissions standards. It is a significant systems-engineering
challenge to maintain the fuel consumption advantage of the diesel engine while meeting U.S.
emissions regulations. Fuel consumption can be negatively impacted by emissions reduction
strategies depending on the combination of strategies employed. Emission compliance strategies
for diesel vehicles sold in the U.S. are expected to include a combination of improvements of
combustion, air handling system, aftertreatment, and advanced system control optimization.
These emission control strategies are being introduced on Tier 2 light-duty diesel vehicles today.
Some of the engine technologies are described in the Light-Duty Vehicle Greenhouse
Gas Emission Standards and Corporate Average Fuel Economy Standards Joint Technical
Support Document.109 Others are from the 2010 NAS Report, Technologies and Approaches to
Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles, and the 2015 NHTSA
Technology Study. Several key advances in diesel technology have made it possible to reduce
emissions coming from the engine prior to aftertreatment. These technologies include engine
friction and parasitic loss reduction, improved fuel systems (higher injection pressure and
multiple-injection capability), advanced controls and sensors to optimize combustion and
emissions performance, higher EGR levels and EGR cooling to reduce NOx, and advanced
turbocharging systems.
2.5.2.1	Low Friction Lubricants
Consistent with the discussion above for gasoline engines (see Chapter 2.5.1), the
agencies are expecting some engine changes to accommodate low friction lubricants. Based on
the light-duty 2014-2018 MY HD vehicle rulemaking, and previously-received confidential
manufacturer data, the agencies estimated the effectiveness of low friction lubricants to be
between 0 and 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
Based on a survey of the current powertrains being applied to the Class 2b and 3 segment
and the level of powertrain sharing with the light duty vehicle market for these vehicles, the
majority of light heavy duty gasoline engines in the 2014 Class 2b and 3 vehicle models are
utilizing some form of low friction lubricants to achieve power and emission goals, and so this
technology is considered to be in the baseline.
2.5.2.2	Engine Friction Reduction
Reduced friction in bearings, valve trains, and the piston-to-liner interface will improve
efficiency. Friction reduction opportunities in the engine valve train and at its roller/tappet
interfaces exist for several production engines. In virtually all production engines, the piston at
its skirt/cylinder wall interface, wrist pin and oil ring/cylinder wall interface offer opportunities

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
for friction reduction. Use of more advanced oil lubricant that could be available for production
in the future may also eventually play a key role in reducing friction. Mechanical loads can also
be reduced by converting the water, oil, and fuel pumps in the engine from fixed displacement to
variable displacement.
Estimations of fuel consumption improvements due to reduced engine friction from the
2015 NHTSA Technology Study range from 1 percent to 2 percent. The agencies believe that
this range is accurate.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.2.3	Turbocharger Technology
Compact two stage turbochargers can increase the boost level with wider operation range,
thus improving engine thermal efficiency. Ford's new developed 6.7L Scorpion engine features
a twin-compressor turbocharger110. Cummins has also developed its own two stage
turbochargers.111 It is expected that this type of technology will continue to be improved by
better system matching and development of higher compressor and turbine efficiency.
Based on the 2015 NHTSA Technology Study and previously-received confidential
manufacturer data, the agencies estimate the fuel consumption reduction effectiveness of this
technology to be between 2 and 3 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.2.4	Reduction of Parasitic Loads
Accessories that are traditionally gear- or belt-driven by a vehicle's engine can be
optimized and/or converted to electric power. Examples include the engine water pump, oil
pump, fuel injection pump, air compressor, power-steering pump, cooling fans, and the vehicle's
air-conditioning system which can be converted to full electrically driven loads or an electro-
mechanical arrangement that retains some mechanically connected aspects. Optimization and
improved pressure regulation may significantly reduce the parasitic load of the water, air and
fuel pumps. Electrification may result in a reduction in power demand, because electrically-
powered accessories (such as the air compressor or power steering) operate only when needed if
they are electrically powered, but they impose a parasitic demand all the time if they are engine-
driven. In other cases, such as cooling fans or an engine's water pump, electric power allows the
accessory to run at speeds independent of engine speed, which can reduce power consumption.
The 2015 NHTSA Technology Study used a 1 to 2 percent fuel consumption reduction for diesel
engine parasitic improvements.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.2.5	Aftertreatment Improvements
The HD diesel pickup and van segment has largely adopted the SCR type of
aftertreatment system to comply with criteria pollutant emission standards. As the experience
base for SCR expands over the next few years, many improvements in this aftertreatment system

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
such as construction of the catalyst, thermal management, and reductant optimization may result
in a reduction in the amount of fuel consumed by the engine via combustion optimization, taking
advantage of the SCR's capability to reduce higher levels of NOx emitted by the engine.
However, due to uncertainties with these improvements regarding the extent of current
optimization and future criteria emissions obligations, the agencies are not considering
aftertreatment improvements as a fuel-saving technology in the rulemaking analysis for HD
pickups and vans.
2.5.3 Drivetrain
The agencies have also reviewed the transmission technology estimates used in the light-
duty 2012-2016 MY vehicle rulemaking. In doing so, the agencies have considered or
reconsidered all available sources and updated the estimates as appropriate. The section below
describes each of the transmission technologies considered for this rulemaking.
2.5.3.1	Automatic 8-Speed Transmissions
Manufacturers can also choose to replace 6-speed transmissions with transmissions
capable of 8-speeds or more. Additional ratios allow for further optimization of engine operation
over a wider range of conditions, but this is subject to diminishing returns as the number of
speeds increases. As additional gear sets are added (which may be necessary in some cases to
achieve the higher number of ratios), additional weight and friction are introduced. Also, the
additional shifting of such a transmission can be perceived as bothersome to some consumers, so
manufacturers continue to develop strategies for smooth operation.
As discussed in the heavy-duty 2014-2018 MY vehicle rulemaking, taking into account
confidential manufacturer data, we projected that 8-speed transmissions could incrementally
reduce fuel consumption by 1 to 3 percent from a baseline 6-speed automatic transmission. The
SwRI report uses 2 to 3 percent fuel consumption reduction when replacing 6-speed baseline
automatic transmissions with improved 8-speed automatic transmissions.
The agencies reviewed and revised these effectiveness estimates based on usage and
testing methods for Class 2b and 3 vehicles. The agencies estimate the effectiveness for a
conversion from a 6 to 8-speed transmission to be 2.7 percent.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.3.2	High Efficiency Transmission
For this rule, a high efficiency transmission refers to some or all of a suite of incremental
transmission improvement technologies that should be available within the 2019 to 2025
timeframe. The majority of these improvements address mechanical friction within the
transmission. These improvements include but are not limited to: shifting clutch technology
improvements, improved kinematic design, dry sump lubrication systems, more efficient seals,
bearings and clutches (reducing drag), component superfinishing and improved transmission
lubricants.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.5.3.3	Electric Power Steering (EPS)
Electric power steering (EPS) provides a potential reduction in CO2 emissions and fuel
consumption over hydraulic power steering because of reduced overall accessory loads. This
eliminates the parasitic losses associated with belt-driven power steering pumps which
consistently draw load from the engine to pump hydraulic fluid through the steering actuation
systems even when the wheels are not being turned. EPS is an enabler for all vehicle
hybridization technologies since it provides power steering when the engine is off. EPS may be
implemented on most vehicles with a standard 12V system. Some heavier vehicles such as Class
2b and 3 may require a higher voltage system which may add cost and complexity.
The 2017 light-duty final rule estimated a 1 to 2 percent effectiveness based on the 2002
NAS report, a Sierra Research report, and confidential manufacturer data. The SwRI report
estimated 0.8 percent to 1 percent effectiveness. The agencies reviewed these SwRI
effectiveness estimates and found them to be accurate, thus they have been retained for this rule.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.3.4	Improved Accessories
The accessories on an engine, including the alternator, coolant and oil pumps are
traditionally mechanically-driven. A reduction in CO2 emissions and fuel consumption can be
realized by driving them electrically, and only when needed ("on-demand").
Electric water pumps and electric fans can provide better control of engine cooling. For
example, coolant flow from an electric water pump can be reduced and the radiator fan can be
shut off during engine warm-up or cold ambient temperature conditions which would reduce
warm-up time, reduce warm-up fuel enrichment, and reduce parasitic losses.
Indirect benefit may be obtained by reducing the flow from the water pump electrically
during the engine warm-up period, allowing the engine to heat more rapidly and thereby
reducing the fuel enrichment needed during cold operation and warm-up of the engine. Faster oil
warm-up may also result from better management of the coolant warm-up period. Further
benefit may be obtained when electrification is combined with an improved, higher efficiency
engine alternator used to supply power to the electrified accessories.
Intelligent cooling can more easily be applied to vehicles that do not typically carry
heavy payloads, so larger vehicles with towing capacity present a challenge, as these vehicles
have high cooling fan loads.A However, towing vehicles tend to have large cooling system
capacity and flow scaled to required heat rejection levels when under full load situations such as
towing at GCWR in extreme ambient conditions. During almost all other situations, this design
characteristic may result in unnecessary energy usage for coolant pumping and heat rejection to
the radiator.
A In the CAFE model, improved accessories refers solely to improved engine cooling. However, EPA has included
a high efficiency alternator in this category, as well as improvements to the cooling system.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The agencies considered whether to include electric oil pump technology for the
rulemaking. Because it is necessary to operate the oil pump any time the engine is running,
electric oil pump technology has insignificant effect on efficiency. Therefore, the agencies
decided to not include electric oil pump technology.
2.5.3.5	Mild Hybrid (MHEV)
Mild hybrid systems offer idle-stop functionality and a limited level of regenerative
braking and power assist. These systems replace the conventional alternator with a belt or crank
driven starter/alternator and may add high voltage electrical accessories (which may include
electric power steering and an auxiliary automatic transmission pump). The limited electrical
requirements of these systems allow the use of lead-acid batteries or supercapacitors for energy
storage, or the use of a small lithium-ion battery pack.
For the MHEV technology the agencies sized the system using a 7 kW starter/generator
and 8 kWh Li-ion battery pack. The estimates were developed by Argonne National Laboratory
as a supplement to the 2015 NHTSA Technology Study, resulting in an effectiveness range of 4
to 5 percent depending on the vehicle's engine.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.3.6	Strong Hybrid (SHEV)
A hybrid vehicle is a vehicle that combines two significant sources of propulsion energy,
where one uses a consumable fuel (like gasoline), and one is rechargeable (during operation, or
by another energy source). Hybrid technology is well established in the U.S. market and more
manufacturers are adding hybrid models to their lineups. Hybrids reduce fuel consumption
through three major mechanisms:
•	The internal combustion engine can be optimized (through downsizing, modifying the
operating cycle, or other control techniques) to operate at or near its most efficient
point more of the time. Power loss from engine downsizing can be mitigated by
employing power assist from the secondary power source.
•	Some of the energy normally lost as heat while braking can be captured and stored in
the energy storage system for later use.
•	The engine is turned off when it is not needed, such as when the vehicle is coasting or
when stopped.
Hybrid vehicles utilize some combination of the three above mechanisms to reduce fuel
consumption and CO2 emissions. The effectiveness of fuel consumption and CO2 reduction
depends on the utilization of the above mechanisms and how aggressively they are pursued. One
area where this variation is particularly prevalent is in the choice of engine size and its effect on
balancing fuel economy and performance. Some manufacturers choose not to downsize the
engine when applying hybrid technologies. In these cases, performance is vastly improved,
while fuel efficiency improves significantly less than if the engine was downsized to maintain

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
the same performance as the conventional version. The non-downsizing approach is used for
vehicles like trucks where towing and/or hauling are an integral part of their performance
requirements. In these cases, if the engine is downsized, the battery can be quickly drained
during a long hill climb with a heavy load, leaving only a downsized engine to carry the entire
load. Because towing capability is currently a heavily-marketed truck attribute, manufacturers
are hesitant to offer a truck with downsized engine which can lead to a significantly diminished
towing performance when the battery state of charge level is low, and therefore engines are
traditionally not downsized for these vehicles. As noted above, in assessing costs of this
technology, the agencies assumed in all instances that the engine would not be downsized.
Strong Hybrid technology utilizes an axial electric motor connected to the transmission
input shaft and connected to the engine crankshaft through a clutch. The axial motor is a
motor/generator that can provide sufficient torque for launch assist, all electric operation, and the
ability to recover significant levels of braking energy.
For SHEV, the agencies also relied on the study by Argonne National Laboratory to
supplement the 2015 NHTSA Technology Study to determine that the effectiveness of these
systems in terms of CO2 reduction. For the SHEV technology, the agencies sized the system
using a 50 kW starter/generator and a 70 kWh Li-ion battery pack. The estimates resulted in an
effectiveness range of 18 to 22 percent depending on the engine. The estimates assume no
engine downsizing so as to maintain vehicle performance and/or maintain towing and hauling
performance.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.4 Aerodynamics
Aerodynamic drag is an important aspect of the power requirements for Class 2b and 3
trucks. Because aerodynamic drag is a function of the cube of vehicle speed, small changes in
the aerodynamics of a Class 2b and 3 can reduce drag, fuel consumption, and GHG emissions.
Some of the opportunities to reduce aerodynamic drag in Class 2b and 3 vehicles are similar to
those in Class 1 and 2 (i.e., light-duty) vehicles. In general, these transferable features make the
cab shape more aerodynamic by streamlining the airflow over the bumper, grill, windshield,
sides, and roof. Class 2b and 3 vehicles may also borrow from light-duty vehicles certain drag
reducing accessories (e.g., streamlined mirrors, operator steps, and sun visors). The great variety
of applications for Class 2b and 3 trucks result in a wide range of operational speed profiles (i.e.,
in-use drive cycles) and functional requirements (e.g., shuttle buses that must be tall enough for
standing passengers, trucks that must have racks for ladders). This variety makes it challenging
to develop aerodynamic solutions that consider the entire vehicle.
Many factors affect a vehicle's aerodynamic drag and the resulting power required to
move it through the air. While these factors change with air density and the square and cube of
vehicle speed, respectively, the overall drag effect is determined by the product of its frontal area
and drag coefficient. Reductions in these quantities can therefore reduce fuel consumption and
CO2 emissions. Although frontal areas tend to be relatively similar within a vehicle class
(mostly due to market-competitive size requirements), significant variations in drag coefficient
can be observed. Significant changes to a vehicle's aerodynamic performance may need to be

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
implemented during a redesign (e.g., changes in vehicle shape). However, shorter-term
aerodynamic reductions, with a somewhat lower effectiveness, may be achieved through the use
of revised exterior components (typically at a model refresh in mid-cycle) and add-on devices
that are currently being applied. The latter list would include revised front and rear fascias,
modified front air dams and rear valances, addition of rear deck lips and underbody panels, and
lower aerodynamic drag exterior mirrors.
For this rule, the agencies considered two levels of aero improvements. The first level
includes such body features as air dams, tire spats, and perhaps one underbody panel resulting in
a 5 percent aerodynamic drag reduction. The agencies estimated the CO2 and fuel consumption
effectiveness of this first level of aerodynamic drag at 0.75 percent.
The second level which includes the features of level 1 plus additional body features such
as active grille shutters6, rear visors, larger under body panels or low-profile roof racks resulting
in a 10 percent aerodynamic drag reduction. The agencies estimated the CO2 and fuel
consumption effectiveness of this second level of aerodynamic drag at 1.5 percent. We present
cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.5	Tires
Typically, tires used on Class 2b/3 vehicles are not designed specifically for the vehicle.
These tires are designed for broader use and no single parameter is optimized. Similar to
vocational vehicles, the market has not demanded tires with improved rolling resistance thus far;
therefore, manufacturers have not traditionally designed tires with low rolling resistance for
Class 2b/3 vehicles. The agencies believe that a regulatory program that incentivizes the
optimization of tire rolling resistance, traction and durability can bring about GHG emission and
fuel consumption reductions of 1.1 percent from this segment based on a 10 percent reduction in
rolling resistance.
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.5.6	Mass Reduction
Mass reduction is a technology that can be used in a manufacturer's strategy to meet the
Heavy Duty Greenhouse Gas Phase 2 standards (although, as noted, it is not part of the agencies'
projected technology path for either the standards for pickups and vans, or any of the other
standards). Vehicle mass reduction (also referred to as "light-weighting"), decreases fuel
consumption and GHG emissions by reducing the energy demand needed to overcome inertia
forces, and rolling resistance. Automotive companies have worked with mass reduction
technologies for many years and a lot of these technologies have been used in production
vehicles. The weight savings achieved by adopting mass reduction technologies offset weight
gains due to increased vehicle size, larger powertrains, and increased feature content (sound
B For details on how active aerodynamics are considered for off-cycle credits, see the Technical Support Document
for Final Rulemaking for 2017-2025 Light-Duty Vehicle Greenhouse Gas Emission Standards and Corporate
Average Fuel Economy, August 2012, Chapter 5.2.2.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
insulation, entertainment systems, improved climate control, panoramic roof, etc.). Sometimes
mass reduction has been used to increase vehicle towing and payload capabilities.
Manufacturers employ a systematic approach to mass reduction, where the net mass
reduction is the addition of a direct component or system mass reduction, also referred to as
primary mass reduction, plus the additional mass reduction taken from indirect ancillary systems
and components, also referred to as secondary mass reduction or mass compounding. There are
more secondary mass reductions achievable for light-duty vehicles compared to heavy-duty
vehicles, which are limited due to the higher towing and payload requirements.
Mass reduction can be achieved through a number of approaches, even while maintaining
other vehicle functionalities. As summarized by NAS in its 2011 light duty vehicle report, there
are two key strategies for primary mass reduction: 1) changing the design to use less material; 2)
substituting lighter materials for heavier materials.112
The first key strategy of using less material compared to the baseline component can be
achieved by optimizing the design and structure of vehicle components, systems and vehicle
structure. Vehicle manufacturers have long used these continually-improving CAE tools to
optimize vehicle designs. For example, the Future Steel Vehicle (FSV) project sponsored by
World Auto Steel used three levels of optimization: topology optimization, low fidelity 3G
(Geometry Grade and Gauge) optimization, and subsystem optimization, to achieve 30 percent
mass reduction in the body structure of a vehicle with a mild steel unibody structure.113 Using
less material can also be achieved through improving the manufacturing process, such as by
using improved joining technologies and parts consolidation. This method is often used in
combination with applying new materials.
The second key strategy to reduce mass of an assembly or component involves the
substitution of lower density and/or higher strength materials. Material substitution includes
replacing materials, such as mild steel, with higher-strength and advanced steels, aluminum,
magnesium, and composite materials. In practice, material substitution tends to be quite specific
to the manufacturer and situation. Some materials work better than others for particular vehicle
components, and a manufacturer may invest more heavily in adjusting to a particular type of
advanced material, thus complicating its ability to consider others. The agencies recognize that
like any type of mass reduction, material substitution has to be conducted not only with
consideration to maintaining equivalent component strength, but also to maintaining all the other
attributes of that component, system or vehicle, such as crashworthiness, durability, and noise,
vibration and harshness (NVH).
If vehicle mass is reduced sufficiently through application of the two primary strategies
of using less material and material substitution described above, secondary mass reduction
options may become available. Secondary mass reduction is enabled when the load requirements
of a component are reduced as a result of primary mass reduction. If the primary mass reduction
reaches a sufficient level, a manufacturer may use a smaller, lighter, and potentially more
efficient powertrain while maintaining vehicle acceleration performance. If a powertrain is
downsized, a portion of the mass reduction may be attributed to the reduced torque requirement
which results from the lower vehicle mass. The lower torque requirement enables a reduction in
engine displacement, changes to transmission torque converter and gear ratios, and changes to

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
final drive gear ratio. The reduced powertrain torque enables the downsizing and/or mass
reduction of powertrain components and accompanying reduced rotating mass (e.g., for
transmission, driveshafts/halfshafts, wheels, and tires) without sacrificing powertrain
durability. Likewise, the combined mass reductions of the engine, drivetrain, and body in turn
reduce stresses on the suspension components, steering components, wheels, tires, and brakes,
which can allow further reductions in the mass of these subsystems. Reducing the unsprung
masses such as the brakes, control arms, wheels, and tires further reduce stresses in the
suspension mounting points, which will allow for further optimization and potential mass
reduction. However, pickup trucks have towing and hauling requirements which must be taken
into account when determining the amount of secondary mass reduction that is possible and so it
is less than that of passenger cars.
In September 2015, Ford announced that its MY 2017 F-Series Super duty pickup (F-
250) would be manufactured with an aluminum body and overall the truck will be 350 lbs lighter
(5 to 6 percent) than the current gen truck with steel.114'115 This is less overall mass reduction
than the resultant lightweighting effort on the MY 2015 F-150 which achieved up to a 750 lb
decrease in curb weight (12 to 13 percent) per vehicle.116 Strategies were employed in the F-250
to "improve the productivity of the Super Duty" in addition there were several safety systems
added including cameras, lane departure warning, brake assist, etc. If some of the mass
reduction efforts were not offset by other vehicle upgrades (size, towing, hauling, etc.), then
more mass reduction and greater fuel economy could have been realized. More details on the F-
250 will be known once it is released; however, a review of the F-150 vehicle aluminum
intensive design shows that it has an aluminum cab structure, body panels, and suspension
components, as well as a high strength steel frame and a smaller, lighter and more efficient
engine. The Executive Summary to Ducker Worldwide's 2014 report117 states that state that the
MY 2015 F-150 contains 1080 lbs of aluminum with at least half of this being aluminum sheet
and extrusions for body and closures. Ford's engine options for its light duty truck fleet includes
a 2.7L EcoBoost V-6. The integrated loop between Ford, the aluminum sheet suppliers, and the
aluminum scrap suppliers is integral to making aluminum a feasible lightweighting technology
option for Ford. It is also possible that the strategy of using aluminum body panels will be
applied to the heavy duty F-350 version when it is redesigned.118
We present cost estimates for this technology in Chapter 2.11 of this RIA.
2.6 Technology Application- SI Engines
This section summarizes the technologies the agencies project as a feasible path to
meeting the engine standards for spark-ignition engines used in vocational vehicles - that is
engines that are engine-certified and intended for vocational vehicles that will be GEM-certified.
These standards apply with respect to emissions measured over the FTP test cycle. This cycle is
described in Chapter 3.1. See Chapter 2.5 for spark-ignited engine technologies projected for the
Phase 2 HD pickup and van vehicle standards.
For the reasons discussed below, rather than setting a more stringent engine standard, the
agencies will maintain the MY 2016 fuel consumption and CO2 emission standards for SI
engines for use in vocational vehicles: 7.06 gallon/100 bhp-hr and 627 g CCh/bhp-hr, as
measured over the Heavy-duty FTP engine test cycle.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Heavy-duty spark-ignited (SI) engines are used in almost 30 percent of vocational
vehicles. Operators that choose gasoline engines do so for reasons similar to those for HD
complete pickups and vans. Gasoline engines have the advantage of being less expensive and
lower weight than diesels, but tend to also be less durable and have higher fuel consumption.
Thus, gasoline engines are most likely to be purchased for applications with lower annual VMT,
where fuel costs are less important than upfront costs.
When an Si-powered vocational vehicle is built by a non-integrated chassis manufacturer,
the engine is generally purchased from a company that also produces complete and/or
incomplete HD pickup trucks and vans. The primary certification path intended in this scenario
is for the engine to be engine-certified over the FTP and the vehicle to be GEM certified under
the GHG rules. This is common practice for CI engines, and in Phase 2 the agencies are
continuing this as the primary certification path for SI engines intended for vocational vehicles.
In Phase 1 we adopted a special provision aimed at simplifying compliance for
manufacturers of complete HD pickups and vans that also sell a relatively small number of
engines to non-integrated chassis manufacturers. This flexibility provision enables these
manufacturers to avoid meeting the separate SI engine standard, instead averaging them into the
applicable HD pickup and van fleet-wide average.0 These "loose" engine sales represent a very
small fraction of the Si-powered vocational vehicle market. The final Phase 2 program allows SI
engine manufacturers to sell a limited number of these "loose" SI engines to other chassis
manufacturers for use in vocational vehicles, through MY 2023.
The SI engines certified and sold as loose engines into the heavy-duty vocational vehicle
market are typically large V8 and V10 engines produced by General Motors and Ford. The
number of engine families certified in the past for this segment of vehicles is very limited and
has ranged between three and five engine models.119 Unlike the heavy-duty diesel engines
typical of this segment that are built for vocational vehicles, these SI engines are primarily
developed for chassis-certified heavy-duty pickup trucks and vans, but are also installed in
incomplete vocational vehicles.
Under the special Phase 1 provision, these loose engines need not be certified to engine-
based GHG and fuel consumption standards, but instead may be treated under the regulations as
though they are additional sales of the manufacturer's complete pickup and van products, on a
one-for-one basis. The pickup/van vehicle so chosen must be the vehicle with the highest
emission test weight that uses the engine (as this vehicle is likely to have the highest GHG
emissions and fuel consumption).0 However, if this vehicle is a credit-generator under the HD
pickup and van fleet averaging program, no credits would be generated by these engine-as-
vehicle contributors to the fleet average; they would be treated as just achieving the target
standard. If, on the other hand, the vehicle is a credit-user, the appropriate number of additional
credits would be needed to offset the engine-as-vehicle contributors. The purchaser of the
c See 40 CFR 1037.150(m) and 49 CFR 535.5(a)(7).
D Equivalent test weight is defined at 40 CFR 1037.104(d)(l 1) and is determined based on a vehicle's adjusted
loaded vehicle weight as specified in 40 CFR 86.129, except that for vehicles over 14,000 pounds, this may be
rounded to the nearest 500 pound increment.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
engine would treat it as any other certified engine, and would still need to meet applicable
vocational vehicle standards for the vehicles in which the engine is installed.
In deriving the stringency of the Phase 2 SI engine standard, the agencies first reviewed
the technology that was presumed in the MY 2010 Phase 1 baseline and the technology that was
projected to be adopted to meet the MY 2016 SI engine standard, finalized as part of the Phase 1
program. Engines certified to this standard would represent a logical level at which to set a
Phase 2 baseline performance level.
The agencies finalized MY 2016 standards that require manufacturers to achieve a 5
percent reduction in CO2 compared to the Phase 1 MY 2010 baseline. That MY 2010 baseline
engine was described in the Phase 1 Preamble at Section III.B.2.a.iii, as a naturally aspirated,
overhead valve V8 engine.120
In deriving the stringency of the MY 2016 gasoline engine standards, the agencies
projected 100 percent adoption of engine friction reduction, coupled cam phasing, and
stoichiometric gasoline direct injection (SGDI) to produce an overall 5 percent reduction from
the reference engine, over the engine FTP test cycle. Table 2-6 presents the technologies
projected to be present on an engine following this technology path.
Table 2-6 MY 2016 Technology Projection for SI Engines
TECHNOLOGY
ADOPTION
RATE
Coupled Cam Phasing
100%
Engine friction reduction
100%
SGDI
100%
In deciding whether to consider the above package as representing the Phase 2 baseline
performance of SI engines, the agencies reviewed available certification information and
consulted with stakeholders to determine the degree to which these projections match with
engines being produced today and engine product plans during the Phase 1 time frame. The
agencies have learned that no SI engine manufacturer has applied SGDI to this type of engine to
date, though cam phasing and engine friction reduction are widely being employed.
Section II.D.2(b) and Section V.C.l(b) of the Preamble discuss the agencies' response to
comments received on the application of SI engine technologies in the Phase 2 SI engine
standard and the vocational vehicle program, respectively. None of the comments received by
the agencies provided technical data on engine technology performance over the HD gasoline
engine FTP test procedure. Further, many engine technologies suggested to the agencies are
already presumed to be applied to SI engines, at application rates of 100 percent (see Table 2-6
above), to meet the MY 2016 engine standard. Because the agencies cannot count the
performance of those Phase 1 technologies in a Phase 2 standard, the difference between what
the commenters seek and what the agencies are adopting is considerably less than initially
appears (and that the commenters appear to believe).

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.7 Technology Application and Estimated Costs - CI Engines
2.7.1 Phase 1 Engine Standards
The agencies' initial premise is that the baseline CI engine for purposes of the Phase 2
engine standard must be the engine needed to meet the Phase 1 CI engine standard. Table 2-7
shows CO2 performance at the end of Phase 1. However, as explained in the next few sections,
there are some issues associated with these baselines for both tractor and vocational engines.
Consequently, the agencies adjusted these baseline values from those proposed.
Table 2-7 Baseline Phase 1 CO2 Standards (g/bhp-hr)
LHDD - FTP
MHDD - FTP
HHDD - FTP
MHDD - SET
HHDD - SET
576
576
555
487
460
2.7.2	Individual Technology Feasibility and Cost
The cost for combustion system optimization includes costs associated with several
individual technologies, specifically, improved cylinder head, turbo efficiency improvements,
EGR cooler improvements, higher pressure fuel rail, improved fuel injectors and improved
pistons. The cost estimates for each of these technologies are presented in Chapter 2.7 of this
RIA for heavy HD, medium HD and light HD engines, respectively.
The agencies have included the costs of model-based control development in the research
and development costs applied separately to each engine manufacturer.
2.7.3	Test Cycle Weighting
The current SET modes used for tractor engine certification in Phase 1 have a relatively
large weighting in C speed as shown in the middle column of the following table:

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-8 SET Modes Weighting Factors
SPEED/% LOAD
WEIGHTING FACTOR IN
WEIGHTING FACTOR IN

PHASE 1 (%)
PHASE 2 (%)
Idle
15
12
A, 100
8
9
B, 50
10
10
B, 75
10
10
A, 50
5
12
A, 75
5
12
A, 25
5
12
Cd
o
o
9
9
B, 25
10
9
C, 100
8
2
C, 25
5
1
C, 75
5
1
C, 50
5
1
Total
100
100
A:
23
45
B:
39
38
C:
23
5
It can be seen from the above table that 23 percent weighting is in C speed, which is
typically in the range of 1800 rpm for HHD engines. However, many of today's HHD engines
do not commonly operate at such a high speed in real world driving conditions, specifically
during cruise vehicle speed between 55 and 65 mph. The agencies received confidential
business information from a few vehicle manufacturers that support this observation.
Furthermore, one of the key technology trends is to down speed, moving the predominant engine
speed from the range of 1300-1400 rpm to the range of 1150-1200 rpm at a vehicle speed of 65
mph. This trend would make the predominant engine speed even further away from C speed.
Therefore, it can be argued that, if the current SET weighting factors were retained in Phase 2,
the test would not properly reflect real-world driving operations. A more detailed explanation
with supportive data on this matter can be found in the article.121 Accordingly, the agencies are
adjusting the weighting of the various modes in the SET cycle as presented in the third column
of Table 2-8.
As shown, the new SET mode weighting basically moves most of the C speed weighting
to A speed. It also slightly reduces the weighting factor on the idle speed. These values are
based on the confidential business information obtained from vehicle manufacturers.
2.7.4 Phase 2 Baseline for Tractor and Vocational Engines
As mentioned above, the Phase 2 baseline engine numerical values are changed from
those used at proposal. However, the reasons for these changes differ for tractor and vocational
engines. For the tractor engine, the reason for the change in the SET cycle baseline values is due
to the new SET weighting factors, shown in Table 2-8, even though the engine fueling map as a
function of the engine torque and speed is the same whether Phase 1 or Phase 2 SET weighting
factors are used. Since the tractor engine standards are set up based on a composite value over
the 13 modes of the SET, using the weighting factors shown in Table 2-8, the new adjusted

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
standards with the new weighting factors result in a new set of numerical values shown in Table
2-9. Compared to the values in Table 2-7, the values are about 1.1 to 1.2 percent lower because
of the new SET weighting structure.122
Table 2-9 Tractor Engine Baseline CO2 Performance (g/bhp-hr)
MHDD - SET
HHDD - SET
481
455
For the vocational engine standard, the new baselines are required because GHG
performance of vocational vehicle engines has improved significantly since the inception of the
Phase 1 standards, and therefore, the baselines reflecting the level of the Phase 1 standard are
unrepresentative. The latest 2016 federal certification data, as well as data posted on California
Air Resource Board (CARB) websites, show that many of the Phase 1 engines are not only easily
achieving the Phase 1 2017 standard, but in some instances, the proposed 2027 engine standards
as well! See Figure 2-15 and Figure 2-16.
595
575
555
535
BO
K 515
O
U
495
475
455

2017 Phase I standard (555g/hp-hr)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Engines
Figure 2-15 2016 certified HHD engines over FTP cycle

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review
M
fSI
O
u
660
640
620
600
580
560
540
520
500
480
2017
Phase I standard (576 g/hp-hr)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Engines
Figure 2-16 2016 certified MHD/LHD engines over FTP cycle
The major contributor to this achievement in the vocational engine sector is transient
control related technologies, such as thermal management. This is one of the most challenging
areas for which to project improvement due to the nature of transient behaviors and the limited
data available. These improvements were not yet reflected in the 2010 certification data
available at proposal. Specifically, an integrated SCR and DPF system, including their
hardware, composition of catalytic material, urea dosing strategy, was in an early, non-optimized
stage in 2010. The early production SCR+DPF system had not been fully optimized for thermal
management and urea dosing strategy. As a result, some of the thermal management measures,
such as tailpipe back pressure control, post-fuel injection, and intake throttle control, tended to
be less efficient during transient operation. The agencies have also learned from the recent
certification data, illustrated in the figures above, that LHD engines perform differently than
MHD engines, and therefore that it makes more sense to separate MHD and LHD engines rather
than combine them in a single standard as in Phase 1. In view of this situation, after the agencies
analyzed all available certification data, we average the best possible engines from each
manufacturer, and consequently, the baselines of 2018 vocational engines for Phase 2 are
adjusted as follows.
Table 2-10 Vocational Engine Baseline CO2 Performance (g/bhp-hr)
LHD - FTP
MHD- FTP
HHD - FTP
576
558
525
2.7.5 Technology Packages
The agencies assessed the impact of technologies over each of the SET modes to project
an overall improvement for a tractor engine. It should be pointed out that the technology
packages discussed in this section are relevant for both tractor and vocational engines, with the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
exception of WHR related technologies. The agencies considered improvements in parasitic and
friction losses through bearing and piston ring designs to reduce friction, improved lubrication
and oils, and improved water pump and oil pump designs to reduce parasitic losses. The after-
treatment improvements are available through additional improvements that lower backpressure
of the systems, further optimization of the engine-out NOx levels, and further reduction in
ammonia slip from the SCR. Improvements to the EGR system and air flow through the intake
and exhaust systems, including through turbochargers, can also produce engine efficiency
improvements. Improvements in combustion chamber design and materials and fuel injection
control can reduce the fuel consumption of the engine. Engine downsizing is part of this
consideration with respect to improving efficiency, specifically when this technology is used
together with engine down-speeding. Although one of the most effective single technologies to
improve engine efficiency is the application of waste heat recovery (WHR) via the Rankine heat
engine cycle, the agencies do not project that this technology will have significant market
adoption until MY 2024. The reason for this is that this type of WHR system is currently only at
a pre-prototype stage of development. Furthermore, the system itself includes many components
that still require extensive field testing to assure reliability. The high technology cost, longer
payback period (if the cost and benefit of using WHR is considered in isolation), concern about
commercial acceptance (given the technology complexity, cost, concern about reliability leading
to demurrage costs and warranty claims in early model years) again point to a longer necessary
lead time for introducing this technology. See Chapter 2.3.9 above for more detailed discussions
on WHR. The agencies received detailed information from various stakeholders, who provided
information that was claimed as confidential business information (CBI). Examples include
technology improvement effectiveness information at each or some of 13 SET modes,
information on the list of components in the system, the working fluid of the system, and the
overall design.
While many effective technologies are considered for this rulemaking, it is important to
point out that the benefits of these technologies are not additive. For example, when multiple
technologies are applied to an engine, it is incorrect to simply sum the individual technologies'
effectiveness to arrive at an overall combined effectiveness of the technologies. We have
received a number of public comments regarding this non-additive effect. Most of them focus on
the agencies' projections of our so-called "dis-synergy" effect and our use of a dis-synergy factor
to account for this effect. This effect could also be called a negative synergy because it is a
decrease in technology effectiveness as a result of multiple technologies being applied to an
engine. Some commenters recommended that we adopt lower numeric values of our dis-synergy
factors, but a few commenters recommended higher dis-synergy factors than what we proposed.
A number of NGOs maintained that it was inappropriate to have a single dis-synergy factor. The
following paragraphs provide some background on this effect and our rationale for how we
developed numeric dis-synergy factors and applied them within our final stringency analysis.
As background, it is helpful to first review how engine fuel efficiency technologies
interact with one another. One example is the interaction between WHR and other technologies,
such as combustion, friction reduction, and fuel injection system improvements. WHR
effectiveness is directly proportional to the amount of thermodynamic available energy (i.e.,
energy available for conversion into mechanical work) provided from an engine's sources of
waste heat. In a modern internal combustion engine, these sources include exhaust gas energy
available from the EGR cooler and tailpipe, and from the coolant and lubricating oil systems.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Therefore, decreasing the amount of available energy from these sources reduces the
effectiveness of WHR. Some of the fuel efficiency technologies we identify in our stringency
analysis decrease the amount of available energy from these sources. For example, advancing
fuel injection timing will improve efficiency to a certain point, but it will also decrease available
exhaust energy by lowering exhaust temperature, and thus exhaust WHR effectiveness would
decrease. To a lesser extent, reducing bearing friction or piston ring-wall friction improves fuel
efficiency, but this also leads to less heat transfer to the coolant; and hence lower available
energy for WHR. As another example, increasing compression ratio can improve combustion
thermal efficiency (until the peak cylinder pressure rises past a given mechanical limit), but this
in turn increases friction losses at piston rings and bearings. As another example increasing fuel
injection pressure provides more opportunity for fuel injection optimization (e.g., enabling more
multiple injection events), which can improve fuel efficiency, but this will in turn increase fuel
pump parasitic energy losses. In another example, increasing turbocharger efficiency can
improve fuel efficiency, but this will also reduce EGR flow due to lower back pressure, thus
potentially increasing NOx, and also reducing the exhaust gas energy that can be utilized by
waste heat recovery devices, such as turbo-compound and Rankine cycle systems. Increasing
NOx would also put more demand on the after-treatment system or force less fuel efficient fuel
injection timing. There are more examples, but in conclusion, there are numerous complex
interactions between fuel efficiency technologies. In the next few paragraphs we describe how
we accounted for those interactions that lead to a dis-synergy effect.
If the agencies possessed the resources to conduct a multi-million dollar multi-year effort
to very accurately quantify all of the potential engine technology fuel efficiency dis-synergies,
we would have embarked on the development and calibration of a comprehensive engine cycle
computer simulation model several years ago. Such an effort would lead to the development of
an engine cycle simulation model, which would consist of all engine components, including sub-
models for fuel injection systems and combustion chambers; piston ring and bearing friction and
heat transfer; intake and exhaust systems, including EGR system, turbochargers, after-treatment
devices; and Rankine cycle or other WHR systems. Calibrating and validating such a model
would require tremendous laboratory testing resources to conduct the requisite component-level
and engine-level testing to gain confidence in the prediction capability of such a model. The
most challenging, and perhaps somewhat impossible, part of this comprehensive approach would
be to complete some sort of experimental validation step to demonstrate that the model
accurately predicts the combined performance of engine technologies that do not yet exist.
This level of effort is beyond the scope of the agencies' resources. However, fortunately,
other research and development programs have sufficiently reported on the magnitude of these
dis-synergies to the point that reliable estimates may be projected. The agencies were able to
rely upon information made available through research programs like DOE's SuperTruck
Program, where a number of major engine manufacturers partnered with DOE to co-fund
advanced high-efficiency engine development.23'25'26'30 In each of the manufacturer's
SuperTruck programs, more than five years and greater than ten million dollar budgets were
spent to model and develop pre-prototype engines. The agencies initially asked manufacturers if
they would share their proprietary SuperTruck engine cycle simulation models with the agencies.
This request was understandably declined because such models contain manufacturers' most
advanced and valuable competitive information. Therefore, based on the best information

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
available, the agencies developed a single set of empirical constants to account for these known
dis-synergies, and we applied these constants within our stringency analyses.
In this empirical approach, all technologies under consideration are combined according
to the National Academies recommended formula for combining the fuel efficiency benefits of
multiple engine (and vehicle) technologies:1
Equation 2-1: Formula for Combining Fuel Efficiency Benefits
%FEM=\-Yl(\-fr%FE:I)
i
In this equation,/; represents the market penetration of technology and %FE\ is the
percent fuel efficiency improvement (i.e., effectiveness) associated with technology i. The
resulting %FEtota\ is the combined fuel efficiency improvement due to all technologies, but with
no accounting of technology dis-synergies, like those described above. To account for dis-
synergies, %FEto\a\ is multiplied by a single numerical constant, which we call a dis-synergy
factor. This dis-synergy factor has two extreme bounds: a lower bound of 0.0 and an upper
bound of 1.0. And practically speaking, it is highly unlikely that adding a technology to an
engine that leads toward a dis-synergy factor on the order of 0.5 would even be considered a fuel
efficiency improving technology. Therefore, the agencies focused on determining where within
the range of 0.5-1.0 we should project this dis-synergy factor to be.
There are two key steps in determining an overall dis-synergy factor. The first step is to
determine the effectiveness of each key technology. For this step we relied upon our collection
of technology information from DOE's SuperTruck Program, from individual manufacturers and
technology suppliers, and from peer reviewed journal articles and presentations at technical
conferences. This information includes performance data on individual components and data on
engines with different combinations of technology. The second step is to iteratively solve for the
most probable single dis-synergy factor that matches the diverse set of data that we collected.
This step started by first running a simplified engine cycle simulation model (GT Power) to
simulate individual technology benefits, and then we ran the model with different technology
combinations. Finally, the results of the simplified model were compared to the data we had
collected. Note that while we were not able to validate this model to be accurate in an absolute
sense, the relative trends output by the model were consistent with the data we have in-hand.
With this model we determined a range of dis-synergy factors and the value of the factor
depended in part on the selection of technology packages. We found that this constant varies in
the range of 0.75 - 0.90. This range is further supported by separate, independent studies
performed by SwRI that were sponsored by SwRI report.7 Based upon our conclusion of this
range, the agencies are not going to adopt a dis-synergy factor of 0.95, which was requested of us
in comment. Based on our modeling and corroborative data, 0.95 would be inappropriately high
and likely not achievable.
Table 2-11 lists the potential emission reduction technologies together with the agencies'
estimated market penetration for tractor engines, along with the dis-synergy factors developed by
the agencies. A dis-synergy factor of 0.85 is adopted for 2021, and 0.90 is used for 2024 and
2027. This increase in the value of the dis-synergy factor represents the results of manufacturers
increasing their research and development efforts to optimize engine technologies together as a

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
package, in order to comply with the HD Phase 2 engine standards. The agencies have
accounted for our projected increased investment in research and design by including respective
incremental vehicle cost increases in our cost analysis. By increasing the dis-synergy factor
from 0.85 to 0.90 in MY 2024, our MY 2024 and MY 2027 engine standards are based on our
projections of increased technology package optimization. For example, we project that the
friction increase associated with the use of higher compression ratios leading to higher peak
cylinder pressures will be compensated for by friction reduction via improvements in piston ring
and crankshaft bearing design, as well as by improved oil lubricants. It should be noted that
Table 2-11 does not include individual modes of technology improvement over the 13 individual
modes of the SET. This is a result of the fact that we aggregated CBI data obtained from
manufacturers in order to avoid releasing proprietary intellectual property within this
presentation of our analysis.
Table 2-11 Projected Tractor Engine Technologies and Reduction, Percent Improvements Beyond Phase 1,
2017 Engine as Baseline
SET MODE
SET
WEIGHTED
REDUCTION
(%) 2020-2027
MARKET
PENETRATION
(2021)
MARKET
PENETRATION
(2024)
MARKET
PENETRATION
(2027)
Turbo compound with clutch
1.8%
5%
10%
10%
WHR (Rankine cycle)
3.6%
1%
5%
25%
Parasitic/Friction (Cyl Kits,
pumps, FIE), lubrication
1.4%
45%
95%
100%
Aftertreatment (lower dP)
0.6%
30%
95%
100%
EGR/Intake & exhaust
manifolds/Turbo /VVT/Ports
1.1%
45%
95%
100%
Combustion/FI/Control
1.1%
45%
95%
100%
Downsizing
0.3%
10%
20%
30%
Weighted reduction (%)

1.8%
4.0%
4.8%
Down speed impact on 13
modes

0.1%
0.2%
0.3%
Total reduction

1.8%
4.2%
5.1%
The agencies used the current market information and literature values to project what
technologies would be available in the time frame beyond 2021 and what their market
penetration would be. Chapter 2.3.9 details the reasons of why many of the technology market
penetration rates would follow an S-shape curve, which is most applicable to WHR with the
Rankine cycle technology. In spite of the fact that all trucks with WHR Ranking cycle
technology were still in the R/D stage or in the pre-prototype stage, the successful
demonstrations in real world driving conditions such as the DOE-sponsored SuperTruck
program, shows the technology that could be brought into market earlier because of the
technology's effectiveness. The agencies project that WHR with Rankine cycle will gain
momentum with time because of the potential for large emission reductions. It is unlikely that
we will see large scale production of WHR in the 2021 MY because of the many challenges that
industry faces, as described in Chapter 2.3.9. The agencies expect a market penetration of 1
percent in 2021. It will take time for WHR to have a sizeable market penetration due to system
complexity and it is estimated to be 5 percent in 2024; 25 percent in 2027, which follows an S-

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
shape curve, beginning with slow initial adoption, then more rapid adoption, and then a leveling
off as the market saturates. More discussion on WHR market penetration can be seen in Chapter
2.3.9. As there discussed, this projected trend is consistent with the finding reported by
NACEF36 in terms of the S-shape curve.
As for WHR with turbo-compound technology, only Daimler uses turbo-compound in
their DDI5 and DDI6 engines. They are phasing out turbo-compounding in the future and
replacing it with asymmetric turbo technology for most applications. Volvo just announced that
it would bring its newly-developed turbo-compound technology to market in mainly tractor
applications. Combining both manufacturers' market shares, the agencies estimate a 5 percent
market share for turbo-compound technologies in 2021. Additional production from these
manufacturers or from some additional manufacturers that could adopt this technology in some
of their trucks could push the market penetration up to 10 percent after 2024.
All other technologies, with the exception of downsizing, such as parasitic/friction loss,
aftertreatment, air breathing system, and combustion, which have been on the market already for
substantial periods and are relatively mature when compared to WHR, would follow the same
path for market penetration, 45 percent in 2021, 95 percent in 2024, and 100 percent in 2027.
The agencies don't expect high market penetration of engine downsizing, because downsizing
has a trade-off with reliability and resale values. We do see the potential for this type of
technology as it can be effective when combined with down speeding, specifically when power
demand drops due to more efficient engine and vehicle platforms. However, unlike other
technologies, such as parasitic/friction, aftertreatment, and combustion, the technology of down-
speeding together with downsizing would face the issue associated with resale value. As such,
the fleet may be reluctant to accept this technology as others until the reliability is proven.
Therefore, we don't expect that the market penetration would be as high as other technologies. It
comes down to a matter of choice. We project 10 percent, 20 percent, and 30 percent market
penetration rates in 2021, 2024, and 2027 respectively.
The tractor engine technology compliance pathway shown in Table 2-11 is only one of
many paths that manufacturers might adopt in order to achieve the 1.8 percent, 4.2, and 5.1
percent reduction goals in 2021, 2024 and 2027 respectively. This particular compliance
pathway relies on some use of WHR - small initial market penetration in 2021 and 2024,
increasing to 25 percent in MY 2027.E This projected rate of penetration in MY 2027 is greater
than projected at proposal (where the agencies' compliance pathway had WHR used in tractor
engines). One of the key reasons to increase the market penetration on WHR with Rankine cycle
technology was based on the valuable and credible CBI information obtained from a meeting
with Cummins.123 It can be mentioned that, during the meeting, Cummins provided detailed
technical information on both technology effectiveness and reliability on an entire engine system
level as well as a component level, indicating that the agency's early projection with 15 percent
on WHR was conservative, and should be increased even with their current engine platform.
Considering that sleeper cab and day cab are about 50-50 percent share on the market, and also
considering that Cummins' engine Class 8 market share is in the range of 35-45 percent in the
past few years and is expected to stay in the same range, this can be translated to 17.5-22.5
percent market share in the sleeper cab segment just from one manufacturer. Although the WHR
E As will be seen in Chapter 2.8, much higher market penetration of WHR is used in the sleeper cab engine.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
technology is most likely and most effectively applied to sleeper cabs, it would not be surprising
that a very small portion of day cabs could utilize this type of technology depending on their
driving routes. If other manufacturers can put their WHR Rankine cycle system in a pilot trial
manner with just a few percent market share, it could reach 25 percent share on the market.
In addition to the technologies mentioned above, down speeding effects are also part of a
projected technology package for tractor engines, and for vocational engines that share the same
hardware as tractor engines. Down speeding is performed by systematically shifting the engine
peak torque curve to a lower speed region of the engine map and also increasing the overall peak
torque at this lower speed. This allows you to take advantage of the use of a lower vehicle axle
ratio to enable the engine to spend much of its operating time in its most efficient spot on the
map. We expect that down speeding will take place in three sequential steps in 2021, 2024, and
2027, with engine peak torque shifting to the highest torque at the lowest speed in 2027.
The changes to engine peak torque and associated power for down speed engines has a
different effect on the 13 modes of the SET when compared to a 2018 baseline engine. The
effect is varied based on the engine map characteristics, such as the location of the sweet spot
and the shape of the peak torque curve. We utilized a large number of engine fuel maps to
investigate the impact of down speeding on composite fuel consumption over the SET
certification cycle for different engine fuel map shapes. We found that the benefit varied from
no improvement to 0.6 percent while the average benefit is around 0.3 percent for the 2027
torque curve used in our analysis. Engine fuel maps that are less aggressive in peak torque
behavior, such as 2021 engine map, show less of an effect on fuel consumption reduction.
Therefore, we conclude that fuel consumption reductions due solely to the changes in the 13
mode SET speed and load are 0.1 percent, 0.2 percent, and 0.3 percent for 2021, 2024, and 2027,
respectively.
Figure 2-17, Figure 2-18, and Figure 2-19 contain the 2018 baseline engine fuel maps for
350 Hp, 455 Hp, and 600 Hp rating engines. The 350 Hp engine will be used for class 7 tractors
and some HHD vocational vehicles. The 455 Hp engine will be used for all HHD tractors with
sleeper cabs and day cabs as well as some HHD vocational vehicles. The 600 Hp engine is only
used for Heavy Haul tractors.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2018 Baseline Engine 350hp / 11L BSFC (g / kW * hr)
1600
1400
1200
1000
 1000
o-
o
H
800
600
400
235
200
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-18 2018 Baseline Engine Fuel Map used in GEM for a 455 Hp Rating

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Engine 600hp / 15L BSFC ( g / kW * hr)
Figure 2-19 2018 Baseline Engine Fuel Map used in GEM for a 600 Hp Rating
The agencies considered the same technology package developed for the HHD diesel
engines for vocational LHD diesel and MHD diesel engines. The technology package includes
parasitic and friction reduction, improved lubrication, aftertreatment improvements, EGR system
and air flow improvements, and combustion improvements. WHR technology is not part of the
package as WHR is not as efficient over transient operation, which is the principal operating
mode for vocational vehicles, even regional vehicles, since transient operation still comprises a
large portion of overall regional vehicle operation. One difference between tractor and
vocational engines is the model based control used over transient operation, which is applied to
operation over the FTP cycle. Chapter 2.3.3 details the model based control. Table 2-12 below
lists technologies and projected penetration rates which are the predicate for the standard for the
various vocational vehicle engines. The same dis-synergy factors that were generated for
tractors are also used. As is true of all the projected compliance pathways/ there are other
(usually myriad) ways to achieve the standard.
The market penetration rate and technology effectiveness estimates shown in Table 2-12
were developed using CBI data provided by engine manufacturers in conjunction with the
agencies' engineering judgment using the same principles outlined previously for tractor engines.
In terms of effectiveness, the model based control used over transient operation, which is
described in Chapter 2.3.3, would be one of the most effective technologies, but it would take
significant effort to develop and put it into production. An example of this technology is the
neural network approach developed by Daimler.19-20 One concern surrounding the use of this
technology is that it is still not clear how it will interact with on-board diagnostics (OBD). For
example, one of the purposes of the model based control is to use physical models to predict the
engine performance. As a result of that, the number of sensors in theory could be reduced, such
as one of the NOx sensors, or a few temperature sensors. On the other hand, OBD would largely
F The exception being those standards where a design is mandated, as for certain non-aero trailers.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
rely on the sensors to collect data. If one of the engine components malfunctions, and the
sensors that were in place to identify the issue were removed because of model based control,
OBD would not be able to diagnose the issue correctly. It is not clear how this issue can be
effectively resolved if some of sensors would be removed. We expect a 25 percent market
penetration in 2021, 30 percent in 2024, and 40 percent in 2027. All other technologies in Table
2-10 are relatively more mature than model based control, and therefore, higher market
penetration is projected. It should be pointed out that in developing standard stringency, the
technologies' effectiveness is applied to all the engines including Regional, Multipurpose, and
Urban vehicles, since the same engine hardware will be used for all of these applications.
Table 2-12 Projected Vocational Engine Technologies and Reduction, Percent Improvements Beyond
Baseline Engine
TECHNOLOGY
GHG
EMISSIONS
REDUCTION
2020-2027
MARKET
PENETRATION
2021
MARKET
PENETRATION
2024
MARKET
PENETRATION
2027
Model based control
2.0%
25%
30%
40%
Parasitic /Friction
1.5%
60%
90%
100%
EGR/Air/WT /Turbo
1.0%
60%
90%
100%
Improved AT
0.5%
30%
60%
100%
Combustion Optimization
1.0%
60%
90%
100%
Weighted reduction (%)-
L/M/HHD

2.3%
3.6%
4.2%
Figure 2-20 and Figure 2-21 are the 2018 baseline engine fuel maps used in GEM for the
270 Hp and 200 Hp rated engines. The 2018 baseline engines with 350 Hp and 455 Hp that are
used for vocational vehicles share the same engines as tractors, and therefore, there is no need to
display their maps here.
2018 Baseline Engine 270hp / 7L BSFC ( g / kW * hr)
900
800
700
600
500
0)
F 400
o
I—
300
235
245
200
265
265
100
800 1000 1200 1400 1600 1800 2000 2200 2400 2600
Speed ( RPM )
Figure 2-20 2018 Baseline Engine Fuel Map used in GEM for a 270 Hp Rating

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2018 Baseline Engine 200hp / 7L BSFC ( g / kW * hr)
900
800
700
600
6 500
h 400
300
235
250
270
200
100
800 1000 1200 1400 1600 1800 2000 2200 2400
Speed ( RPM)
Figure 2-21 2018 Baseline Engine Fuel Map used in GEM for a 200 Hp Rating
2.7.6 2021 Model Year HHP Diesel Engine Package for Tractors
As can be seen in Table 2-11, the composite CO2 reduction (the product of the
technology efficiency and projected technology penetration rates shown in that table) for a MY
2021 tractor engine over the SET cycle is 1.8 percent. With this reduction, the numerical
stringency values for 2021 can be derived from the baseline engine with new Phase 2 weighting
factors. Table 2-13 below shows the 2021 model year tractor engine standards.
Table 2-13 2021 Model Year Standards - Tractors

MHDD- SET
HHDD - SET
CO2 Emissions (g CO;/bhp-hr)
473
4474
Fuel Consumption (gal/100 bhp-lir)
4.6464
4.3910
The cost estimates for the MY 2021 HHD diesel engine packages can be developed from
the same information (i.e. technologies on which standard stringency is premised and projected
penetration rates) as shown in Table 2-14. We present technology cost estimates along with
adoption rates in Chapter 2.11 of this RIA. We present package cost estimates in greater detail
in Chapter 2.12 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-14 Technology Costs as Applied in Expected Packages for MY2021 Tractor Diesel Engines relative
to the Flat Baseline (2013$)a

MEDIUM
HEAVY

HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$7
$7
Valve Actuation
$84
$84
Cylinder Head (flow optimized, increased firing pressure, improved thermal
management)
$3
$3
Turbocharger (improved efficiency)
$9
$9
Turbo Compounding
$51
$51
EGR Cooler (improved efficiency)
$2
$2
Water Pump (optimized, variable vane, variable speed)
$44
$44
Oil Pump (optimized)
$2
$2
Fuel Pump (higher working pressure, increased efficiency, improved pressure
regulation)
$2
$2
Fuel Rail (higher working pressure)
$5
$5
Fuel Injector (optimized, improved multiple event control, higher working
pressure)
$5
$5
Piston (reduced friction skirt, ring and pin)
$1
$1
Valve Train (reduced friction, roller tappet)
$39
$39
Waste Heat Recovery
$71
$71
"Right sized" engine
-$41
-$41
Total
$284
$284
Note:
a Costs presented here include projected technology penetration rates presented in Table 2-11. These costs include indirect costs
via markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and
how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.7.7 2021 Model Year LHD/MHD/HHD Diesel Engine Package for
Vocational Vehicles
From Table 2-12, the reduction of CO2 for 2021 model years of all LHD/MHD/HHD
vocational diesel engines is 2.3 percent. Table 2-15 below shows the 2021 model year
vocational engine standards.
Table 2-15 2021 Model Year Standards — Vocational

LHDD -
FTP
MHDD -
FTP
HHDD -
FTP
CO2 Emissions (g CCh/bhp-hr)
563
545
513
Fuel Consumption (gal/100 bhp-hr)
5.5305
5.3536
5.0393
The cost estimates for the MY 2021 vocational diesel engines are shown in Table 2-16.
We present technology cost estimates along with adoption rates in Chapter 2.11 of this RIA. We
present package cost estimates in greater detail in Chapter 2.12 of this RIA and adoption rates in
Chapter 2.9.1.2.2.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-16 Technology Costs as Applied in Expected Packages for MY2021 Vocational Diesel Engines
relative to the Flat Baseline (2013$)a

LIGHT
MEDIUM
HEAVY

HD
HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$8
$8
$8
Valve Actuation
$93
$93
$93
Cylinder Head (flow optimized, increased firing pressure, improved
thermal management)
$6
$3
$3
Turbocharger (improved efficiency)
$10
$10
$10
EGR Cooler (improved efficiency)
$2
$2
$2
Water Pump (optimized, variable vane, variable speed)
$58
$58
$58
Oil Pump (optimized)
$3
$3
$3
Fuel Pump (higher working pressure, increased efficiency, improved
pressure regulation)
$3
$3
$3
Fuel Rail (higher working pressure)
$8
$6
$6
Fuel Injector (optimized, improved multiple event control, higher
working pressure)
$8
$6
$6
Piston (reduced friction skirt, ring and pin)
$1
$1
$1
Valve Train (reduced friction, roller tappet)
$70
$52
$52
Model Based Controls
$29
$29
$29
Total
$298
$275
$275
Note:
a Costs presented here includes projected technology penetration rates presented in Table 2-12. These costs include indirect costs
via markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and
how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.7.8 2024 Model Year HHDD Engine Package for Tractors
The agencies assessed the impact of technologies over each of the SET modes to project
an overall improvement in the 2024 model year. The agencies considered additional
improvements in the technologies included in the 2021 model year package. Compared to the
2021 technology package, the technology package in 2024 considers higher market adoption as
shown in Table 2-11, thus deriving a reduction of 4.2 percent. Table 2-17 below shows the 2024
model year tractor engine standards.
Table 2-17 2024 Model Year Standards - Tractors

MHDD- SET
HHDD - SET
CO2 Emissions (g CCh/bhp-hr)
461
436
Fuel Consumption (gal/100 bhp-hr)
4.5285
4.2829
The cost estimates for the MY 2024 tractor diesel engines are shown in Table 2-18. We
present technology cost estimates along with adoption rates in Chapter 2.11 of this RIA. We
present package cost estimates in greater detail in Chapter 2.12 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-18 Technology Costs as Applied in Expected Packages for MY2024 Tractor Diesel Engines relative
to the Flat Baseline (2013$)a

MEDIUM
HEAVY

HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$14
$14
Valve Actuation
$169
$169
Cylinder Head (flow optimized, increased firing pressure, improved thermal
management)
$6
$6
Turbocharger (improved efficiency)
$17
$17
Turbo Compounding
$93
$93
EGR Cooler (improved efficiency)
$3
$3
Water Pump (optimized, variable vane, variable speed)
$85
$85
Oil Pump (optimized)
$4
$4
Fuel Pump (higher working pressure, increased efficiency, improved pressure
regulation)
$4
$4
Fuel Rail (higher working pressure)
$9
$9
Fuel Injector (optimized, improved multiple event control, higher working
pressure)
$10
$10
Piston (reduced friction skirt, ring and pin)
$3
$3
Valve Train (reduced friction, roller tappet)
$77
$77
Waste Heat Recovery
$298
$298
"Right sized" engine
-$82
-$82
Total
$712
$712
Note:
a Costs presented here reflect projected technology penetration rates presented in Table 2-11. These costs include indirect costs
via markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and
how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.7.9 2024 Model Year LHD/MHD/HHD Diesel Engine Package for Vocational
Vehicles
The agencies developed the 2024 model year LHD/MHD/HHD vocational diesel engine
package based on additional improvements in the technologies included in the 2021 model year
package as shown in Table 2-12. The projected impact of these technologies provides an overall
reduction of 3.6 percent over the 2018 model year baseline. Table 2-19 below shows the 2024
model year vocational engine standards.
Table 2-19 2024 Model Year Standards - Vocational

LHDD -
FTP
MHDD -
FTP
HHDD -
FTP
CO2 Emissions (g CCh/bhp-hr)
555
538
506
Fuel Consumption (gal/100 bhp-hr)
5.4519
5.2849
4.9705
Costs for the MY 2024 vocational diesel engines are shown in Table 2-20. We present
technology cost estimates along with adoption rates in Chapter 2.11 of this RIA. We present
package cost estimates in greater detail in Chapter 2.12 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-20 Technology Costs as Applied in Expected Packages for MY2024 Vocational Diesel Engines
relative to the Flat Baseline (2013$)a

LIGHT
MEDIUM
HEAVY

HD
HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$14
$14
$14
Valve Actuation
$160
$160
$160
Cylinder Head (flow optimized, increased firing pressure, improved
thermal management)
$10
$6
$6
Turbocharger (improved efficiency)
$16
$16
$16
EGR Cooler (improved efficiency)
$3
$3
$3
Water Pump (optimized, variable vane, variable speed)
$81
$81
$81
Oil Pump (optimized)
$4
$4
$4
Fuel Pump (higher working pressure, increased efficiency, improved
pressure regulation)
$4
$4
$4
Fuel Rail (higher working pressure)
$11
$9
$9
Fuel Injector (optimized, improved multiple event control, higher
working pressure)
$13
$10
$10
Piston (reduced friction skirt, ring and pin)
$2
$2
$2
Valve Train (reduced friction, roller tappet)
$97
$73
$73
Model Based Controls
$32
$32
$32
Total
$446
$413
$413
Note:
a Costs presented here include project technology penetration rates presented in Table 2-12. These costs include indirect costs via
markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and how
it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.7.10 2027 Model Year HHDD Engine Package for Tractor
The agencies assessed the impact of technologies over the SET composite test cycle to
project an overall improvement in the 2027 model year. The agencies considered additional
improvements in the technologies included in the 2024 model year package. Compared to 2021
technology package, the technology package in 2027 considers higher market adoption, thus
deriving emission reductions of 5.1 percent as shown in Table 2-11. Table 2-21 below shows the
2027 model year tractor engine standards.
Table 2-21 2027 Model Year Standards - Tractors

MHDD- SET
HHDD - SET
CO2 Emissions (g CCh/bhp-hr)
457
432
Fuel Consumption (gal/100 bhp-hr)
4.4892
4.2436
The costs for the MY 2027 tractor diesel engines are shown in Table 2-22. We present
technology cost estimates along with adoption rates in Chapter 2.12 of this RIA. We present
package cost estimates in greater detail in Chapter 2.13 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-22 Technology Costs as Applied in Expected Packages for MY2027 Tractor Diesel Engines relative
to the Flat Baseline (2013$)a

MEDIUM
HEAVY

HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$15
$15
Valve Actuation
$172
$172
Cylinder Head (flow optimized, increased firing pressure, improved thermal
management)
$6
$6
Turbocharger (improved efficiency)
$17
$17
Turbo Compounding
$89
$89
EGR Cooler (improved efficiency)
$3
$3
Water Pump (optimized, variable vane, variable speed)
$85
$85
Oil Pump (optimized)
$4
$4
Fuel Pump (higher working pressure, increased efficiency, improved pressure
regulation)
$4
$4
Fuel Rail (higher working pressure)
$9
$9
Fuel Injector (optimized, improved multiple event control, higher working
pressure)
$10
$10
Piston (reduced friction skirt, ring and pin)
$3
$3
Valve Train (reduced friction, roller tappet)
$77
$77
Waste Heat Recovery
$1,208
$1,208
"Right sized" engine
-$123
-$123
Total
$1,579
$1,579
Note:
a Costs presented here include projected technology penetration rates presented in Table 2-11. These costs include indirect costs
via markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and
how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.7.11 2027 Model Year LHD/MHD/HHD Diesel Engine Package for Vocational
Vehicles
The agencies developed the 2027 model year LHD/MHD/HHD vocational diesel engine
package based on additional improvements in the technologies included in the 2021 model year
package as shown in Table 2-12. The projected impact of these technologies provides an overall
emission reduction of 4.2 percent over the 2017 model year baseline. Table 2-23 below shows
the 2027 model year standards.
Table 2-23 2027 Model Year Standards - Vocational

LHDD - FTP
MHDD- FTP
HHDD - FTP
CO2 Emissions (g CCh/bhp-hr)
552
535
503
Fuel Consumption (gal/100 bhp-hr)
5.4224
5.2554
4.9411
Costs for MY 2027 vocational diesel engines are shown in Table 2-24. We present
individual technology cost estimates in Chapter 2.11 of this RIA and adoption rates for
vocational vehicle engines in Chapter 2.9.1 of this RIA. We present package cost estimates in
greater detail in Chapter 2.12 of this RIA.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-24 Technology Costs as Applied in Expected Packages for MY2027 Vocational Diesel Engines
relative to the Flat Baseline (2013$)a

LIGHT
MEDIUM
HEAVY

HD
HD
HD
Aftertreatment system (improved effectiveness SCR, dosing, DPF)
$15
$15
$15
Valve Actuation
$172
$172
$172
Cylinder Head (flow optimized, increased firing pressure, improved
thermal management)
$10
$6
$6
Turbocharger (improved efficiency)
$17
$17
$17
EGR Cooler (improved efficiency)
$3
$3
$3
Water Pump (optimized, variable vane, variable speed)
$85
$85
$85
Oil Pump (optimized)
$4
$4
$4
Fuel Pump (higher working pressure, increased efficiency, improved
pressure regulation)
$4
$4
$4
Fuel Rail (higher working pressure)
$11
$9
$9
Fuel Injector (optimized, improved multiple event control, higher
working pressure)
$14
$10
$10
Piston (reduced friction skirt, ring and pin)
$3
$3
$3
Valve Train (reduced friction, roller tappet)
$102
$77
$77
Model Based Controls
$41
$41
$41
Total
$481
$446
$446
Note:
a Costs presented here include projected technology penetration rates presented in Table 2-12. These costs include indirect costs
via markups along with learning impacts. For a description of the markups and learning impacts considered in this analysis and
how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
2.8 Technology Application and Estimated Costs - Tractors
2.8.1 Defining the Baseline Tractors
The fuel efficiency and CO2 emissions of combination tractors vary depending on the
configuration of the tractor. Many aspects of the tractor impact its performance, including the
engine fuel map (independent of improvements measured under the engine standard), the
transmission, drive axle, aerodynamics, and rolling resistance. For each tractor subcategory, the
agencies selected a theoretical tractor to represent the average 2017 model year tractor that meets
the Phase 1 standards (see 76 FR 57212, September 15, 2011). These tractors are used as
baselines from which to evaluate costs and effectiveness of additional technologies and
standards. The specific attributes of each tractor subcategory baseline are listed below in Table
2-25. Using these values, the agencies assessed the CO2 emissions and fuel consumption
performance of the baseline tractors using the final version of Phase 2 GEM. The results of these
simulations are shown below in Table 2-26.
The Phase 1 2017 model year tractor standards and the baseline 2017 model year tractor
results are not directly comparable. The same set of aerodynamic and tire rolling resistance
technologies were used in both setting the Phase 1 standards and determining the baseline of the
Phase 2 tractors. However, there are several aspects that differ. First, a new version of GEM
was developed and validated to provide additional capabilities, including more refined modeling
of transmissions and engines. Second, the determination of the HD Phase 2 CdA value takes into

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
account a revised test procedure, a new standard reference trailer, and wind averaged drag.
Additionally, the HD Phase 2 version of GEM includes road grade in the 55 mph and 65 mph
highway cycles, as discussed in Preamble Section III.E.
The agencies used the same adoption rates of tire rolling resistance for the Phase 2
baseline as we used to set the Phase 1 2017 MY standards. See 76 FR 57211. The tire rolling
resistance level assumed to meet the 2017 MY Phase 1 standard high roof sleeper cab is
considered to be a weighted average of 10 percent pre-Phase 1 baseline rolling resistance, 70
percent Level 1, and 20 percent Level 2. The tire rolling resistance to meet the 2017MY Phase 1
standards for the high roof day cab, low roof sleeper cab, and mid roof sleeper cab includes 30
percent pre-Phase 1 baseline level, 60 percent Level 1 and 10 percent Level 2. Finally, the low
and mid roof day cab 2017 MY standards were premised on a weighted average rolling
resistance consisting of 40 percent baseline, 50 percent Level 1, and 10 percent Level 2. The
agencies did not receive comments on the tire packages in the NPRM used to develop the Phase
2 baseline.
The Phase 2 baseline in the NPRM was determined based on the aerodynamic bin
adoption rates used to determine the Phase 1 MY 2017 tractor standards. The vehicles that were
tested prior to the NPRM were used to develop the proposed aerodynamic bin structure for Phase
2. In both the NPRM and this final rulemaking, we developed the Phase 2 bins such that there is
an alignment between the Phase 1 and Phase 2 aerodynamic bins after taking into consideration
the changes in aerodynamic test procedures and reference trailers required in Phase 2. The Phase
2 bins were developed so that tractors that performed as a Bin III in Phase 1 would also perform
as Bin III tractors in Phase 2. The baseline aerodynamic value for the Phase 2 final rulemaking
was determined in the same manner as the NPRM, using the adoption rates of the bins used to
determine the Phase 1 standards, but reflect the final Phase 2 bin CdA values.
The agencies determined the rear axle ratio and final drive ratio in the 2017 MY baseline
tractor based on axle market information shared by Meritor,124 one of the primary suppliers of
heavy-duty axles and confidential business information provided by Daimler. Our assessment of
this information found that a rear axle ratio of 3.70 and a top gear ratio of 0.73 (equivalent to a
final drive ratio of 2.70) is a commonly spec'd tractor. Meritor's white paper on downspeeding
stated that final drive ratios of less than 2.64 are considered to be "downsped."125 The agencies
recognize that there is a significant range in final drive ratios that will be utilized by tractors built
in 2017 MY, we do not believe that the average (i.e., baseline) tractor in 2017 MY will
downsped.
In the proposal, the agencies noted that the manufacturers were not using tamper-proof
automatic engine shutdown systems (AESS) to comply with the Phase 1 standards. As a result
the agencies reverted back to the baseline auxiliary power unit (APU) adoption rate of 30 percent
used in the Phase 1 baseline. In response to comments, the agencies reassessed the baseline idle
reduction adoption rates. The latest NACFE confidence report found that 9 percent of tractors
had auxiliary power units and 96 percent of vehicles are equipped with adjustable automatic
engine shutdown systems.126 Therefore, the agencies are projecting that 9 percent of sleeper
cabs will contain an adjustable AESS and APU, while the other 87 percent will only have an
adjustable AESS.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-25 GEM Inputs for the 2017 Baseline Class 7 and 8 Tractors
CLASS 7
CLASS 8
Day Cab
Day Cab
Sleeper Cab
Low
Mid Roof
High Roof
Low Roof
Mid Roof
High Roof
Low Roof
Mid Roof
High
Roof







Roof
Engine
2017 MY
2017 MY
2017 MY
2017 MY
2017 MY
2017 MY
2017 MY
2017 MY
2017
11L
11L
11L
15L
15L
15L
15L
15L Engine
MY
Engine
Engine
Engine
Engine
Engine
Engine
Engine
455 HP
15L
350 HP
350 HP
350 HP
455 HP
455 HP
455 HP
455 HP

Engine








455 HP
Aerodynamics (CdA in m2)
5.41
6.48
6.38


6.38


5.90



5.41
6.48

5.41
6.48

Steer Tires (CRR in kg/metric ton)
6.99
6.99
6.87
6.99
6.99
6.87
6.87
6.87
6.54
Drive Tires (CRR in kg/metric ton)
7.38
7.38
7.26
7.38
7.38
7.26
7.26
7.26
6.92
Extended Idle Reduction - Adjustable AESS with no Idle Red Tech Adoption Rate @ 1% Effectiveness
N/A
N/A
N/A
N/A
N/A
N/A
87%
87%
87%
Extended Idle Reduction - Adjustable AESS with Diesel APU Adoption Rate @
3% Effectiveness
N/A
N/A
N/A
N/A
N/A
N/A
9%
9%
9%


Transmission = 10 Speed Manual Transmission



Gear Ratios =
12.8, 9.25, 6.76, 4.90, 3.58, 2.61, 1.89, 1.38, 1.00, 0.73

Drive Axle Configuration = 4x2
Drive Axle Configuration = 6x4



Tire Revs/Mile =
= 512






Drive Axle Ratio
= 3.70



Table 2-26 Class 7 and 8 Tractor 2017 Baseline CO2 Emissions and Fuel Consumption

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
CO 2 (grams
CCh/ton-mile)
119.1
127.2
129.7
91.3
96.6
98.2
84.0
90.2
87.8
Fuel
Consumption
(gal/1,000 ton-
mile)
11.699
41
12.4950
9
12.7406
7
8.9685
7
9.4891
9
9.64637
8.25147
8.86051
8.62475
The 2017 model year baseline fuel maps in the HD Phase 2 version of GEM are different
than those used in 2017 year fuel maps in the HD Phase 1 version. The baseline map in the HD
Phase 2 version takes two major factors into consideration. The first is the likelihood of engine
down speeding beyond the 2020 model year and the second is making the gradient of brake

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
specific fuel consumption rate (BSFC) around the fuel consumption sweet spot less radical when
compared to the HD Phase 1 version's engine fuel map. All the baseline engine fuel maps for
use in 2017 can be seen in Chapter 2.7.5. All other maps from 2021 to 2027 can be seen in
Chapter 2.8.4.1.
The agencies received comments regarding the heavy-haul baseline vehicle with respect
to the transmission and axle ratio. Upon consideration of these comments, the agencies find that
the baseline heavy-haul tractor is better represented by an 18-speed transmission with a 3.73 rear
axle ratio. The heavy-haul tractor baseline configuration inputs to GEM for the Phase 2 final
rule are shown below in Table 2-27. The baseline 2017 MY heavy-haul tractor will emit 56.9
grams of CO2 per ton-mile and consume 5.59 gallons of fuel per 1,000 ton-mile.
Table 2-27 Heavy-Haul Tractor Baseline Configuration
BASELINE HEAVY-HAUL TRACTOR CONFIGURATION
Engine = 2017 MY 15L Engine with 600 HP
	Aerodynamics (CdA in m2) = 5.00	
Steer Tires (CRR in kg/metric ton) = 7.0
Drive Tires (CRR in kg/metric ton) = 7.4
Transmission = 18 speed Manual Transmission
Gear ratio= 14.4, 12.29, 8.51, 7.26, 6.05, 5.16, 4.38, 3.74, 3.2, 2.73, 2.28, 1.94,
	1.62, 1.38, 1.17, 1.00,0.86,0.73	
Drive axle Ratio = 3.73
All Technology Improvement Factors = 0%
2.8.2 Defining the Tractor Technology Packages
The agencies' assessment of the technology effectiveness was developed through the use
of GEM in coordination with modeling conducted by Southwest Research Institute. The
agencies developed the standards through a three-step process, similar to the approach used in
Phase 1. First, the agencies developed technology performance characteristics or effectiveness
for each technology, as described below. Each technology is associated with an input parameter
which in turn is used as an input to the Phase 2 GEM simulation tool (i.e. the final version of
GEM used both to develop standard stringency and to evaluate compliance at certification) and
its effectiveness thereby modeled. Second, the agencies combined the technology performance
levels with a projected technology adoption rate to determine the GEM inputs used (in step 3) to
set the stringency of the final standards. Third, the agencies input these parameters into Phase 2
GEM and used the output to determine the final CO2 emissions and fuel consumption levels. All
percentage improvements noted below are over the 2017 baseline tractor.
2.8.2.1 Engine
Please see RIA Chapter 2.7 for a discussion on engine technologies.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.8.2.2 Aerodynamics
The aerodynamic packages are categorized as Bin I, Bin II, Bin III, Bin IV, Bin V, Bin
VI, or Bin VII based on the wind averaged drag aerodynamic performance determined through
testing conducted by the manufacturer. In general, the CdA values for each package and tractor
subcategory were developed through EPA's coastdown testing of tractor-trailer combinations,
the 2010 NAS report, and SAE papers.127'128 The agencies also discuss aerodynamic
technologies for tractors in Chapter 2.4.1 of the RIA.
As noted in Section III.D of the Preamble, the agencies received comments from
manufacturers about the feasibility of developing tractors with aerodynamics that could achieve
the proposed Bins V and above. After the proposal, the agencies reviewed new information
regarding the aerodynamic improvements achieved in the SuperTruck program for high roof
sleeper cabs and box trailers. Also after the proposal, the truck manufacturers conducted CFD
analysis of a "typical Bin III" high roof sleeper cab tractor with a Phase 2 standard trailer (with a
trailer skirt), a SuperTruck tractor with a Phase 2 standard trailer, and a SuperTruck tractor with
a SuperTruck trailer. Even though the agencies did not conduct the CFD testing, we agree with
the methodology and the results. As shown in Figure 2-22, the difference between a Bin III high
roof sleeper cab tractor and a SuperTruck tractor, both with a Phase 2 standard trailer, is
approximately 1.0 m2 As shown in Table 2-28, the CdA difference between Bin III and Bin IV
is approximately 0.5 m2 and the difference between Bin III and Bin V is approximately 1.0 m2
Therefore, a SuperTruck tractor would be able to achieve a Bin V level in Phase 2 with the Phase
2 standard trailer.
Table 2-28 Phase 2 Aerodynamic Bin Values for High Roof Sleeper
PHASE 2 AERO BINS FOR HIGH
ROOF SLEEPER CABS
Phase 2 Bin
CdA Range (m2)
Bin III
5.7-6.2
Bin IV
5.2-5.6
Bin V
4.7-5.1

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Aero Stringency
ifcioecy Magfrtude [m-'wc]

BIN V (4.7
-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review **"*
The effectiveness of aerodynamic improvements depends on the drive cycle. As shown
below in Figure 2-23, aerodynamics on sleeper cabs that operate a higher fraction of their miles
at highway speeds have a greater impact on fuel consumption and CO2 emissions.
Aerodynamic Impact on Tractor Fuel Consumption
Sleeper Cab
Figure 2-23 Aerodynamic Impact on Tractor CO2 Emissions based on Phase 2 GEM Simulations
2.8.2.3 Tire Rolling Resistance
The rolling resistance coefficient target for the Phase 2 NPRM was developed from
SmartWay's tire testing to develop the SmartWay certification and testing a selection of tractor
tires as part of the Phase 1 and Phase 2 programs. Even though the coefficient of tire rolling
resistance comes in a range of values, to analyze this range, the tire performance was evaluated
at four levels for both steer and drive tires, as determined by the agencies. The four levels in the
Phase 2 proposal included the baseline (average) from 2010, Level I and Level 2 from Phase 1,
and Level 3 that achieves an additional 25 percent improvement over Level 2. The Level 1
rolling resistance performance represents the threshold used to develop SmartWay designated
tires for long haul tractors. The Level 2 threshold represents an incremental step for
improvements beyond today's SmartWay level and represents the best in class rolling resistance
of the tires we tested for Phase 1. The Level 3 values in the NPRM represented the long-term
rolling resistance value that the agencies predicts could be achieved in the 2025 timeframe.
Given the multiple year phase-in of the standards, the agencies expect that tire manufacturers
will continue to respond to demand for more efficient tires and will offer increasing numbers of
tire models with rolling resistance values significantly better than today's typical low rolling
resistance tires.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
ICCT found in their workshop that opportunities exist for improvements in rolling
resistance for tractor tires that could lead to a two to six percent improvement in fuel
consumption when compared to a 2010 baseline tractor.130 A fuel consumption improvement in
this range would require a six to 18 percent improvement in the tractor tire rolling resistance
levels. Michelin commented that the proposed values for the drive tires seem reasonable, though
the 4.5 kg/ton level would require significantly higher adoption rate of new generation wide base
single tires. Michelin also stated that the value of 4.3 kg/ton target for steer tires is highly
unlikely based on current evolution and that research shows that 5.0 kg/ton would be more
likely.
The agencies have evaluated this comment and find it persuasive. The agencies analyzed
the 2014MY certification data for tractors between the NPRM and final rulemaking. We found
that the lowest rolling resistance value submitted for 2014 MY GHG and fuel efficiency
certification for tractors was 4.9 and 5.1 kg/metric ton for the steer and drive tires respectively,
while the highest rolling resistance tire had a CRR of 9.8 kg/metric ton.131 We have accordingly
increased the coefficient of rolling resistance for Level 3 tires in the final rule based on the
comments and the certification data.
Figure 2-24 shows the impact of changing the rolling resistance on CO2 emissions and
fuel consumption of tractors.
Rolling Resistance Impact on Tractor Fuel Consumption
4.0%
Sleeper Cab
u
-3.0%
Tractor-Trailer Weighted CRR (kg/metric ton)
Figure 2-24 Impact of the Coefficient of Rolling Resistance (CRR) on Fuel Consumption based on Phase 2
GEM Simulations

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.8.2.4	Tire Pressure Monitoring and Automatic Tire Inflation Systems
As noted in RIA Chapter 2.4.3.3, automatic tire inflation systems (ATIS) provide fuel
consumption improvement opportunities because they keep the tires at the proper inflation
pressure. Tire pressure monitoring systems (TPMS) notify the operator of tire pressure, but
require the operator to manually inflate the tires to the optimum pressure. The agencies did not
propose to include TPMS as a GEM input because of this dependence on the operator. Instead,
we requested comment and sought data to support a reduction level. Many commenters
suggested that the agencies should recognize TPMS in GEM and provided some additional
studies.
After consideration of the comments, the agencies are adopting provisions in Phase 2 to
allow GEM inputs for either ATIS or TPMS. The agencies believe there is sufficient incentive
for truck operators to address low tire pressure conditions if they are notified that the condition
exists by TPMS.
The agencies considered the comments and the studies to determine the effectiveness of
TPMS and ATIS. ICCT found in their workshop that opportunities exist for ATIS that could
lead to a 0.5 to two percent improvement in fuel consumption.132 The agencies conducted a
further review of the FCMSA study cited by commenters and we interpret the results of the study
to indicate that overall a combination of TPMS and ATIS in the field achieved 1.4 percent
reduction. However, it did not separate the results from each technology, therefore it did not
indicate that TPMS and ATIS achieved the same levels of reduction. Therefore, we set the
effectiveness of TPMS slightly lower than ATIS to reflect that operators will be required to take
some action to insure that the proper inflation pressure is maintained. The input values to the
Phase 2 GEM are set to 1.2 percent reduction in CO2 emissions and fuel consumption for ATIS
and 1.0 percent reduction for TPMS.
2.8.2.5	Idle Reduction
The benefits for the extended idle reductions were developed from literature, SmartWay
work, and the 2010 NAS report. Additional details regarding the comments and calculations are
included in RIA Chapter 2.4.8.1.
2.8.2.6	Transmission
The benefits for automated manual (AMT) and automatic (AT) transmissions were
developed from literature, from simulation modeling conducted by Southwest Research Institute,
and powertrain testing at Oak Ridge National Laboratory. The agencies' assessment of the
comments is that Allison, ICCT, and Volvo support the proposed two percent effectiveness for
AT and AMT transmission types. In addition, the agencies reviewed the NACFE report on
electronically controlled transmissions (AT, AMT, and DCT).133 This report had similar
findings as those noted above in the NAS 2010 report. Electronically controlled transmissions
were found to be more fuel efficient than manual transmissions, though the amount varied
significantly. The report also stated that fleets found that electronically controlled transmissions
also reduced the fuel efficiency variability between drivers. Therefore after considering the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
comments related to effectiveness and additional reports, the agencies are adopting as proposed a
two percent effectiveness for AMT.
The agencies conducted powertrain testing at Oak Ridge National Laboratory using the
same HD diesel engine paired with an Eaton AMT and an Allison TC10 AT to evaluate the
impact of the transmission type on the CO2 emissions and fuel consumption.134 The Allison
TC10 transmission is their newest and most efficient heavy-duty automatic transmission and
contains the neutral-idle and first gear lock-up features. The agencies swept final drive ratio
during the testing to recognize that the proper spec'ing of the rear axle ratio will vary depending
on the type of transmission and the top gear ratio of the transmission. As shown in Figure 2-25
and Figure 2-26, the fuel consumption over the highway cycles simulating a Class 8 tractor-
trailer was similar between the two transmissions. Figure 2-27 shows that the TC10 automatic
transmission had lower fuel consumption over the transient cycle, but because the drive cycle
weighting of the ARB transient cycle is low in tractors, the agencies expect that automatic
transmissions designed for long haul operation and automated manual transmissions to perform
similarly and have similar effectiveness when compared to a manual transmission.
The benefit of the AMT's automatic shifting compared to a manual transmission is
recognized in GEM by simulating the MT as an AMT and increasing the emission results from
the simulation by two percent. For ATs, the agencies developed the default automatic
transmission inputs to GEM to represent a typical heavy-duty automatic transmission, which is
less efficient than the TC10. The agencies selected more conservative default transmission
losses in GEM so that we would not provide a false efficiency improvement for the less efficient
automatic transmissions that exist in the market today. Under the regulations in this rulemaking,
manufacturers that certify using the TC10 transmission would need to either conduct the optional
transmission gear efficiency testing or powertrain testing to recognize the benefits of this type of
automatic transmission in GEM. However, as noted in Section II.C.5 of the FRM Preamble, the
agencies could determine in a future action that it would be appropriate to modify GEM to be
equivalent to powertrain testing technology, rather than to require manufacturers to perform
powertrain testing to be credited for the full benefits of technologies such as advanced
transmissions. In such a case, the agencies would not consider the modification to GEM to
impact the effective stringency of the Phase 2 standards because the new version of GEM would
be equivalent to performing powertrain testing. Thus, we encourage manufacturers to work with
us in the coming years to investigate the potential to streamline the process for fully recognizing
advanced transmissions in GEM.

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review

590
JE
580
ap
570
_oj
560
o

u
550
s_
(D
540
>

O
530
~o

TC10
>AMT
2.5
3.5
Final Drive Ratio
Figure 2-25 Powertrain Test Results of AMT and AT over the 65 mph Cycle
Powertrain Testing Results - 55 mph Cycle
/ion

ฃ 475
— 470
aj
u 465
s-
^ 460
(D
> 455
"S 450
| 445
to
c 440
!=! 435
aj
ฃ 430



•





















•
•

• TC10



• AMT
•
• -
* •






• *



I
2.5 3 3.5
Final Drive Ratio
Figure 2-26 Powertrain Test Results of AMT and AT over the 55 mph Cycle

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Powertrain Testing - ARB Transient Cycle

765
JE

ap
760
(D

O



U

i_
755
(D

>

O

~o
TC10
>AMT
2.5	3	3.5
Final Drive Ratio
Figure 2-27 Powertrain Test Results of AMT and AT over the Transient Cycle
2.8.2.6.1	Transmission Efficiency
The agencies also proposed standards that considered the efficiency benefit of
transmissions that operate with top gear direct drive instead of overdrive. In the proposal, we
estimated that direct drive had 2 percent higher gear efficiency than an overdrive gear. 80 FR
40229. The benefit of direct drive was recognized through the transmission gear ratio inputs to
GEM. Direct drive leads to greater CO2 emissions and fuel consumption reductions in highway
operation, but virtually none in transient operation. ICCT cited a finding that highlighted
opportunities to improve transmission efficiency, including direct drive, which would provide
about two percent fuel consumption reduction.135 The agencies did not receive any negative
comments regarding the efficiency difference between direct drive and overdrive; therefore, we
continued to include the default transmission gear efficiency advantage of 2 percent for a gear
with a direct drive ratio in the version of GEM adopted for the final Phase 2 rules.
The agencies are also adopting in Phase 2 an optional transmission efficiency test (40
CFR 1037.565) for generating an input to GEM that overrides the default efficiency of each gear
based on the results of the test. Although optional, the transmission efficiency test will allow
manufacturers to reduce the CO2 emissions and fuel consumption by designing better
transmissions with lower friction due to better gear design and/or mandatory use of better
lubricants. The agencies project that transmission efficiency could improve 1 percent over the
2017 baseline transmission in Phase 2. Our assessment was based on comments received and
discussions with transmission manufacturers.136
2.8.2.6.2	Neutral Idl e
Automatic transmissions historically apply torque to an engine when in gear at zero speed
because of torque converter, such as when stopped at a traffic light. A neutral idle technology
can disengage transmission with torque converter, thus reducing power loss to a minimum. The

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
agencies simulated the impact of reducing the load on the engine at idle in GEM for tractors. As
expected, neutral idle had zero impact on the highway cycles because those cycles do not include
any idle time. During the ARB Transient cycle, neutral idle reduced CO2 emissions and fuel
consumption by 3.8 percent. The composite impact of neutral idle on CO2 emissions and fuel
consumption for day cabs is 1.2 percent and is 0.3 percent for sleeper cabs.
2.8.2.7 Drivetrain and Engine Downspeeding
Axle Configurations: Please see RIA Chapter 2.4.5.3 for the discussion on axle
configurations.
The agencies' assessments of these technologies show that the reductions are in the range
of 2 to 3 percent. For the final rule, the agencies are simulating 6x2, 4x2, and disengageable
axles within GEM instead of providing a fixed value for the reduction. This approach is more
technically sound because it will take into account future changes in axle efficiency. Tractor
simulations using Phase 2 GEM indicated that 6x4 and 4x2 axle configurations lead to a 2
percent improvement in day cab and sleeper cab tractor efficiency.
Downspeeding: Downspeeding would be as demonstrated through the Phase 2 GEM
inputs of transmission gear ratio, drive axle ratio, and tire diameter. Volvo offers an XE package
for fuel efficiency in 2017 MY that includes a downspeed package with a 2.64 rear axle ratio and
0.78 top transmission gear ratio, equivalent to a 2.06 final drive ratio (FDR). The agencies
evaluated the impact of downspeeding during a powertrain test of a heavy HD diesel engine and
automated manual transmission while simulating a Class 8 tractor-trailer.137 The results are
shown in Figure 2-28. Downspeeding from a 2.6 FDR to a 2.3 FDR reduced fuel consumption
by 2.5 percent.
540
535
oT 530
~! 525
"S 520
ฃ
3 515
ฃ
8 510
"ai
j? 505
500
495
1.
Final Drive Ratio Impact on Composite Fuel Consumption
Powertrain Test Results













































































.1
.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9 3.
Final Drive Ratio
Figure 2-28 Downspeeding Impact on Fuel Consumption

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Axle Efficiency: Please see RIA Chapter 2.4.5.1 for additional discussion on
opportunities to improve axle efficiency. The 2010 NAS report assessed low friction lubricants
for the drivetrain as providing a 1 percent improvement in fuel consumption based on fleet
testing.138 The light-duty 2012-16 MY vehicle rule and the pickup truck portion of this program
estimate that low friction lubricants can have an effectiveness value between 0 and 1 percent
compared to traditional lubricants. In the Phase 2 proposal, the agencies proposed the reduction
in friction due to low viscosity axle lubricants of 0.5 percent. 80 FR 40217.
The agencies' assessment of axle improvements found that axles built in the Phase 2
timeline could be 2 percent more efficient than a 2017 baseline axle.139 In lieu of a fixed value
for low friction axle lubricants, the agencies are adopting an axle efficiency test procedure (40
CFR 1037.560), as discussed in the NPRM. 80 FR 40185. The axle efficiency test will be
optional, but will allow manufacturers to recognize in GEM reductions in CO2 emissions and
fuel consumption through improved axle gear designs and/or mandatory use of low friction
lubricants.
2.8.2.8 Accessories and Other Technologies
Reducing the mechanical and electrical loads of accessories reduce the power
requirement of the engine and in turn reduces the fuel consumption and CO2 emissions.
Modeling in GEM, as shown in Table 2-29, demonstrates the impact of reducing 1 kW of
accessory load for each tractor subcategory.
Table 2-29 Impact of 1 kW Accessory Load Reduction on CO2 Emissions

Tractor Subcategory
%C02 per kW
Class 8 High Roof Sleeper
0.5%
Class 8 Mid Roof Sleeper
0.5%
Class 8 Low Roof Sleeper
0.6%
Class 8 High Roof Day
0.6%
Class 8 Mid Roof Day
0.6%
Class 8 Low Roof Day
0.7%
Class 7 High Roof Day
0.8%
Class 7 Mid Roof Day
0.8%
Class 7 Low Roof Day
0.8%
Heavy Haul
0.5%
Compared to 2017 MY air conditioners, air conditioners with improved efficiency
compressors could reduce CO2 emissions by 0.5 percent. Improvements in accessories, such as
power steering, can lead to an efficiency improvement of 1 percent over the 2017MY baseline
(also see RIA Chapter 2.4.10). The agencies received several comments related to accessories.
Due to the complexity in determining a definition of that qualifies as an efficient accessory, we
are maintaining the proposed language for tractor accessories which provides defined
effectiveness values only for electric or high efficiency air conditioning compressors, electric

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
power steering pumps, and electric coolant pumps (if not already accounted for during the engine
fuel mapping procedure).
The agencies proposed to provide a two percent reduction for intelligent controls, such
as predictive cruise. Control. ICCT found in their workshop that opportunities exist for road
load optimization through predictive cruise, GPS, and driver feedback that could lead to a zero to
five percent reduction in fuel consumption and CO2 emissions.140 Daimler commented that
eCoast should also be recognized as an intelligent control within GEM. Eaton offers similar
technology, known as Neutral Coast Mode. The feature places an automated transmission in
neutral on downhill grades which allows the engine speed to go idle speed. A fuel savings is
recognized due to the difference in engine operating conditions. Based on literature information,
the agencies are adopting intelligent controls such as predictive cruise control with an
effectiveness of two percent (also see RIA Chapter 2.4.11) and neutral coasting with an
effectiveness of 1.5 percent.
2.8.2.9	Weight Reduction
The weight reductions were developed from tire manufacturer information, the
Aluminum Association, the Department of Energy, SABIC and TIAX. The fuel consumption
and CO2 emissions impact of a 1,000 pound weight reduction on tractors is approximately 1.2 to
1.5 percent based on simulations conducted in Phase 2 GEM. This reduction includes the impact
of both reducing the overall weight of the vehicle for the fraction of the fleet that is cubed-out
and the increase in payload capability for the fraction of the fleet that is weighed-out.
2.8.2.10	Vehicle Speed Limiter
The agencies did not include vehicle speed limiters in setting the Phase 1 stringency
levels. The agencies likewise are not including vehicle speed limiters in the technology package
for setting the standards for Class 7 and 8 tractors in Phase 2. The effectiveness of VSLs depend
on the type of tractor because it is dependent on the drive cycle. The greater the amount of time
spent at 65 mph, the greater the impact of a VSL set below 65 mph. Figure 2-29 shows the
effectiveness of VSL on sleeper and day cab tractors based on modeling conducted using Phase 2
GEM.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
12.0%
C
o
O
-g 10.0%
(D
C
ฃ 8.0%
Q.
E
3
c
o
u
(D
3
ฆa
c
c
o
f\J
O
U
6.0%
4.0%
2.0%
0.0%
54
Vehicle Speed Limiter Effectiveness
Composite Result
-Sleeper Cab
ฆ Day Cab
58	60	62
Vehicle Speed Limiter Setting (mph)
66
Figure 2-29 Vehicle Speed Limiter Impact on Tractor Fuel Consumption
2.8.2.11 Consideration of Phase 1 Credits in Phase 2 Stringency Setting
The agencies requested comment regarding the treatment of Phase 1 credits, as discussed
in Section I.C. 1 .b. See 80 FR 40251. As examples, the agencies discussed limiting the use of
Phase 1 credits in Phase 2 and factoring credit balances into the 2021 standards. Daimler
commented that allowing Phase 1 credits in Phase 2 is necessary to smooth the transition into a
new program that is very complex and that HD manufacturers cannot change over an entire
product portfolio at one time. The agencies evaluated the status of Phase 1 credit balances in
2015 by sector. For tractors, we found that manufacturers are generating significant credits, and
that it appears that many of the credits result from their use of an optional provision for
calculating aerodynamic drag. However, we also believe that manufacturers will generate fewer
credits in MY 2017 and later when the final Phase 1 standards begin. Still, the agencies believe
that manufacturers will have significant credits balances available to them for MYs 2021-2023,
and that much of these balances would be the result of the test procedure provisions rather than
pull ahead of any technology. Based on confidential product plans for MYs 2017 and later, we
expect this total windfall amount to be three percent of the MY 2021 standards or more.
Therefore, the agencies are factoring in a total credit amount equivalent to this three percent
credit (i.e. three years times 1 percent per year). Thus, we are increasing the stringency of the
CO2 and fuel consumption tractor standards for MYs 2021-2023 by 1 percent to reflect these
credits.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.8.2.12 Summary of Technology Performance
Table 2-30 describes the performance levels for the range of Class 7 and 8 tractor
technologies.
Table 2-30 Phase 2 Technology Inputs for Tractors

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
Engine

2021MY
11L
Engine
350 HP
2021MY
11L
Engine
350 HP
2021MY
11L
Engine
350 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
Aerodynamics (Cd A in m2)
Bin I
6.00
7.00
7.45
6.00
7.00
7.45
6.00
7.00
7.15
Bin II
5.60
6.65
6.85
5.60
6.65
6.85
5.60
6.65
6.55
Bin III
5.15
6.25
6.25
5.15
6.25
6.25
5.15
6.25
5.95
Bin IV
4.75
5.85
5.70
4.75
5.85
5.70
4.75
5.85
5.40
Bin V
4.40
5.50
5.20
4.40
5.50
5.20
4.40
5.50
4.90
Bin VI
4.10
5.20
4.70
4.10
5.20
4.70
4.10
5.20
4.40
Bin VII
3.80
4.90
4.20
3.80
4.90
4.20
3.80
4.90
3.90
Steer Tires (CRR in kg/metric ton)
Base
7.8
7.8
7.8
7.8
7.8
7.8
7.8
7.8
7.8
Level 1
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
Level 2
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
Level 3
4.9
4.9
4.9
4.9
4.9
4.9
4.9
4.9
4.9
Drive Tires (CRR in kg/metric ton)
Base
8.1
8.1
8.1
8.1
8.1
8.1
8.1
8.1
8.1
Level 1
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
Level 2
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
Level 3
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
Idle Reduction (% reduction)
Tamper
Proof AESS
N/A
N/A
N/A
N/A
N/A
N/A
4%
4%
4%
Tamper
Proof AESS
with Diesel
APU
N/A
N/A
N/A
N/A
N/A
N/A
4%
4%
4%
Tamper
Proof AESS
with Battery
APU
N/A
N/A
N/A
N/A
N/A
N/A
6%
6%
6%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Tamper
Proof AESS
with
Automatic
Stop-Start
N/A
N/A
N/A
N/A
N/A
N/A
3%
3%
3%
Tamper
Proof AESS
with FOH
N/A
N/A
N/A
N/A
N/A
N/A
3%
3%
3%
Adjustable
AESS
N/A
N/A
N/A
N/A
N/A
N/A
1%
1%
1%
Adjustable
AESS with
Diesel APU
N/A
N/A
N/A
N/A
N/A
N/A
3%
3%
3%
Adjustable
AESS with
Battery
APU
N/A
N/A
N/A
N/A
N/A
N/A
5%
5%
5%
Adjustable
AESS with
Automatic
Stop-Start
N/A
N/A
N/A
N/A
N/A
N/A
5%
5%
5%
Adjustable
AESS with
FOH
N/A
N/A
N/A
N/A
N/A
N/A
2%
2%
2%
Transmission (% reduction)
Manual
0%
0%
0%
0%
0%
0%
0%
0%
0%
AMT
2%
2%
2%
2%
2%
2%
2%
2%
2%
Auto
2%
2%
2%
2%
2%
2%
2%
2%
2%
Dual Clutch
2%
2%
2%
2%
2%
2%
2%
2%
2%
Top Gear
Direct Drive
2%
2%
2%
2%
2%
2%
2%
2%
2%
Transmissio
n Efficiency
Improvemen
ts
1%
1%
1%
1%
1%
1%
1%
1%
1%
Neutral Idle
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Driveline (% reduction)
Axle
Efficiency
Improvemen
ts
2%
2%
2%
2%
2%
2%
2%
2%
2%
6x2, 6x4
Axle
Disconnect
or 4x2 Axle
N/A
N/A
N/A
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Downspeed
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Modeled
in GEM
Accessory Improvements (% reduction)
A/C
Efficiency
0.5%
0.5%
0.5%
0.5%
0.5%
0.5%
0.5%
0.5%
0.5%
Electric
Access.
1%
1%
1%
1%
1%
1%
1%
1%
1%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Other Technologies (% reduction)
Predictive
Cruise
Control
2%
2%
2%
2%
2%
2%
2%
2%
2%
Automated
Tire
Inflation
System
1.2%
1.2%
1.2%
1.2%
1.2%
1.2%
1.2%
1.2%
1.2%
Tire
Pressure
Monitoring
System
1%
1%
1%
1%
1%
1%
1%
1%
1%
Neutral
Coast
1.5%
1.5%
1.5%
1.5%
1.5%
1.5%
1.5%
1.5%
1.5%
2.8.3 Tractor Technology Adoption Rates
Often tractor manufacturers introduce major product changes together, as a package.
This allows manufacturers to optimize their available resources, including engineering,
development, manufacturing and marketing activities to create a product with multiple new
features. In some limited cases, manufacturers may implement an individual technology outside
of a vehicle's redesign cycle. It is recognized by the manufacturers that a vehicle design will
need to remain competitive over the intended life of the design and meet future regulatory
requirements.
With respect to the levels of technology adoption used to develop the HD Phase 2
standards, NHTSA and EPA established two types of technology adoption constraints. The first
type of constraint was established based on the application of fuel consumption and CO2
emission reduction technologies into the different types of tractors. For example, extended idle
reduction technologies are limited to Class 8 sleeper cabs based on the (reasonable) assumption
that day cabs are not used for overnight hoteling.
A second type of constraint was applied to most other technologies and limited their
adoption based on factors reflecting the real world operating conditions that some combination
tractors encounter. This second type of constraint was applied to the aerodynamic, tire,
powertrain, vehicle speed limiter, and other technologies. Table 2-34,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-35 and Table 2-36 specify the adoption rates that EPA and NHTSA used to
develop the final Phase 2 standards
NHTSA and EPA believe that within each of these individual vehicle categories there are
particular applications where the use of the identified technologies would be either ineffective or
not technically feasible. The addition of ineffective technologies provides no environmental or
fuel efficiency benefit, increases costs and is not a basis upon which to set a maximum feasible
improvement under 49 USC Section 32902 (k), or appropriate under 42 U.S.C. Section 7521
(a)(2). For example, the agencies are not predicating the standards on the use of full
aerodynamic vehicle treatments on 100 percent of tractors, because we know that in many
applications (for example gravel truck engaged in local aggregate delivery) the added weight of
the aerodynamic technologies would increase fuel consumption and hence CO2 emissions to a
greater degree than the reductions from the aerodynamic technology. .
Discussions related to our responses to comments received on technology adoption rates
for each of the technologies are included in Preamble Section III.D.l.c and in Section 4.3 of the
response to comments document. The sections below contain the final decisions based on the
consideration of these comments and any new data or information.
2.8.3.1 Aerodynamics Adoption Rate
The impact of aerodynamics on a tractor-trailer's efficiency increases with vehicle speed.
Therefore, the usage pattern of the vehicle will determine the benefit of various aerodynamic
technologies. Sleeper cabs are often used in line haul applications and drive the majority of their
miles on the highway travelling at speeds greater than 55 mph. The industry has focused
aerodynamic technology development, including SmartWay tractors, on these types of trucks.
Therefore the most aggressive aerodynamic technologies are applied to this regulatory
subcategory. All of the major manufacturers today offer at least one SmartWay sleeper cab
tractor model, which is represented as Bin III aerodynamic performance. For the NPRM, the
agencies developed a technology package for 2027 MY that included the aerodynamic adoption
rates shown in Table 2-31. 80 FR 40227.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-31 Proposed Aerodynamic Bin Adoption Rates for 2027 MY Tractors

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
Low
Roof
Mid
Roof
High
Roof
Aerodynamics
Bin I
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin II
50%
50%
0%
50%
50%
0%
50%
50%
0%
Bin III
40%
40%
20%
40%
40%
20%
40%
40%
20%
Bin IV
10%
10%
20%
10%
10%
20%
10%
10%
20%
Bin V
N/A
N/A
35%
N/A
N/A
35%
N/A
N/A
35%
Bin VI
N/A
N/A
20%
N/A
N/A
20%
N/A
N/A
20%
Bin VII
N/A
N/A
5%
N/A
N/A
5%
N/A
N/A
5%
In Phase 1, the agencies determined the stringency of the tractor standards through the
use of a mix of aerodynamic bins in the technology packages. For example, we included 10
percent Bin II, 70 percent Bin III, and 20 percent Bin IV in the high roof sleeper cab tractor
standard. The weighted average aerodynamic performance of this technology package is
equivalent to Bin III. 76 FR 57211. In consideration of the comments, the agencies have
adjusted the aerodynamic adoption rate for Class 8 high roof sleeper cabs used to set the final
standards in 2021, 2024, and 2027 MYs {i.e., the degree of technology adoption on which the
stringency of the standard is premised). Upon further analysis of simulation modeling of a
SuperTruck tractor with a Phase 2 reference trailer with skirts, we agree with the manufacturers
that a SuperTruck tractor technology package would only achieve the Bin V level of CdA, as
discussed above in RIA Chapter 2.8.2.2. Consequently, the final standards are not premised on
any adoption of Bin VI and VII technologies. Accordingly, we determined the adoption rates in
the technology packages developed for the final rule using a similar approach as Phase 1 -
spanning three aerodynamic bins and not setting adoption rates in the most aerodynamic bin(s) -
to reflect that there are some vehicles whose operation limits the applicability of some
aerodynamic technologies. We set the MY 2027 high roof sleeper cab tractor standards using a
technology package that included 20 percent of Bin III, 30 percent Bin IV, and 50 percent Bin V
reflecting our assessment of the fraction of high roof sleeper cab tractors that we project could
successfully apply these aerodynamic packages with this amount of lead time. The weighted
average of this set of adoption rates is equivalent to a tractor aerodynamic performance near the
border between Bin IV and Bin V. We believe that there is sufficient lead time to develop
aerodynamic tractors that can move the entire high roof sleeper cab aerodynamic performance to
be as good as or better than today's SmartWay designated tractors.
The agencies phased-in the aerodynamic technology adoption rates within the technology
packages used to determine the MY 2021 and 2024 standards so that manufacturers can
gradually introduce these technologies. The changes required for Bin V performance reflect the
kinds of improvements projected in the Department of Energy's SuperTruck program. That
program has demonstrated tractor-trailers in 2015 with significant aerodynamic technologies.
For the final rule, the agencies are projecting that truck manufacturers will be able to begin
implementing some of these aerodynamic technologies on high roof tractors as early as 2021 MY
on a limited scale. For example, in the 2021 MY technology package, the agencies have

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
assumed that 10 percent of high roof sleeper cabs will have aerodynamics better than today's
best tractors. This phase-in structure is consistent with the normal manner in which
manufacturers introduce new technology to manage limited research and development budgets as
well as to allow them to work with fleets to fully evaluate in-use reliability before a technology
is applied fleet-wide. The agencies believe the phase-in schedule will allow manufacturers to
complete these normal processes. Overall, while the agencies are now projecting slightly less
benefit from aerodynamic improvements than we did in the NPRM, the actual aerodynamic
technologies being projected are very similar to what was projected at the time of NPRM
(however, these vehicles fall into Bin V in the final rule, instead of Bin VI and VII in the
NPRM). Importantly, our averaging, banking and trading provisions provide manufacturers with
the flexibility (and incentive) to implement these technologies over time even though the
standard changes in a single step.
The agencies also received comment regarding our aerodynamic assessment of the other
tractor subcategories. Aerodynamic improvements through new tractor designs and the
development of new aerodynamic components is an inherently slow and iterative process. The
agencies recognize that there are tractor applications that require on/off-road capability and other
truck functions which restrict the type of aerodynamic equipment applicable. We also recognize
that these types of trucks spend less time at highway speeds where aerodynamic technologies
have the greatest benefit. The 2002 VIUS data ranks trucks by major use.141 The heavy trucks
usage indicates that up to 35 percent of the trucks may be used in on/off-road applications or
heavier applications. The uses include construction (16 percent), agriculture (12 percent), waste
management (5 percent), and mining (2 percent). Therefore, the agencies analyzed the
technologies to evaluate the potential restrictions that will prevent 100 percent adoption of more
advanced aerodynamic technologies for all of the tractor regulatory subcategories and developed
standards with new penetration rates reflecting that these vehicles spend less time at highway
speeds. For the final rule, the agencies evaluated the certification data to assess how the
aerodynamic performance of high roof day cabs compare to high roof sleeper cabs. In 2014, the
high roof day cabs on average are certified to one bin lower than the high roof sleeper cabs.142
Consistent with the public comments, and the certification data, the aerodynamic adoption rates
used to develop the final Phase 2 standards for the high roof day cab regulatory subcategories are
less aggressive than for the Class 8 sleeper cab high roof tractors. In addition, the agencies are
also accordingly reducing the adoption rates in the highest bins for low and mid roof tractors to
follow the changes made to the high roof subcategories because we neither proposed nor expect
the aerodynamics of a low or mid roof tractor to be better than a high roof tractor.
2.8.3.2 Low Rolling Resistance Tire Adoption Rate
For the tire manufacturers to further reduce tire rolling resistance, the manufacturers must
consider several performance criteria that affect tire selection. The characteristics of a tire also
influence durability, traction control, vehicle handling, comfort, and retreadability. Tire design
requires balancing performance, since changes in design may change different performance
characteristics in opposing directions. A single performance parameter can easily be enhanced,
but an optimal balance of all the criteria would require improvements in materials and tread
design at a higher cost, as estimated by the agencies.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
For the final rulemaking, the agencies evaluated the tire rolling resistance levels in the
Phase 1 certification data.143 We found that high roof sleeper cabs are certified today with steer
tire rolling resistance levels that ranged between 4.9 and 7.6 kg/ton and with drive tires ranging
between 5.1 and 9.8 kg/ton. In the same analysis, we found that high roof day cabs are certified
with rolling resistance levels ranging between 4.9 and 9.0 kg/ton for steer tires and between 5.1
and 9.8 kg/ton for drive tires. This range spans the baseline through Level 3 rolling resistance
performance levels. Therefore, for the final rule we took an approach similar to the one taken in
Phase 1 and proposed in Phase 2 that considers adoption rates across a wide range of tire rolling
resistance levels to recognize that operators may have different needs. 76 FR 57211 and 80 FR
40227.
In our analysis of the Phase 1 certification data, we found that the drive tires on low and
mid roof sleeper cab tractors on average had 10 to 17 percent higher rolling resistance than the
high roof sleeper cabs. But we found only a minor difference in rolling resistance of the steer
tires between the tractor subcategories. Based on comments received and further consideration
of our own analysis of the difference in tire rolling resistance levels that exist today in the
certification data, the agencies are adopting Phase 2 standards using a technology pathway that
utilizes higher rolling resistance levels for low and mid roof tractors than the levels used to set
the high roof tractor standards. This is also consistent with the approach that we took in setting
the Phase 1 tractor standards. 76 FR 57211. In addition, the final rule reflects a reduction in
Level 3 adoption rates for low and mid roof tractors from 25 percent in MY 2027 used at
proposal (80 FR 40227) to zero percent adoption rate. The technology packages developed for
the low and mid roof tractors used to determine the stringency of the MY 2027 standards in the
final rule do not include any adoption rate of Level 3 drive tires to recognize the special needs of
these applications, consistent with the comments noted above raising concerns about applications
that limit the use of low rolling resistance tires.
The agencies phased-in the low rolling resistance tire adoption rates within the
technology packages used to determine the MY 2021 and 2024 standards so that manufacturers
can gradually introduce these technologies. In addition, the levels of rolling resistance used in
all of the technology packages are achievable with either dual or wide based single tires, so the
agencies are not forcing one technology over another. See Table 2-34 through Table 2-36 for the
adoption rates of each tractor subcategory.
2.8.3.3 Tire Pressure Monitoring System and Automatic Tire Inflation System
Adoption Rates
The agencies used a 20 percent adoption rate of ATIS in MY 2021 and a 40 percent
adoption rate in setting the proposed Phase 2 MY 2024 and 2027 tractor standards. 80 FR
40227.
The agencies received a number of comments on ATIS and TPMS. The agencies find the
comments related to a greater acceptance of TPMS in the tractor market to be persuasive.
However, available information indicates that it is feasible to utilize either TPMS or ATIS to
reduce the prevalence on underinflated tires in-use on all tractors. As a result, we are finalizing
tractor standards that are predicated on the performance of a mix of TPMS and ATIS adoption
rates in all tractor subcategories. The agencies are using adoption rates of 30 percent of ATIS

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
and 70 percent of TPMS in the technology packages used in setting the final Phase 2 MY 2027
tractor standards. This represents a lower adoption rate of ATIS than used in the NPRM, but the
agencies have added additional adoption rate of TPMS because none of the comments or
available information disputed the ability to use it on all tractors. The agencies have developed
technology packages for setting the 2021 and 2024 MY standards which reflect a phase in of
adoption rates of each of these technologies. In 2021 MY, the adoption rates consist of 20
percent TPMS and 20 percent ATIS. In 2024 MY, the adoption rates are 50 percent TPMS and
25 percent ATIS.
2.8.3.4	Weight Reduction Technology Adoption Rate
The agencies set the 2021 through 2027 model year tractor standards without using
weight reduction as a technology on whose performance the standard is predicated. The
agencies view weight reduction as a technology with a high cost that offers a small benefit in the
tractor sector. For example, our estimate of a 400 pound weight reduction would cost $2,050
(2012$) in MY2021, but offer a 0.3 percent reduction in fuel consumption and CO2 emissions.
Nonetheless, the agencies are adopting an expanded list of weight reduction options which could
be input into the GEM by the manufacturers to reduce their certified CO2 emission and fuel
consumption levels.
2.8.3.5	Idle Reduction Technology Adoption Rate
Idle reduction technologies provide significant reductions in fuel consumption and CO2
emissions for Class 8 sleeper cabs and are available on the market today. There are several
different technologies available to reduce idling. These include APUs, diesel fired heaters, and
battery powered units. Our discussions with manufacturers prior to the Phase 2 NPRM indicated
that idle technologies are sometimes installed in the factory, but that it is also a common practice
to have the units installed after the sale of the truck. We want to continue to incentivize this
practice and to do so in a manner that the emission reductions associated with idle reduction
technology occur in use. We proposed to continue the Phase 1 approach into Phase 2 where we
recognize only idle emission reduction technologies that include a tamper-proof automatic
engine shutoff system (AESS) with some override provisions.0
We used an overall 90 percent adoption rate of tamper-proof AESS for Class 8 sleeper
cabs in setting the proposed MY 2024 and 2027 standards. Id. The agencies stated in the Phase
2 NPRM that we were unaware of reasons why AESS with extended idle reduction technologies
could not be applied to this high fraction of tractors with a sleeper cab, except those deemed a
vocational tractor, in the available lead time.
The agencies received numerous comments on idle reduction adoption rates and the need
to consider adjustable AESS (see Section III.D.l.c.v of the Preamble). The agencies find the
comments regarding the concerns for using 90 percent adoption rates of tamper-proof AESS to
be persuasive. For the final rule, the agencies developed a menu of idle reduction technologies
that include both tamper-proof and adjustable AESS (as discussed in Section III.D.l.b) that are
G The agencies are retaining the HD Phase 1 AESS override provisions included in 40 CFR 1037.660(b) for driver
safety.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
recognized at different levels of effectiveness in GEM. As discussed in the discussion of tractor
baselines (Section III.D. 1 .a), the latest NACFE confidence report found that 96 percent of HD
vehicles are equipped with adjustable automatic engine shutdown systems.144 Therefore, the
agencies built this level of idle reduction into the baseline for sleeper cab tractors. Due to the
high percentage acceptance of adjustable AESS today, the agencies project that by 2027 MY it is
feasible for 100 percent of sleeper cabs to contain some type of AESS and idle reduction
technology to meet the hoteling needs of the driver. However, we recognize that there are a
variety of idle reduction technologies that meet the various needs of specific customers and not
all customers will select diesel powered APUs due to the cost or weight concerns highlighted in
the comments. Therefore, we developed an idle reduction technology package for each MY that
reflects this variety. The idle reduction packages developed for the final rule contain lower
AESS adoption rates than used at proposal. The AESS used during the NPRM assumed that it
also included a diesel powered APU in terms of determining the effectiveness and costs. In the
final rule, the idle reduction technology mix actually has an overall lower cost (even after
increasing the diesel APU technology cost for the final rule) than would have been developed for
the final rule. In addition, the stringency of the tractor standards are not affected because the
higher penetration rate of other idle reduction technologies, which are not quite as effective, but
will be deployed more. We developed the technology package to set the 2027 MY sleeper cab
tractor standards that includes 15 percent adoption rate of adjustable AESS only, 40 percent of
adjustable AESS with a diesel powered APU, 15 percent adjustable AESS with a battery APU,
15 percent adjustable AESS with automatic stop/start, and 15 percent adjustable AESS with a
fuel operated heater. We continued the same approach of phasing in different technology
packages for the 2021 and 2024 MY standards, though we included some type of idle reduction
on 100 percent of the sleeper cab tractors. The 2021 MY technology package had a higher
adoption rate of adjustable AESS with no other idle reduction technology and lower adoption
rates of adjustable AESS with other idle reduction technologies.
2.8.3.6 Transmission Adoption Rates
The agencies' proposed standards included a 55, 80, and 90 percent adoption rate of
automatic, automated manual, and dual clutch transmissions in MYs 2021, 2024, and 2027
respectively. 80 FR 40225-7. The agencies did not receive any comments regarding these
proposed transmission adoption rates, and have not found any other information suggesting a
change in approach. Therefore, we are including the same level of adoption rates in setting the
final rule standards. The MY 2021 and 2024 standards are likewise premised on the same
adoption rates of these transmission technologies as at proposal.
The agencies have added neutral idle as a technology input to GEM for Phase 2 in the
final rulemaking. The TC10 that was tested by the agencies for the final rule included this
technology. Therefore, we projected that neutral idle would be included in all of the automatic
transmissions and therefore the adoption rates of neutral idle match the adoption rates of the
automatic transmission in each of the MYs.
Transmissions with direct drive as the top gear and numerically lower axles are better
suited for applications with primarily highway driving with flat or low rolling hills. Therefore,
this technology is not appropriate for use in 100 percent of tractors. The agencies proposed
standards reflected the projection that 50 percent of the tractors would have direct drive in top

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
gear in MYs 2024 and 2027. 80 FR 40226-7. The agencies did not receive any comments
regarding the adoption rates of transmissions with direct drive in those MYs. We therefore are
including the same level of adoption rates in setting the final rule standards for MYs 2024 and
2027. Transmissions with direct drive top gears exist in the market today, therefore, the agencies
determined it is feasible to also include this technology in the package for setting the 2021 MY
standards. For the final rule, the agencies included a 20 percent adoption rate of direct drive in
the 2021 MY technology package.
The agencies received comments supporting establishing a transmission efficiency test
that measures the efficiency of each transmission gear and could be input into GEM. In the final
rule, the agencies are adopting Phase 2 standards that project that 20, 40, and 70 percent of the
AMT and DCT transmissions will be tested and achieve a fuel consumption and CO2 emissions
reduction of one percent in MYs 2021, 2024, and 2027, respectively.
2.8.3.7 Engine Downspeeding Adoption Rates
The agencies proposed to include lower final drive ratios in setting the Phase 2 standards
to account for engine downspeeding. In the NPRM, we used a transmission top gear ratio of
0.73 and baseline drive axle ratio of 3.70 in 2017 going down to a rear axle ratio of 3.55 in 2021
MY, 3.36 in 2024 MY, and 3.20 in 2027 MY. 80 FR 40228-30.
UCS commented that downspeeding was only partially captured as proposed. The
agencies also received additional information from vehicle manufacturers and axle
manufacturers that we believe supports using lower numerical drive axle ratios in setting the
final Phase 2 standards for sleeper cabs that spend more time on the highway than day cabs,
directionally consistent with the UCS comment. For the final rules, the agencies have used 3.70
in the baseline and 3.16 for sleeper cabs and 3.21 for day cabs in MY 2027 to account for
continued downspeeding opportunities. The final drive ratios used for setting the other model
years are shown in Table 2-32. These values represent the "average" tractor in each of the MYs,
but there will be a range of final drive ratios that contain more aggressive engine downspeeding
on some tractors and less aggressive on others.
Table 2-32 Final Drive Ratio for Tractor Technology Packages
MODEL
YEAR
REAR AXLE
RATIO
TRANSMISSION
TOP GEAR
RATIO
FINAL DRIVE
RATIO
Sleeper Cabs
2018
3.70
0.73
2.70
2021
3.31
0.73
2.42
2024
3.26
0.73
2.38
2027
3.16
0.73
2.31

Day Cabs
2018
3.70
0.73
2.70
2021
3.36
0.73
2.45
2024
3.31
0.73
2.42
2027
3.21
0.73
2.34

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.8.3.8 Drivetrain Adoption Rates
The agencies' proposed standards included 6x2 axle adoption rates in high roof tractors
of 20 percent in 2021 MY and 60 percent in MYs 2024 and 2027. Because 6x2 axle
configurations could raise concerns of traction, the agencies proposed standards that reflected
lower adoption rates of 6x2 axles in low and mid roof tractors recognizing that these tractors may
require some unique capabilities. The agencies proposed standards for low and mid roof tractors
that included 6x2 axle adoption rates of 10 percent in MY 2021 and 20 percent in MYs 2024 and
2027. 80 FR 40225-7.
ATA and others commented that limitations to a high penetration rate of 6x2 axles
include curb cuts, other uneven terrain features that could expose the truck to traction issues,
lower residual values, traction issues, driver dissatisfaction, tire wear, and the legality of their
use. Upon further consideration, the agencies have reduced the adoption rate of 6x2 axles and
projected a 30 percent adoption rate in the technology package used to determine the Phase 2
2027 MY standards. The 2021 MY standards include an adoption rate of 15 percent and the
2024 MY standards include an adoption rate of 25 percent 6x2 axles. This adoption rate
represents a combination of liftable 6x2 axles (which as noted in ATA's comments are allowed
in all states but Utah, and Utah is expected to revise their law) and 4x2 axles. In addition, it is
worth recognizing that state regulations related to 6x2 axles could change significantly over the
next ten years.
In the NPRM, the agencies projected that 20 percent of 2021 MY and 40 percent of the
2024 and 2027 MY axles would use low friction axle lubricants. 80 FR 40225-7. In the final
rule, we are requiring that manufacturers conduct an axle efficiency test if they want to include
the benefit of low friction lubricant or other axle design improvements when certifying in GEM.
The axle efficiency test will be optional, but will allow manufacturers to reduce CO2 emissions
and fuel consumption if the manufacturers have improved axle gear designs and/or mandatory
use of low friction lubricants. The agencies' assessment of axle improvements found that 80
percent of the axles built in MY 2027 could be two percent more efficient than a 2017 baseline
axle. Because it will take time for axle manufacturers to make improvements across the majority
of their product offerings, the agencies phased in the amount of axle efficiency improvements in
the technology packages in setting the 2021 and 2024 MY standards to include 30 and 65 percent
adoption rates, respectively.
2.8.3.9 Accessories and Other Technology Adoption Rates
In the NPRM, the agencies projected adoption rates as show in Table 2-33. 80 FR 40227.
The agencies are adopting the same level of adoption rates for setting the final Phase 2 standards
because we did not receive any comments or new data to support a change in the adoption rates
used in the proposal.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-33 Adoption Rates used in the Tractor Technology Packages in the NPRM
MODEL YEAR
PREDICTIVE
CRUISE
CONTROL
ELECTRIFIED
ACCESSORIES
HIGHER
EFFICIENCY AIR
CONDITIONING

2021
20%
10%
10%
2024
40%
20%
20%
2027
40%
30%
30%
2.8.3.10 Vehicle Speed Limiter Adoption Rate
As adopted in Phase 1, we are continuing the approach where vehicle speed limiters may
be used as a technology to aid in meeting the standard. In setting the standard, however, we
assumed a zero percent adoption rate of vehicle speed limiters. Although we believe vehicle
speed limiters are a simple, easy to implement, and inexpensive technology, we want to leave the
use of vehicle speed limiters to the truck purchaser. Since truck fleets purchase tractors today
with owner-set vehicle speed limiters, we considered not allowing GEM to recognize
performance of VSLs due to potential issues regarding whether any reductions would accrue
from installing VSLs, since they can be turned off. We ultimately concluded, as we did in Phase
1, that we should allow the use of VSLs that cannot be overridden by the operator as a means of
compliance for vehicle manufacturers that wish to offer it and truck purchasers that wish to
purchase the technology. In doing so, we are providing another means of meeting that standard
that can lower compliance cost and provide a more optimal vehicle solution for some truck
fleets. For example, a local beverage distributor may operate trucks in a distribution network of
primarily local roads. Under those conditions, aerodynamic fairings used to reduce aerodynamic
drag provide little benefit due to the low vehicle speed while adding additional mass to the
vehicle. A vehicle manufacturer could choose to install a VSL set at 55 mph for this customer.
The resulting tractor would be optimized for its intended application and would be fully
compliant with our program all at a lower cost to the ultimate tractor purchaser.H
However, as in Phase 1, we have chosen not to base the standards on performance of
VSLs because of concerns about how to set a realistic adoption rate that avoids unintended
adverse impacts. Although we expect there will be some use of VSL, currently it is used when
the fleet involved decides it is feasible and practicable and increases the overall efficiency of the
freight system for that fleet operator. To date, the compliance data provided by manufacturers
indicate that none of the tractor configurations include a tamper-proof VSL setting less than 65
mph. At this point the agencies are not in a position to determine in how many additional
situations use of a VSL would result in similar benefits to overall efficiency or how many
customers would be willing to accept a tamper-proof VSL setting. We are not able at this time to
quantify the potential loss in utility due to the use of VSLs. Absent this information, we cannot
make a determination regarding the reasonableness of setting a standard based on a particular
H The agencies note that because a VSL value can be input into GEM, its benefits can be directly assessed with the
model and off cycle credit applications therefore are not necessary even though the standard is not based on
performance of VSLs (i.e. VSL is an on-cycle technology).

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
VSL level. Therefore, the agencies are not premising the standards on use of VSL, and instead
would continue to rely on the industry to select VSL when circumstances are appropriate for its
use. The agencies have not included either the cost or benefit due to VSLs in analysis of the
program's costs and benefits.
2.8.3.11 Adoption Rates Used to Set the Heavy-Haul Tractor Standards
The agencies recognize that certain technologies used to determine the stringency of the
Phase 2 tractor standards are less applicable to heavy-haul tractors. Heavy-haul tractors are not
typically used in the same manner as long-haul tractors with extended highway driving, and
therefore will experience less benefit from aerodynamics. Aerodynamic technologies are very
effective at reducing the fuel consumption and GHG emissions of tractors, but only when
traveling at highway speeds. At lower speeds, the aerodynamic technologies may have a
detrimental impact due to the potential of added weight. The agencies therefore proposed not
considering the use of aerodynamic technologies in the development of the Phase 2 heavy-haul
tractor standards. Moreover, because aerodynamics will not play a role in the heavy-haul
standards, the agencies proposed to combine all of the heavy-haul tractor cab configurations (day
and sleeper) and roof heights (low, mid, and high) into a single heavy-haul tractor subcategory.
The agencies received comments regarding the applicability of aerodynamic technologies
on heavy-haul vehicles. After considering these comments, the agencies are using a technology
package that does not use aerodynamic improvements in setting the Phase 2 heavy-haul tractor
standards, as we proposed. 1
Certain powertrain and drivetrain components are also impacted during the design of a
heavy-haul tractor, including the transmission, axles, and the engine. Heavy-haul tractors
typically require transmissions with 13 or 18 speeds to provide the ratio spread to ensure that the
tractor is able to start pulling the load from a stop. Downspeed powertrains are typically not an
option for heavy-haul operations because these vehicles require more torque to move the vehicle
because of the heavier load. Finally, due to the loading requirements of the vehicle, it is not
likely that a 6x2 axle configuration can be used in heavy-haul applications.
We received comments from stakeholders about the application of technologies other
than aerodynamics for heavy-haul tractors. After considering these comments and the
information regarding the tire rolling resistance improvement opportunities, discussed in Section
III.D.l.b.iii, the agencies have adjusted the adoption rate of low rolling resistance tires.
Consistent with the changes made in the final rule for the adoption of low rolling resistance tires
in low and mid roof tractors, the agencies did not project any adoption of Level 3 tires for heavy-
haul tractors in the final rule.
2.8.3.12 Summary of the Adoption Rates used to determine the Standards
Table 2-34,
1 Since aerodynamic improvements are not part of the technology package, the agencies likewise are not adopting
any aero bin structure for the heavy-haul tractor subcategory.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-35, and Table 2-36 provide the adoption rates of each technology broken down
by weight class, cab configuration, and roof height.
Table 2-34 Technology Adoption Rates for Class 7 and 8 Tractors for Determining the 2021 MY Standards

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low
Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High Roof
Engine

2021MY
11L
Engine
350 HP
2021MY
11L
Engine
350 HP
2021MY
11L
Engine
350 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine
455 HP
2021MY
15L
Engine 455
HP
Aerodynamics
Bin I
10%
10%
0%
10%
10%
0%
0%
10%
0%
Bin II
10%
10%
0%
10%
10%
0%
20%
10%
0%
Bin III
70%
70%
60%
70%
70%
60%
60%
70%
60%
Bin IV
10%
10%
35%
10%
10%
35%
20%
10%
30%
Bin V
0%
0%
5%
0%
0%
5%
0%
0%
10%
Bin VI
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin VII
0%
0%
0%
0%
0%
0%
0%
0%
0%
Steer Tires
Base
5%
5%
5%
5%
5%
5%
5%
5%
5%
Level 1
35%
35%
35%
35%
35%
35%
35%
35%
35%
Level 2
50%
50%
50%
50%
50%
50%
50%
50%
50%
Level 3
10%
10%
10%
10%
10%
10%
10%
10%
10%
Drive Tires
Base
15%
15%
5%
15%
15%
5%
15%
15%
5%
Level 1
35%
35%
35%
35%
35%
35%
35%
35%
35%
Level 2
50%
50%
50%
50%
50%
50%
50%
50%
50%
Level 3
0%
0%
10%
0%
0%
10%
0%
0%
10%
Idle Reduction
Tamper Proof
AESS
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper Proof
AESS with
Diesel APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper Proof
AESS with
Battery APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper Proof
AESS with
Automatic
Stop-Start
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper Proof
AESS with
FOH
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
40%
40%
40%
AESS









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
30%
30%
30%
AESS with









Diesel APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









Battery APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









Automatic









Stop-Start









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









FOH









Transmission
Manual
0%
0%
0%
0%
0%
0%
0%
0%
0%
AMT
40%
40%
40%
40%
40%
40%
40%
40%
40%
Auto
10%
10%
10%
10%
10%
10%
10%
10%
10%
Dual Clutch
5%
5%
5%
5%
5%
5%
5%
5%
5%
Top Gear
20%
20%
20%
20%
20%
20%
20%
20%
20%
Direct Drive









Transmission
20%
20%
20%
20%
20%
20%
20%
20%
20%
Efficiency
Improvement









Neutral Idle
10%
10%
10%
10%
10%
10%
10%
10%
10%
Driveline
Axle
30%
30%
30%
30%
30%
30%
30%
30%
30%
Efficiency
Improvement









6x2, 6x4 Axle
N/A
N/A
N/A
15%
15%
15%
15%
15%
15%
Disconnect or









4x2 Axle









Downspeed
3.36
3.36
3.36
3.36
3.36
3.36
3.31
3.31
3.31
(Rear Axle









Ratio)









Accessory Improvements
A/C
10%
10%
10%
10%
10%
10%
10%
10%
10%
Efficiency









Electric
10%
10%
10%
10%
10%
10%
10%
10%
10%
Access.









Other Technologies
Predictive
20%
20%
20%
20%
20%
20%
20%
20%
20%
Cruise









Control









Automated
20%
20%
20%
20%
20%
20%
20%
20%
20%
Tire Inflation









System









Tire Pressure
20%
20%
20%
20%
20%
20%
20%
20%
20%
Monitoring
System









Neutral Coast
0%
0%
0%
0%
0%
0%
0%
0%
0%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-35 Technology Adoption Rates for Class 7 and 8 Tractors for Determining the 2024 MY Standards

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High Roof
Engine

2024MY
11L
Engine
350 HP
2024MY
11L
Engine
350 HP
2024MY
11L
Engine
350 HP
2024MY
15L
Engine
455 HP
2024MY
15L
Engine
455 HP
2024MY
15L
Engine
455 HP
2024MY
15L
Engine
455 HP
2024MY
15L
Engine
455 HP
2024MY
15L
Engine
455 HP
Aerodynamics
Bin I
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin II
20%
20%
0%
20%
20%
0%
20%
20%
0%
Bin III
60%
60%
40%
60%
60%
40%
60%
60%
40%
Bin IV
20%
20%
40%
20%
20%
40%
20%
20%
40%
Bin V
0%
0%
20%
0%
0%
20%
0%
0%
20%
Bin VI
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin VII
0%
0%
0%
0%
0%
0%
0%
0%
0%
Steer Tires
Base
5%
5%
5%
5%
5%
5%
5%
5%
5%
Level 1
25%
25%
15%
25%
25%
15%
25%
25%
15%
Level 2
55%
55%
60%
55%
55%
60%
55%
55%
60%
Level 3
15%
15%
20%
15%
15%
20%
15%
15%
20%
Drive Tires
Base
10%
10%
5%
10%
10%
5%
10%
10%
5%
Level 1
25%
25%
15%
25%
25%
15%
25%
25%
15%
Level 2
65%
65%
60%
65%
65%
60%
65%
65%
60%
Level 3
0%
0%
20%
0%
0%
20%
0%
0%
20%
Idle Reduction
Tamper
Proof AESS
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with Diesel
APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with Battery
APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with
Automatic
Stop-Start
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
withFOH
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Adjustable
AESS
N/A
N/A
N/A
N/A
N/A
N/A
30%
30%
30%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
40%
40%
40%
AESS with









Diesel APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









Battery APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









Automatic









Stop-Start









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
10%
10%
10%
AESS with









FOH









Transmission
Manual
0%
0%
0%
0%
0%
0%
0%
0%
0%
AMT
50%
50%
50%
50%
50%
50%
50%
50%
50%
Auto
20%
20%
20%
20%
20%
20%
20%
20%
20%
Dual Clutch
10%
10%
10%
10%
10%
10%
10%
10%
10%
Top Gear
50%
50%
50%
50%
50%
50%
50%
50%
50%
Direct Drive









Transmission
40%
40%
40%
40%
40%
40%
40%
40%
40%
Efficiency









Improvement









Neutral Idle
20%
20%
20%
20%
20%
20%
20%
20%
20%
Driveline
Axle
65%
65%
65%
65%
65%
65%
65%
65%
65%
Efficiency









Improvement









6x2, 6x4
N/A
N/A
N/A
25%
25%
25%
25%
25%
25%
Axle









Disconnect









or 4x2 Axle









Downspeed
3.31
3.31
3.31
3.31
3.31
3.31
3.26
3.26
3.26
(Rear Axle









Ratio)









Accessory Improvements
A/C
20%
20%
20%
20%
20%
20%
20%
20%
20%
Efficiency









Electric
20%
20%
20%
20%
20%
20%
20%
20%
20%
Access.









Other Technologies
Predictive
40%
40%
40%
40%
40%
40%
40%
40%
40%
Cruise









Control









Automated
25%
25%
25%
25%
25%
25%
25%
25%
25%
Tire Inflation









System









Tire Pressure
50%
50%
50%
50%
50%
50%
50%
50%
50%
Monitoring
System









Neutral
0%
0%
0%
0%
0%
0%
0%
0%
0%
Coast










-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-36 Technology Adoption Rates for Class 7 and 8 Tractors for Determining the 2027 MY Standards

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High
Roof
Low Roof
Mid Roof
High Roof
Engine

2027MY
11L
Engine
350 HP
2027MY
11L
Engine
350 HP
2027MY
11L
Engine
350 HP
2027MY
15L
Engine
455 HP
2027MY
15L
Engine
455 HP
2027MY
15L
Engine
455 HP
2027MY
15L
Engine
455 HP
2027MY
15L
Engine
455 HP
2027MY
15L
Engine
455 HP
Aerodynamics
Bin I
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin II
20%
20%
0%
20%
20%
0%
20%
20%
0%
Bin III
50%
50%
30%
50%
60%
30%
40%
50%
20%
Bin IV
30%
30%
30%
30%
20%
30%
40%
30%
30%
Bin V
0%
0%
40%
0%
0%
40%
0%
0%
50%
Bin VI
0%
0%
0%
0%
0%
0%
0%
0%
0%
Bin VII
0%
0%
0%
0%
0%
0%
0%
0%
0%
Steer Tires
Base
5%
5%
5%
5%
5%
5%
5%
5%
5%
Level 1
20%
20%
10%
20%
20%
10%
20%
20%
10%
Level 2
50%
50%
50%
50%
50%
50%
50%
50%
50%
Level 3
25%
25%
35%
25%
25%
35%
25%
25%
35%
Drive Tires
Base
5%
5%
5%
5%
5%
5%
5%
5%
5%
Level 1
10%
10%
10%
10%
10%
10%
10%
10%
10%
Level 2
85%
85%
50%
85%
85%
50%
85%
85%
50%
Level 3
0%
0%
35%
0%
0%
35%
0%
0%
35%
Idle Reduction
Tamper
Proof AESS
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with Diesel
APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with Battery
APU
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
with
Automatic
Stop-Start
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Tamper
Proof AESS
withFOH
N/A
N/A
N/A
N/A
N/A
N/A
0%
0%
0%
Adjustable
AESS
N/A
N/A
N/A
N/A
N/A
N/A
15%
15%
15%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
40%
40%
40%
AESS with









Diesel APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
15%
15%
15%
AESS with









Battery APU









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
15%
15%
15%
AESS with









Automatic









Stop-Start









Adjustable
N/A
N/A
N/A
N/A
N/A
N/A
15%
15%
15%
AESS with









FOH









Transmission
Manual
0%
0%
0%
0%
0%
0%
0%
0%
0%
AMT
50%
50%
50%
50%
50%
50%
50%
50%
50%
Auto
30%
30%
30%
30%
30%
30%
30%
30%
30%
Dual Clutch
10%
10%
10%
10%
10%
10%
10%
10%
10%
Top Gear
50%
50%
50%
50%
50%
50%
50%
50%
50%
Direct Drive









Transmission
70%
70%
70%
70%
70%
70%
70%
70%
70%
Efficiency









Improvement









Neutral Idle
30%
30%
30%
30%
30%
30%
30%
30%
30%
Driveline
Axle
80%
80%
80%
80%
80%
80%
80%
80%
80%
Efficiency









Improvement









6x2, 6x4
N/A
N/A
N/A
30%
30%
30%
30%
30%
30%
Axle









Disconnect









or 4x2 Axle









Downspeed
3.21
3.21
3.21
3.21
3.21
3.21
3.16
3.16
3.16
(Rear Axle









Ratio)









Accessory Improvements
A/C
30%
30%
30%
30%
30%
30%
30%
30%
30%
Efficiency









Electric
30%
30%
30%
30%
30%
30%
30%
30%
30%
Access.









Other Technologies
Predictive
40%
40%
40%
40%
40%
40%
40%
40%
40%
Cruise









Control









Automated
30%
30%
30%
30%
30%
30%
30%
30%
30%
Tire Inflation









System









Tire Pressure
70%
70%
70%
70%
70%
70%
70%
70%
70%
Monitoring
System









Neutral
0%
0%
0%
0%
0%
0%
0%
0%
0%
Coast










-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-37 includes the adoption rates of each technology used in setting the heavy-haul
tractor standards for 2021, 2024, and 2027 MY.
Table 2-37 Technology Adoption Rates for Heavy-Haul Tractors for Determining the 2021,2024, and 2027
MY Standards
HEAVY-HAUL TRACTOR APPLICATION RATES

2021MY
2024MY
2027MY
Engine
2021 MY 15L Engine with
600 HP with 2% reduction
over 2018 MY
2024 MY 15L Engine with
600 HP with 4.2%
reduction over 2018 MY
2027 MY 15L Engine with
600 HP with 5.4% reduction
over 2018 MY
Aerodynamics - 0%
Steer Tires
Phase 1 Baseline
15%
10%
5%
Level I
35%
30%
10%
Level 2
50%
60%
85%
Level 3
0%
0%
0%
Drive Tires
Phase 1 Baseline
15%
10%
5%
Level I
35%
30%
10%
Level 2
50%
60%
85%
Level 3
0%
0%
0%
Transmission
AMT
40%
50%
50%
Automatic with Neutral
Idle
10%
20%
20%
DCT
5%
10%
10%
Other Technologies
6x2 Axle
0%
0%
0%
Transmission Efficiency
20%
40%
70%
Axle Efficiency
30%
65%
80%
Predictive Cruise
Control
20%
40%
40%
Accessory
Improvements
10%
20%
20%
Air Conditioner
Efficiency
Improvements
10%
20%
20%
Automatic Tire Inflation
Systems
20%
25%
30%
Tire Pressure
Monitoring System
20%
50%
70%
The agencies are also adopting in Phase 2 provisions that allow the manufacturers to meet
an optional heavy Class 8 tractor standard that reflects both aerodynamic improvements, along
with the powertrain requirements that go along with higher GCWR. Table 2-38 reflects the
adoption rates for each of the technologies for each of the subcategories in MY 2021. The
technology packages closely reflect those in the primary Class 8 tractor program. The
exceptions include less aggressive targets for low rolling resistance tires, no 6x2 axle adoption
rates, and no downspeeding due to the heavier loads of these vehicles.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-38 GEM Inputs for 2021 MY Heavy Class 8 Tractor Standards
OPTIONAL HEAVY CLASS 8 TRACTOR APPLICATION RATES - 2021 MY

Low/Mid Roof Day
Cab
High Roof Day Cab
Low/Mid Roof Sleeper
Cab
High Roof Sleeper Cab
Engine
2021 MY 15L Engine
with 600 HP with 2%
reduction over 2018
MY
2021 MY 15L Engine
with 600 HP with 2%
reduction over 2018
MY
2021 MY 15L Engine
with 600 HP with 2%
reduction over 2018
MY
2021 MY 15L Engine
with 600 HP with 2%
reduction over 2018 MY
Aerodynamics
Bin I
10%
0%
10%
0%
Bin II
10%
0%
10%
0%
Bin III
70%
60%
70%
60%
Bin IV
10%
35%
10%
30%
Bin V
0%
5%
0%
10%
Bin VI
0%
0%
0%
0%
Bin VII
0%
0%
0%
0%
Steer Tires
Phase 1 Baseline
10%
5%
10%
5%
Level I
25%
35%
25%
35%
Level 2
65%
60%
65%
60%
Level 3
0%
0%
0%
0%
Drive Tires
Phase 1 Baseline
20%
10%
20%
10%
Level I
40%
30%
40%
30%
Level 2
40%
60%
40%
60%
Level 3
0%
0%
0%
0%
Transmission
AMT
40%
40%
40%
40%
Automatic with Neutral
Idle
10%
10%
10%
10%
DCT
5%
5%
5%
5%
Other Technologies
Adjustable AESS w/
Diesel APU
N/A
N/A
30%
30%
Adjustable AESS w/
Battery APU
N/A
N/A
10%
10%
Adjustable AESS w/
Automatic Stop-Start
N/A
N/A
10%
10%
Adjustable AESS w/
FOH Cold, Main Engine
Warm
N/A
N/A
10%
10%
Adjustable AESS
programmed to 5
minutes
N/A
N/A
40%
40%
Transmission Efficiency
20%
20%
20%
20%
Axle Efficiency
30%
30%
30%
30%
Predictive Cruise
Control
20%
20%
20%
20%
Accessory
Improvements
10%
10%
10%
10%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Air Conditioner
Efficiency
Improvements
10%
10%
10%
10%
Automatic Tire Inflation
Systems
20%
20%
20%
20%
Tire Pressure
Monitoring System
20%
20%
20%
20%
2.8.4 Derivation of the Tractor Standards
The agencies used the technology effectiveness inputs and technology adoption rates to
develop GEM inputs to derive the HD Phase 2 fuel consumption and CO2 emissions standards
for each subcategory of Class 7 and 8 combination tractors. Note that we have analyzed one
technology pathway for each level of stringency, but tractor manufacturers are free to use any
combination of technology to meet the standards on average.
2.8.4.1 2021 through 2027 MY Engine Fuel Maps
One of the most significant changes in the HD Phase 2 version of GEM is the allowance
for manufacturers to enter their own engine fuel maps by following the test procedure described
in the Chapter 3 Test Procedure section of this RIA. The GEM engine fuel map input file
consists of information in csv format. It contains a steady-state engine fueling map that includes
three columns: engine speed in rpm, engine torque in Nm, and engine fueling rate in g/s. New
for the final Phase 2 rule, the input file also includes a cycle average fuel map represented by
engine cycle work, the cycle-average engine speed to vehicle speed ratio, and the fuel mass in
grams. The input file also contains the engine full torque or lug curve in two columns: engine
speed in rpm and torque in NM. The input file also contains the motoring torque and uses the
same format and units as the full load torque curve. The idle fuel map is also included.
The agencies developed default engine fuel maps for all tractor subcategories, utilizing
the same format that the manufacturers would be required to provide. Fuel maps were developed
for the 2021, 2024, and 2027 model years by applying the technologies assumed in deriving the
engine standards and the additional technology effectiveness of new engine platforms (for 2027)
to the 2018 baseline engine fuel maps. Those default maps are derived from multiple sources of
confidential business information from different stakeholders together with engineering
judgment. A list of all of the engine fuel maps used in setting the standards for each subcategory
is given in Table 2-39. The model years covered by the maps are 2021, 2024, and 2027 are
shown from Figure 2-30 to Figure 2-38. In lieu of using 2021, 2024, and 2027 MY fuel maps for
the 15L 600 HP engine used in heavy-haul tractor standards and optional 2021 MY Heavy Class
8 tractor standards, we used the 2018 MY fuel map shown in Figure 2-19. We then applied a 2
percent reduction in 2021 MY, a 4.2 percent reduction in 2024 MY, and a 5.4 percent reduction
in 2027 MY in the GEM runs to determine the stringency of the standards.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-39 GEM Default CI Engine Fuel Maps for Tractors
REGULATORY SUBCATEGORY
ENGINE FUEL MAP
Class 8 Combination
Sleeper Cab - High Roof
15L-455 HP
Class 8 Combination
Sleeper Cab - Mid Roof
15L-455 HP
Class 8 Combination
Sleeper Cab - Low Roof
15L-455 HP
Class 8 Combination
Day Cab - High Roof
15L-455 HP
Class 8 Combination
Day Cab - Mid Roof
15L-455 HP
Class 8 Combination
Day Cab - Low Roof
15L-455 HP
Class 7 Combination
Day Cab - High Roof
11L - 350 HP
Class 7 Combination
Day Cab - Mid Roof
11L - 350 HP
Class 7 Combination
Day Cab - Low Roof
11L - 350 HP
Heavy Haul
Heavy-Haul and Heavy
Class 8 Tractors
15L - 600 HP
In vehicle applications, considering that market penetration of WHR would be different
between sleeper cab (SC) and day cab (DC) engines due to the nature of their different driving
cycles, the emission reductions should be different, and therefore, the engine fuel maps used in
GEM can be different as well. In addition, at least one new engine platform would be taken into
consideration, which means that more aggressive technology effectiveness is included in the
tractor vehicles in addition to higher market penetration of WHR. See Chapter 2.7.5 above.
As discussed in Section III.D(l)(b)(i) of the FRM Preamble, the agencies project that at
least one engine manufacturer (and possibly more) will have completed a redesign for tractor
engines by 2027. Accordingly, we project that 50 percent of tractor engines in 2027 will be
redesigned engines and be 1.6 percent more efficient than required by the engine standards, so
the average engine would be 0.8 percent better.145 However, we could have projected the same
overall improvement by projecting 25 percent of engine get 3.2 percent better. Based on the CBI
information available to us, we believe projecting a 0.8 percent improvement is somewhat
conservative.
Adding this 0.8 percent improvement to the 5.1 reduction required by the standards
means we project the average 2027 tractor engine would be 5.9 percent better than Phase 1.
Because engine improvements for tractors are applied separately for day cabs and sleeper cabs in
the vehicle program, we estimated separate improvements for them here. Specifically, we
project a 5.4 percent reduction for day cabs and a 6.4 percent reduction in fuel consumption in
sleeper cabs beyond Phase 1. It is important to also note that manufacturers that do not achieve
this level would be able to make up for the difference by applying one of the many other tractor
technologies to a greater extent than we project, or to achieve greater reductions by optimizing
technology efficiency further. We are not including the cost of developing these new engines in
our cost analysis because we believe these engines are going to be developed due to market
forces (i.e., the new platform, already contemplated) rather than due to this rulemaking.
The default fuel maps are created for use in GEM. As just explained, use of different
WHR market penetration rates between sleeper cabs and day cabs results in unique fuel maps for
each.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Figure 2-30 to Figure 2-38 show all the engine fuel maps used in GEM for years 2021 to
2027, for sleeper cab and day cab vehicles with 455hp rating engines and 350hp rating engines.
2021 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
1200
1000
800
600
400
200
0™
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-30 2021 Engine Fuel Map with 455hp Rating Used For Sleeper Cab
2021 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
00
1800
1600
1400
z 1200
S 1000
800
600
400
200
600
800 1 000 1200 1400 1600 1 800 2000 2200
Speed ( RPM )
Figure 2-31 2021 Engine Fuel Map with 455hp Rating Used For Day Cab

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review
2021 Engine 350hp / 11L BSFC ( g / kW * hr)
1600
CO
1400
1200
1000
800

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2024 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
E
z
1200
0)
= 1000
b
i—
800
600
200
210
225
400
225
200
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-34 2024 Engine Fuel Map with 455hp Rating Used For Day Cab
2024 Engine 350hp/11L BSFC ( g / kW * hr)
1600
1400
1200
1000
E
z
800
0)
3
0-
b
1—
600
400
--25!
200
600
800 1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-35 2024 Engine Fuel Map with 350hp Rating Used For Class 7 Tractor

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2027 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
Z 1200
.0=
1000
800
600
-\95
205
220
400
220
200
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM)
Figure 2-36 2027 Engine Fuel Map with 455hp Rating Used For Sleeper Cab
2027 Engine 455hp / 15L BSFC ( g / k\/V * hr)
2000
600
400
E
z
200
(D
g- 1000
b
H 800
600
195
205
-225
400
225
200
600
800
1000 1200 1400 1600
Speed ( RPM )
2000 2200
Figure 2-37 2027 Engine Fuel Map with 455hp Rating Used For Day Cab

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2027 Engine 350hp/ 11L BSFC ( g / kW * hr)
1600
1400
1200
1000
E
z
ง 800
w
o
i—
600
400
230
200
600 800 1000 1200 1400 1600 1 800 2000 2200
Speed ( RPM )
Figure 2-38 2027 Engine Fuel Map with 350hp Rating Used For Class 7 Tractor
2.8.4.2 GEM Inputs Used in Setting the Tractor Standards
As such, the agencies derived a standard for each subcategory by weighting the
individual GEM input parameters included in Table 2-30 with the adoption rates in Table 2-34,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-35, and Table 2-36. For example, the CdA value for a 2021MY Class 8 Sleeper
Cab High Roof scenario case was derived as 60 percent times 5.95 plus 30 percent times 5.40
plus 10 percent times 4.90, which is equal to a CdA of 5.68 m2 Similar calculations were made
for tire rolling resistance, transmission types, idle reduction, and other technologies. To account
for the engine standards and engine technologies, the agencies developed engine fuel maps for
GEM, as described in the section above.J The agencies then ran GEM with a single set of
vehicle inputs, as shown in Table 2-40, to derive the standards for each subcategory.
Table 2-40 GEM Inputs for the 2021MY Class 7 and 8 Tractor Standard Setting
CLASS 7
CLASS 8
Day Cab
Day Cab
Sleeper Cab
Low
Mid
High Roof
Low Roof
Mid
High Roof
Low Roof
Mid
High
Roof
Roof


Roof


Roof
Roof
Engine
2021MY
2021MY
2021MY
2021MY
2021MY
2021MY
2021MY
2021MY
2021MY
11L
11L
11L
15L
15L
15L
15L
15L
15L
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
350 HP
350 HP
350 HP
455 HP
455 HP
455 HP
455 HP
455 HP
455 HP
Aerodynamics (CdA in m2)
5.24
6.33
6.01
5.24
6.33
6.01
5.24
6.33
5.68
Steer Tires (CRR in kg/metric ton)
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
Drive Tires (CRR in kg/metric ton)
6.6
6.6
6.3
6.6
6.6
6.3
6.6
6.6
6.3
Extended Idle Reduction Weighted Effectiveness
N/A
N/A
N/A
N/A
N/A
N/A
2.3%
2.3%
2.3%


Transmission = 10 speed Manual Transmission



Gear Ratios = 12.8, 9.25, 6.76, 4.90, 3.58, 2.61, 1.89, 1.38, 1.00, 0.73

Drive Axle Ratio = 3.36 for day cabs, 3.31 for sleeper cabs
6x2 Axle Weighted Effectiveness
N/A
N/A
N/A
0.3%
0.3%
0.3%
0.3%
0.3%
0.3%


Transmission Type Weighted Effectiveness =
1.1%


Neutral Idle Weighted Effectiveness
0.1%
0.1%
0.1%
0.1%
0.1%
0.1%
0.02%
0.02%
0.02%
Direct Drive Weighted Effectiveness = 0.4%
Transmission Efficiency Weighted Effectiveness = 0.2%
Axle Efficiency Improvement = 0.6%


Air Conditioner Efficiency Improvements =
0.1%


Accessory Improvements = 0.1%
Predictive Cruise Control =0.4%
Automatic Tire Inflation Systems = 0.3%
Tire Pressure Monitoring System = 0.2%
Phase 1 Credit Carry-over = 1%
1 See RIA Chapter 2.7 explaining the derivation of the engine standards.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-41 GEM Inputs for the 2024MY Class 7 and 8 Tractor Standard Setting
CLASS 7
CLASS 8
Day Cab
Day Cab
Sleeper Cab
Low
Mid
High Roof
Low Roof
Mid
High Roof
Low Roof
Mid
High
Roof
Roof


Roof


Roof
Roof
Engine
2024MY
2024MY
2024MY
2024MY
2024MY
2024MY
2024MY
2024MY
2024MY
11L
11L
11L
15L
15L
15L
15L
15L
15L
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
350 HP
350 HP
350 HP
455 HP
455 HP
455 HP
455 HP
455 HP
455 HP
Aerodynamics (CdA in m2)
5.16
6.25
5.82
5.16
6.25
5.82
5.16
6.25
5.52
Steer Tires (CRR in kg/metric ton)
5.9
5.9
5.8
5.9
5.9
5.8
5.9
5.9
5.8
Drive Tires (CRR in kg/metric ton)
6.4
6.4
6.0
6.4
6.4
6.0
6.4
6.4
6.0
Extended Idle Reduction Weighted Effectiveness
N/A
N/A
N/A
N/A
N/A
N/A
2.5%
2.5%
2.5%


Transmission = 10 speed Manual Transmission



Gear Ratios = 12.8, 9.25, 6.76, 4.90, 3.58, 2.61, 1.89, 1.38, 1.00, 0.73

Drive Axle Ratio = 3.31 for day cabs, 3.26 for sleeper cabs
6x2 Axle Weighted Effectiveness
N/A
N/A
N/A
0.5%
0.5%
0.5%
0.5%
0.5%
0.5%


Transmission Type Weighted Effectiveness =
1.6%


Neutral Idle Weighted Effectiveness
0.2%
0.2%
0.2%
0.2%
0.2%
0.2%
0.03%
0.03%
0.03%
Direct Drive Weighted Effectiveness = 1.0%
Transmission Efficiency Weighted Effectiveness = 0.4%
Axle Efficiency Improvement =1.3%


Air Conditioner Efficiency Improvements =
0.1%


Accessory Improvements = 0.2%
Predictive Cruise Control =0.8%
Automatic Tire Inflation Systems = 0.3%
Tire Pressure Monitoring System = 0.5%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-42 GEM Inputs for the 2027MY Class 7 and 8 Tractor Standard Setting
CLASS 7
CLASS 8
Day Cab
Day Cab
Sleeper Cab
Low
Mid
High Roof
Low Roof
Mid
High Roof
Low Roof
Mid
High
Roof
Roof


Roof


Roof
Roof
Engine
2027MY
2027MY
2027MY
2027MY
2027MY
2027MY
2027MY
2027MY
2027MY
11L
11L
11L
15L
15L
15L
15L
15L
15L
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
Engine
350 HP
350 HP
350 HP
455 HP
455 HP
455 HP
455 HP
455 HP
455 HP
Aerodynamics (CdA in m2)
5.12
6.21
5.67
5.12
6.21
5.67
5.08
6.21
5.26
Steer Tires (CRR in kg/metric ton)
5.8
5.8
5.6
5.8
5.8
5.6
5.8
5.8
5.6
Drive Tires (CRR in kg/metric ton)
6.2
6.2
5.8
6.2
6.2
5.8
6.2
6.2
5.8
Extended Idle Reduction Weighted Effectiveness
N/A
N/A
N/A
N/A
N/A
N/A
3%
3%
3%


Transmission = 10 speed Manual Transmission



Gear Ratios = 12.8, 9.25, 6.76, 4.90, 3.58, 2.61, 1.89, 1.38, 1.00, 0.73

Drive Axle Ratio = 3.21 for day cabs, 3.16 for sleeper cabs
6x2 Axle Weighted Effectiveness
N/A
N/A
N/A
0.6%
0.6%
0.6%
0.6%
0.6%
0.6%


Transmission Type Weighted Effectiveness =
1.6%


Neutral Idle Weighted Effectiveness
0.2%
0.2%
0.2%
0.2%
0.2%
0.2%
0.03%
0.03%
0.03%
Direct Drive Weighted Effectiveness = 1.0%
Transmission Efficiency Weighted Effectiveness = 0.7%
Axle Efficiency Improvement = 1.6%


Air Conditioner Efficiency Improvements =
0.3%


Accessory Improvements = 0.2%
Predictive Cruise Control =0.8%
Automatic Tire Inflation Systems = 0.4%
Tire Pressure Monitoring System = 0.7%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-43 GEM Inputs for the 2021,2024, and 2027MY Heavy-Haul Tractor Standard Setting
2021MY
2024MY
2027MY
Engine = 2021 MY 15L
Engine with 600 HP
Engine = 2024 MY 15L
Engine with 600 HP
Engine = 2027 MY 15L
Engine with 600 HP
Aerodynamics (CdA in m2) = 5.00
Steer Tires (CRR in
kg/metric ton) = 6.2
Steer Tires (CRR in
kg/metric ton) = 6.0
Steer Tires (CRR in
kg/metric ton) = 5.8
Drive Tires (CRR in
kg/metric ton) = 6.6
Drive Tires (CRR in
kg/metric ton) = 6.4
Drive Tires (CRR in
kg/metric ton) = 6.2
Transmission = 18 speed
Manual Transmission
Transmission = 18 speed
Manual Transmission
Transmission = 18 speed
Manual Transmission
Drive axle Ratio = 3.70
Drive axle Ratio = 3.70
Drive axle Ratio = 3.70
6x2 Axle Weighted
Effectiveness = 0%
6x2 Axle Weighted
Effectiveness = 0%
6x2 Axle Weighted
Effectiveness = 0%
Transmission benefit = 1.1%
Transmission benefit =
1.8%
Transmission benefit = 1.8%
Transmission
Efficiency=0.2%
Transmission
Efficiency=0.4%
Transmission
Efficiency=0.7%
Axle Efficiency=0.3%
Axle Efficiency=0.7%
Axle Efficiency=1.6%
Predictive Cruise
Control=0.4%
Predictive Cruise Control
=0.8%
Predictive Cruise Control
=0.8%
Accessory Improvements =
0.1%
Accessory Improvements =
0.2%
Accessory Improvements =
0.3%
Air Conditioner Efficiency
Improvements= 0.1%
Air Conditioner Efficiency
Improvements = 0.1%
Air Conditioner Efficiency
Improvements = 0.2%
Automatic Tire Inflation
Systems = 0.3%
Automatic Tire Inflation
Systems = 0.3%
Automatic Tire Inflation
Systems = 0.4%
Tire Pressure Monitoring
System= 0.2%
Tire Pressure Monitoring
System= 0.5%
Tire Pressure Monitoring
System= 0.7%
The agencies ran GEM with a single set of vehicle inputs, as shown in Table 2-44, to
derive the optional standards for each subcategory of the Heavy Class 8 tractors.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-44 GEM Inputs for 2021 MY Heavy Class 8 Tractor Standards
HEAVY CLASS 8 GEM INPUTS FOR 2021 MY
Day Cab
Sleeper Cab
Low Roof
Mid Roof
High Roof
Low Roof
Mid Roof
High Roof
2021MY 15L Engine 600 HP
Aerodynamics (CdA in m2)
5.2
6.3
6.0
5.2
6.3
5.7
Steer Tires (CRR in kg/metric ton)
6.1
6.1
6.1
6.1
6.1
6.1
Drive Tires (CRR in kg/metric ton)
6.S
6.S
6.5
6.S
6.S
6.5
Extended Idle Reduction Weighted Effectiveness
N/A
N/A
N/A
2.3%
2.3%
2.3%
Transmission = 18 speed Manual Transmission
Drive Axle Ratio = 3.73
Transmission Type Weighted Effectiveness = 1.1%
Neutral Idle Weighted Effectiveness
0.1%
0.1%
0.1%
0.1%
0.1%
0.1%
Direct Drive Weighted Effectiveness = 0.4%
Transmission Efficiency Weighted Effectiveness = 0.2%
Axle Efficiency Improvement = 0.6%
Air Conditioner Efficiency Improvements = 0.1%
Accessory Improvements = 0.1%
Predictive Cruise Control =0.4%
Automatic Tire Inflation Systems = 0.3%
Tire Pressure Monitoring System = 0.2%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The levels of the 2021, 2024, and 2027 model year standards for each subcategory are
included in Table 2-45.
Table 2-45 2021,2024, and 2027 Model Year Tractor Standards
2021 MODEL YEAR C02 GRAMS PER TON-MILE

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
105.5
80.5
72.3
52.4
Mid Roof
113.2
85.4
78.0
High Roof
113.5
85.6
75.7
2021 Model Year Gallons of Fuel per 1,000 Ton-Mile

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
10.36346
7.90766
7.10216
5.14735
Mid Roof
11.11984
8.38900
7.66208
High Roof
11.14931
8.40864
7.43615
2024 Model Year CO2 Grams per r
"on-Mile

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
99.8
76.2
68.0
50.2
Mid Roof
107.1
80.9
73.5
High Roof
106.6
80.4
70.7
2024 Model Year and Later Gallons of Fuel per 1,000 Ton-Mile

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
9.80354
7.48527
6.67976
4.93124
Mid Roof
10.52063
7.94695
7.22004
High Roof
10.47151
7.89784
6.94499
2027 Model Year CO2 Grams per r
"on-Milea

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
96.2
73.4
64.1
48.3
Mid Roof
103.4
78.0
69.6
High Roof
100.0
75.7
64.3
2027 Model Year and Later Gallons of Fuel per 1,000 Ton-Mile

Day Cab
Sleeper Cab
Heavy-Haul

Class 7
Class 8
Class 8
Class 8
Low Roof
9.44990
7.21022
6.29666
4.74460
Mid Roof
10.15717
7.66208
6.83694
High Roof
9.82318
7.43615
6.31631
The 2027 MY standards for the high roof day cabs and high roof sleeper cab include the
0.3 m2 reduction in CdA built into GEM to reflect a change in the standard trailer (see Preamble
Section III.E.2.a.viii). This change lowers the numerical value of the standard, but does not
impact the stringency (i.e., the effectiveness of the technology packages that need to be installed
on a tractor to be compliant with the standards). Therefore, the percent reductions reported

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
throughout the Preamble to the final rule reflect only the effectiveness of the technology package
needed to meet the standard and does not include the change in CdA built into GEM. See Table
2-46 for the percent reduction calculations for high roof tractors in MY 2027.
Table 2-46 Percent Reductions for 2027MY High Roof Tractors

CLASS 7
HIGH ROOF
TRACTOR
CLASS 8 HIGH
ROOF DAY
CAB
CLASS 8 HIGH
ROOF SLEEPER
CAB
Baseline GEM Output
2018 MY (g/ton-mile)
129.7
98.2
87.8
2027 MY GEM Output
with 0.3 m2 CdA (g/ton-
mile)
100.0
75.7
64.3
2027 MY GEM Output
without 0.3 m2 CdA
(g/ton-mile)
102.0
77.0
65.7
% Reduction in Stringency
due to Technology
Package Only
21%
22%
25%
The level of the Phase 2 2021 model year optional Heavy Class 8 standards for each
subcategory is included in Table 2-47.
Table 2-47 Phase 2 Optional Heavy Class 8 Standards
OPTIO]
\AL HEAVY CLASS 8 TRACTOR STANDARDS
Low Roof Day
Cab
Mid Roof
Day Cab
High Roof
Day Cab
Low Roof
Sleeper Cab
Mid Roof
Sleeper Cab
High Roof
Sleeper Cab
2021 Model Year CO2 Standards (Grams per Ton-Mile)
51.8
54.1
54.1
45.3
47.9
46.9
2021 MY and Later Fuel Consum
ption (gallons of Fuel per 1,000 Ton-Mile)
5.08841 5.31434 5.31434
4.44990 4.70530 4.60707
2.8.5 Tractor Package Costs of the Standards
A summary of the technology package costs under the final standard and relative to the
flat baseline is included in Table 2-48 through Table 2-51 for MYs 2021, 2024, and 2027,
respectively. RIA Chapter 2.11 includes the technology costs for the individual technologies.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-48 Class 7 and 8 Tractor Technology Incremental Costs in the 2021 Model Yeara b
Final Standards vs. the Flat Baseline (2013$ per vehicle)

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low/Mid
High
Low/ Mid
High
Low
Mid
High

Roof
Roof
Roof
Roof
Roof
Roof
Roof
Engine0
$284
$284
$284
$284
$284
$284
$284
Aerodynamics
$164
$299
$164
$299
$119
$119
$349
Tires
$39
$9
$61
$16
$61
$56
$16
Tire inflation







system
$259
$259
$300
$300
$300
$300
$300
Transmission
$4,096
$4,096
$4,096
$4,096
$4,096
$4,096
$4,096
Axle & axle







lubes
$71
$71
$101
$101
$101
$101
$101
Idle reduction







with APU
$0
$0
$0
$0
$1,998
$1,998
$1,909
Air conditioning
$17
$17
$17
$17
$17
$17
$17
Other vehicle







technologies
$204
$204
$204
$204
$204
$204
$204
Total
$5,134
$5,240
$5,228
$5,317
$7,181
$7,175
$7,276
Notes:
a Costs shown are for the 2021 model year and are incremental to the costs of a baseline Phase 2 tractor. These costs include
indirect costs via markups along with learning impacts. For a description of the markups and learning impacts considered in this
analysis and how it impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated tractor classes. To see the actual estimated technology costs exclusive of
adoption rates, refer to Chapter 2.11 of this RIA.
c Engine costs are for a heavy HD diesel engine meant for a combination tractor (see Table 2-14).

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-49 Class 7 and 8 Tractor Technology Incremental Costs in the 2024 Model Yeara b
Final Standards vs. the Flat Baseline (2013$ per vehicle)

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low/Mid
High
Low/ Mid
High
Low
Mid
High

Roof
Roof
Roof
Roof
Roof
Roof
Roof
Engine0
$712
$712
$712
$712
$712
$712
$712
Aerodynamics
$264
$465
$264
$465
$217
$217
$467
Tires
$40
$12
$65
$20
$65
$65
$20
Tire inflation







system
$383
$383
$477
$477
$477
$477
$477
Transmission
$6,092
$6,092
$6,092
$6,092
$6,092
$6,092
$6,092
Axle & axle







lubes
$139
$139
$185
$185
$185
$185
$185
Idle reduction







with APU
$0
$0
$0
$0
$2,946
$2,946
$2,946
Air conditioning
$32
$32
$32
$32
$32
$32
$32
Other vehicle







technologies
$374
$374
$374
$374
$374
$374
$374
Total
$8,037
$8,210
$8,201
$8,358
$11,100
$11,100
$11,306
Notes:
a Costs shown are for the 2021 model year and are incremental to the costs of a baseline Phase 2 tractor. These costs include
indirect costs via markups along with learning impacts. For a description of the markups and learning impacts considered in this
analysis and how it impacts technology costs for other years, refer to Chapter 2.11 of this RIA.
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated tractor classes. To see the actual estimated technology costs exclusive of
adoption rates, refer to Chapter 2.11 of this RIA.
c Engine costs are for a heavy HD diesel engine meant for a combination tractor (see Table 2-18).

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-50 Class 7 and 8 Tractor Technology Incremental Costs in the 2027 Model Yeara b
Final Standards vs. the Flat Baseline (2013$ per vehicle)

CLASS 7
CLASS 8

Day Cab
Day Cab
Sleeper Cab

Low/Mid
High
Low/ Mid
High
Low
Mid
High

Roof
Roof
Roof
Roof
Roof
Roof
Roof
Engine0
$1,579
$1,579
$1,579
$1,579
$1,579
$1,579
$1,579
Aerodynamics
$453
$547
$453
$547
$415
$415
$639
Tires
$43
$12
$70
$20
$70
$70
$20
Tire inflation







system
$469
$469
$594
$594
$594
$594
$594
Transmission
$7,098
$7,098
$7,098
$7,098
$7,098
$7,098
$7,098
Axle & axle







lubes
$168
$168
$220
$220
$220
$220
$220
Idle reduction







with APU
$0
$0
$0
$0
$3,134
$3,173
$3,173
Air conditioning
$45
$45
$45
$45
$45
$45
$45
Other vehicle







technologies
$380
$380
$380
$380
$380
$380
$380
Total
$10,235
$10,298
$10,439
$10,483
$13,535
$13,574
$13,749
Notes:
a Costs shown are for the 2021 model year and are incremental to the costs of a baseline Phase 2 tractor. These costs include
indirect costs via markups along with learning impacts. For a description of the markups and learning impacts considered in this
analysis and how it impacts technology costs for other years, refer to Chapter 2.11 of this RIA.
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated tractor classes. To see the actual estimated technology costs exclusive of
adoption rates, refer to Chapter 2.11 of this RIA.
c Engine costs are for a heavy HD diesel engine meant for a combination tractor (see Table 2-22).
Table 2-51 Heavy-Haul Tractor Technology Incremental Costs in the 2021,2024, and 2027 Model Yeara b
Final Standards vs. the Less Dynamic Baseline (2013$ per vehicle)

2021 MY
2024 MY
2027 MY
Engine0
$284
$712
$1,579
Tires
$61
$65
$70
Tire inflation system
$300
$477
$594
Transmission
$4,096
$6,092
$7,098
Axle Efficiency
$101
$185
$220
Air conditioning
$17
$32
$45
Other vehicle technologies
$204
$374
$380
Total
$5,063
$7,937
$9,986
Notes:
a Costs shown are for the specified model year and are incremental to the costs of a baseline
Phase 2 tractor. These costs include indirect costs via markups along with learning impacts.
For a description of the markups and learning impacts considered in this analysis and how it
impacts technology costs for other years, refer to Chapter 2 of the RIA (see RIA 2.11).
b Note that values in this table include projected technology penetration rates. Therefore,
the technology costs shown reflect the average cost expected for each of the indicated
tractor classes. To see the actual estimated technology costs exclusive of adoption rates,
refer to Chapter 2 of the RIA (see RIA 2.11 in particular).
c Engine costs are for a heavy HD diesel engine meant for a combination tractor.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.9 Technology Application and Estimated Costs - Vocational Vehicles
This section describes the technical analysis supporting the derivation of the vocational
vehicle standards, including technology effectiveness and adoption rates. For purposes of setting
standards, the agencies have established a unique baseline vocational vehicle configuration for
each of the vocational vehicle regulatory subcategories, including nine diesel subcategories, nine
gasoline subcategories, and seven custom chassis subcategories. For purposes of demonstrating
compliance, some of the attributes and parameters are fixed by the agencies and are not available
as manufacturer inputs to GEM, while some are available to manufacturers when identifying
configurations to certify in the model years of the HD Phase 2 program.
2.9.1 Vocational Engines
This section describes the engines the agencies selected to incorporate into the baseline
vehicle configurations for the vocational vehicle subcategories, and how we used the GEM tool
to establish performance levels of these baseline vehicles. The agencies have developed models
for engines that represent performance of the technologies we expect would be installed in
vocational vehicles in the baseline year of 2017. A description of the technologies applied to our
2017 diesel engine models can be found above in Chapter 2.7 of this RIA, and gasoline engine
technologies are described in RIA Chapter 2.6. A description of the GEM engine simulation can
be found in RIA Chapter 4.
One of the most significant changes in the HD Phase 2 version of GEM is the provision
for manufacturers to enter their own engine fuel maps by following the test procedure described
in the RIA Chapter 3. The GEM engine fuel map input file consists of information in csv format.
It contains a steady-state engine fueling map that includes three columns: engine speed in rpm,
engine torque in Nm, and engine fueling rate in g/s. New for the final Phase 2 rules, the input
file also includes a cycle average fuel map represented by engine cycle work, the cycle-average
engine speed to vehicle speed ratio, and the fuel mass in grams. The input file also contains the
engine full torque or lug curve in two columns: engine speed in rpm and torque in NM. The
input file also contains the motoring torque and uses the same format and units as the full load
torque curve. The idle fuel map is also included.
2.9.1.1 Baseline Vocational Engines
The agencies have developed the vehicle standards using engine fuel maps described in
this section for all vocational vehicle sub-categories, utilizing the same format that the OEMs
will be required to provide when demonstrating compliance. Four sets of diesel engine maps
cover the nine primary diesel vocational vehicle regulatory subcategories and the seven custom
chassis subcategories, and one gasoline engine map covers the six gasoline vocational vehicle
regulatory subcategories, as summarized in Table 2-52. This means that some of the
subcategories share the same engine fuel map (and appropriately so; the agencies anticipate
common use of these engine platforms in real world application; see Chapter 2.7.5 above). For
example, all MHD diesel subcategories are powered by the same 7L engine with 270 hp rating,
as this is a very popular rating for engines in class 6-7 vocational vehicles in the U.S.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The agencies selected the 15L as the primary engine for the Regional HHD subcategory
because these vocational vehicles often require a similar level of power as a day cab tractor.
Also, the same engine hardware is often used for both tractor and vocational vehicles. It would
not be cost effective to develop two complete engines from one manufacturer in order to meet
two different market needs. The same principle is applied to 11L engines. We have made
changes to this 11L engine since proposal, from a 345hp to a 350hp rating for the HHD
subcategories. As proposed, the engine displacements and power ratings for the diesel MHD and
LHD vocational subcategories are the same as those simulated in GEM for Phase 1. More
details about the comments received on vocational engines and our responses with respect to
selection of baseline engines can be found in the Preamble at Section V.C and in the RTC
Section 6.
Table 2-52 GEM Engines for Vocational Vehicles
REGULATORY SUBCATEGORY AND DUTY CYCLE
ENGINE FUEL MAP
CI Heavy Heavy-Duty (Class 8)
Regional and Multipurpose Duty Cycles
15L - 455 HP
CI Heavy Heavy-Duty (Class 8)
Regional, Multi-Purpose, and Urban
Duty Cycles
11L- 350HP
CI Medium Heavy-Duty (Class 6-
7)
Regional, Multi-Purpose, and Urban
Duty Cycles
7L - 270 HP
CI Light Heavy-Duty (Class 2b-5)
Regional, Multi-Purpose, and Urban
Duty Cycles
7L - 200 HP
SI Heavy-Duty (Class 2b-8)
Regional, Multi-Purpose, and Urban
Duty Cycles
6.8L - 300 HP
Working with SwRI, the agencies have developed a baseline fuel map for an SI engine
intended for vocational vehicles. Based on testing at SwRI from a 2015 Ford 6.8L gasoline
engine, two key technologies are introduced to develop this baseline engine: cam phasing and
cooled EGR through a comprehensive engine modeling using GT-Power. It is recognized that it
would be very challenging to develop a map that can exactly match the proposed standards of
627 g/hp-hr numerically with the engine modeling approach taken. Consequently, the small
adjustment would have to be taken in order to match 627 g/hp-hr exactly. This can be done by
taking the ratio of whatever value obtained from modeling to 627g/hp-hr, and multiplying it to
the entire map if the final numerical values derived from GT-Power engine modeling is different
from the standards. More detailed process of this map development can be seen in Chapter 5.4
of the SwRI report146. It should be pointed out that this technology path is just one of many other
potential road maps that can achieve the standards. We believe this reasonably represents a
gasoline engine that complies with the applicable MY 2016 engine standard as shown in Figure
2-39.146

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Figure 2-39 Gasoline Engine Fuel Map for 300hp Rating
Vocational diesel baseline engine maps for MY 2018 are presented in Chapter 2.7 above.
Specifically, see Figure 2-17 to see the map of the 350 hp engine, Figure 2-18 for a map of the
455 hp engine, Figure 2-20 for a map of the 270 hp engine, and Figure 2-21 for a map of the 200
hp engine.
2.9.1.2 Improved Vocational Engines for Phase 2 Standard-Setting
The agencies developed four model year versions of these engine maps for each of these
four diesel engines: one set for MY 2017 as the baseline, a set of maps for MY2021, a set for
MY2024, and a set for MY 2027, as improved over the 2017 baseline engine maps.
2.9.1.2.1 Vocational Gasoline Engine Technology for Standard-Setting
Although the agencies will retain the Phase 1 SI separate engine standard for all
implementation years of Phase 2, we developed the Phase 2 standards for vocational vehicles
powered by SI engines, in part, to reflect performance of additional engine technology.K When
developing improvement levels for the stringency of the MY 2021, MY 2024, and MY 2027
vehicle standards, the agencies analyzed adoption rates, effectiveness, and cost of cylinder
deactivation and SI engine technologies that reduce friction. Consistent with our projection of
adoption rates of advanced engine friction reduction on HD gasoline pickup trucks, the agencies
projected that 44 percent of SI engines intended for vocational vehicles would already have
technologies applied that achieve performance equivalent to Level 2 engine friction reduction,
enabling a projected adoption rate of 56 percent of SI vocational engines that could upgrade to
Level 2. In terms of effectiveness, the agencies relied on the data presented in the Joint
Technical Support Document (TSD) published in support of the LD GHG final rulemaking.147
K The agencies did so in part in response to comments indicating that improvements in SI engine performance over
the baseline were feasible.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
In Chapter 3 of that document, the agencies present effectiveness values for upgrading from
baseline levels of engine friction reduction to Level 2 (EFR2) as ranging from 3.4 percent to 4.8
percent, for a range of LD vehicle types, and with large trucks falling in the middle of this range.
The TSD describes example technologies as including low-tension piston rings, piston skirt
design, roller cam followers, improved crankshaft design and bearings, material coatings,
material substitution, more optimal thermal management, and piston and cylinder surface
treatments. For this Phase 2 HD rulemaking, the agencies derived incremental EFR2
effectiveness values from the combined EFR1+EFR2 values that were relative to baseline-level
friction reduction. We were able to do this because the TSD also presented incremental
improvements for upgrading from EFR1 to EFR2 as ranging from 0.83 to 1.37. Using the same
reasoning as explained at proposal, the effectiveness and adoption rate of Level 2 engine friction
reduction is estimated to yield a fuel efficiency improvement of 0.6 percent.
Cylinder deactivation is considered as a technology in the HD pickup and van program,
and it can be an effective technology for vocational vehicles with high power to vehicle weight
ratios in driving conditions that don't demand full load operation. Table VI-6 in Preamble
Section VI shows that expected improvements in fuel consumption due to application of cylinder
deactivation on HD pickups and vans are on the order of two to three percent over the applicable
chassis dynamometer test cycle. The discussion in Section VI.E. 8 of the Preamble explains the
reasoning behind the agencies' decision to predicate the HD SI pickup standards on 56 percent
adoption of cylinder deactivation. Because of differences in offerings between engines sold in
complete pickup trucks and those sold in vocational vehicles, we are applying only 30 percent
adoption of cylinder deactivation for SI vocational vehicle-level improvements. Because of
differences in driving patterns and test procedures between HD pickup trucks and vocational
vehicles, we are not applying the same effectiveness as for the pickups, instead we are applying a
cycle average effectiveness of one percent. Further, because friction reduction and cylinder
deactivation act in some overlapping ways to improve efficiency of engines, we are applying a
dis-synergy factor of 0.9. Thus the combination of these technologies results in a calculated
package effectiveness value of 0.8 percent, which we apply in each model year of Phase 2
standards. In terms of costs, the agencies have presented the costs of upgrading from EFR1 to
EFR2, as shown in Chapter 2.11.2.17 below. The costs of cylinder deactivation are shown in
Chapter 2.11.2.18. By applying our market adoption rates and incremental costs of these two
technologies, we estimate a vocational vehicle package cost due to improved SI engines of $138
in MY 2021 for this technology.
2.9.1.2.2 Improved Vocational Diesel Engine Technology for Standard-
Setting
As pointed out above, we consider that vocational and tractor vehicles share the same
engine hardware with 455hp and 350hp rating, since the same engines would likely be applied to
both tractor and vocational sectors, consistent with the current market structure. However,
moving to 2021, and 2024 and 2027 years, those maps between tractor and vocational vehicles
could start to deviate, even though the engine hardware remains the same, because of different
technology paths. Since the benefits obtained from WHR would be minimal for vocational
applications, we do not expect that WHR would be used in this sector (and the vocational vehicle
standards consequently do not reflect any use of engines with WHR). On the other hand,
transient control technology is one of the major enabling technologies in the vocational sector.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
In addition, the weighting of the composite certification cycles is much higher in the transient
cycle than in the 55 mph and 65 mph cruise speed cycles. In the vehicle standard-setting
process, we use the steady state map for the 55 and 65 mph cruise speed cycles, while the cycle
average maps are used for transient ARB cycle. The technology effectiveness map without
WHR and transient control technology is used to develop an engine fuel map for 55 and 65mph
cycles, where the same principle of engine fuel map from the tractor vehicle described in Chapter
2.8.4 is used. The second map is for the transient ARB cycle, where the total reduction of
technology effectiveness map without WHR but with transient control technology is used for the
cycle average map. After two maps are created, a weighting factor derived from three weighting
factors of 55mph, 65mph cruise speed cycles and transient ARB cycle is used to determine the
final reduction of emissions. For the sake of simplicity, it is noted that engines with 455hp and
350hp are the same ones as the tractor engines largely with the same technology path, and
therefore they can be grouped together by using one unique mapping methodology. On the other
hand, the engine with 200 hp and 270 hp for Class 2b-7 vehicles can be grouped into a second
group by using another set of mapping procedures, since the agencies used a different technology
path for these than for tractor engines.
Compared to the tractor engine technology table (Table 2-11) or with potential new
engine platform, the SET weighted reductions are identical except WHR setting to zero, and a
technology called model based control for transient operations is added. It is also noted that
market penetrations are different from Table 2-12. This is because new engine calibrations must
be developed without the WHR device, and portions of new engine platform may be less likely
applied to vocational sectors as opposed to the tractor market. Again, this is just one of the
technology paths proposed, and there could be many other ways to achieve the same goal. It is
also noted that the total reduction from each table is different, with more reductions predicted
from transient control than for control under steady state conditions. This reflects a different
technology path for each, and, specifically, that model based control for the transient operation
can play a significant role in reducing vehicle CO2 emissions.
The maps reflect that certain additional benefits from engine improvements can
appropriately be included in the vehicle standard, specifically, improvements based on will total
and more optimal integration between engine and transmission during transient operation. (As
explained in 2.8 above, the same approach is reflected with respect to engine improvements in
the tractor standard).
We next used these steady state and transient technology maps to translate the reductions
into the engine fuel maps used for GEM during the stringency standard runs. Figure 2-40
highlights the principle of the final mapping procedure. In this figure, SS stands for steady state.
Starting with the 2018 baseline engine fuel map (the top of this figure), the baseline cycle
average map is created with a 1.05 transient correction factor, which is used to multiply the fuel
rate obtained from a normal GEM simulation with a steady state engine fuel map. How the cycle
average map is created can be seen in Chapter 3 of the RIA. The transient factor of 1.05 is
derived from a large experimental data set to account for transient behavior. Next, 2018 baseline
technology maps, such as Figure 2-20 and Figure 2-21, are used to generate steady state engine
fuel maps for 2021, 2024, and 2027, following the exactly same procedure for HHD engines as
the tractor engine fuel maps, and the same procedure for Class 2b-7 as vocational engines (i.e.,
engines used in vocational vehicles). The cycle average maps for 2021, 2024, and 2027 will be

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review **'
generated based on the new derived cycle average multiplier as shown in Table 2-53 and Table
2-54.
1.05 transient correction
2018 map
Cycle Average map
SS Map
Reduction
Cycle average multiplier
SS 21/24/27
maps
Cycle Average
21/24/27 maps
Figure 2-40 Vocational engine fuel map for GEM run
The cycle average multipliers are shown in the table below, which are calculated by
subtracting the difference between the transient technology map reduction and the SS technology
map reduction from 1.05.
Table 2-53 Cycle Average Multiplier for HHD Engines
YEARS
SS TECHNOLOGY MAP
REDUCTION USED IN
GEM
TRANSIENT TECHNOLOGY
MAP REDUCTION USED IN
CYCLE AVERAGE MAP
CYCLE
AVERAGE
MULTIPLIER
2021
2.0%
2.8%
1.042
2024
3.4%
4.8%
1.036
2027
3.9%
5.5%
1.034
Table 2-54 Cycle Average Multiplier for LHD and MHD Engines
YEARS
SS TECHNOLOGY MAP
REDUCTION USED IN
GEM
TRANSIENT TECHNOLOGY
MAP REDUCTION USED IN
CYCLE AVERAGE MAP
CYCLE
AVERAGE
MULTIPLIER
2021
1.8%
2.6%
1.043
2024
3.4%
4.4%
1.036
2027
3.5%
5.2%
1.033
The overall reduction over the composite cycles differ as a result of combining steady
state mapping with transient mapping for the final vehicle stringency standard runs using GEM.
It should be between the total reduction shown in the steady state technology map and transient
technology maps. Since more aggressive model based control for transient operation is used in

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
the vehicle standards than for the engine standards, it can be expected that overall reduction
would be more than engine standards, which vehicle standard is in the range of 4.8 percent on
average over all vocational vehicles.
With the engine fuel map procedure developed, all vocational engine fuel maps can be
created. Figures shown below are the engine fuel maps used for vocational vehicles from 2021
to 2027, including 455hp, 350hp, 270hp, and 200hp engines.
2021 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
1 1200

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review
2021 Engine 270hp / 7L BSFC ( g / kW * hr)
900
800
700
600
500
Q)
F 400
o
H
300
230
245
200
265
100
800 1000 1200 1400 1600 1800 2000 2200 2400 2600
Speed ( RPM )
Figure 2-43 2021 Vocational Engine Fuel Map with 270hp Rating
2021 Engine 200hp / 7L BSFC ( g / kW * hr)
900
800
700
600
500
o
F 400
o
I—
300
230
245
265
2.65
230
245
265
200
100
800 1000 1200 1400 1600 1800 2000 2200 2400
Speed ( RPM )
Figure 2-44 2021 Vocational Engine Fuel Map with 200hp Rating

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review
2024 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
Z 1200
5. 1000
800
600
200
210
230
400
230
200
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-45 2024 Vocational Engine Fuel Map with 455hp Rating
2024 Engine 350hp/11L BSFC ( g / kW * hr)
1600
1400
1200
1000
E
z
ง 800
w
o
i—
600
1\ 5
400
200
600 800 1000 1200 1400 1600 1 800 2000 2200
Speed ( RPM)
Figure 2-46 2024 Vocational Engine Fuel Map with 350hp Rating

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review
2024 Engine 270hp / 7L BSFC ( g / kW * hr)
900
800
700
600
E
z
500
0)
F 400
o
i—
300
240
200
260
260
100
800 1000 1200 1400 1600 1800 2000 2200 2400 2600
Speed ( RPM)
Figure 2-47 2024 Vocational Engine Fuel Map with 270hp Rating
2024 Engine 200hp / 7L BSFC ( g / kW * hr)
900
800
700
600
E
Z
500
<1>
F 400
O
I-
300
^15"
225
240
260
-285"
225
240
260
200
100
800 1000 1200 1400 1600 1800 2000 2200 2400
Speed ( RPM)
Figure 2-48 2024 Vocational Engine Fuel Map with 200hp Rating

-------
E. O. 12866 Review - Revised - Do Not Cite, Quote, or Release During Review
2027 Engine 455hp / 15L BSFC ( g / kW * hr)
2000
1800
1600
1400
Z 1200
1000
800
600
200
210
225
400
225
200
600
800
1000 1200 1400 1600 1800 2000 2200
Speed ( RPM )
Figure 2-49 2027 Vocational Engine Fuel Map with 455hp Rating
2027 Engine 350hp / 11L BSFC ( g / kW * hr)
1600
1400
1200
1000
E
Z
o
3
D-
800
o
I—
600
400
200
600 800 1000 1200 1400 1600 1800 2000 2200
Speed ( RPM)
Figure 2-50 2027 Vocational Engine Fuel Map with 350hp Rating

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2027 Engine 270hp / 7L BSFC ( g / kW * hr)
- 260
800 1000 1200 1400 1600 1800 2000 2200 2400 2600
Speed ( RPM)
Figure 2-51 2027 Vocational Engine Fuel Map with 270hp Rating
2027 Engine 200hp / 7L BSFC ( g / kW * hr)
800 1000 1200 1400 1600 1800 2000 2200 2400
Speed ( RPM)
Figure 2-52 2027 Vocational Engine Fuel Map with 200hp Rating
2.9.2 Defining Baseline Vocational Vehicles
As at proposal, the agencies are subcategorizing the vocational vehicle sector by use of
three gross vehicle weight classes and three distinct test cycles. Also as proposed, these duty
cycles are termed Regional, Multipurpose, and Urban. However, the agencies have made

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
significant changes to these duty cycles as well as changes to the specifications of vehicles that
are considered as part of the baseline for each of these subcategories. For the establishment of
three duty cycle-based subcategories, the agencies are relying on work conducted by the U.S.
Department of Energy at the National Renewable Energy Laboratory (NREL) that grouped
vehicles with similarities of key driving statistics into three clusters of operation. NREL's
methodology and findings are described in a report in the docket for this rulemaking,148
For development and refinement of the certification test cycles, the agencies have
considered NREL's work as well as public comment and engineering judgment. Details on how
the agencies established weightings of the different test cycles for each subcategory are
presented in the RIA Chapter 3.4.3. Figure 2-53 illustrates vehicles in NREL's fleet DNA
database plotted according to similarities in their driving statistics. In this image, the two clusters
identified in a prior exercise are joined by a middle cluster that contains vehicle traces that do not
clearly fall into either the left (slower) or right (faster) cluster. Each point represents one day of
driving in the entire data set. Points are colored according to their optimized cluster placement.
Trace Clustering - 8 Metrics (3 Clusters)
2-
0
Q.
1	o-
o
_a>
Q.
o











pet zerdฎ
, o ซpeed std
I
•
speed avg










-7.5
-5
.0
-2.5
0.0
2.5
slo
Principle Component 1
Figure 2-53 Three operational clusters observed by NREL
Consistent with the number of Phase 2 subcategories, nine baseline vocational vehicle
configurations have been developed for those powered by CI engines, plus six configurations for
vocational vehicle powered by SI engines, plus seven custom chassis baseline configurations.
Vocational vehicle attributes set by the agencies in both the baseline and in the executable
version of the GEM include: transmission gear efficiencies, transmission inertia, engine inertia,
axle efficiency, number of axles, axle inertia, axle efficiency, electrical and mechanical

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
accessory power demand, vehicle mass and payload, and aerodynamic cross-section and drag
coefficient. Other vehicle attributes that are available as user inputs for compliance purposes and
for which we have established baseline values include: engine power and displacement (and
multi-point fuel map), axle ratio, transmission type and gear ratios, and tire revs/mile.
In each of our defined baseline configurations, the agencies have not applied any vehicle-
level fuel saving or emission reduction technology beyond what is required to meet the Phase 1
standards. NHTSA and EPA reviewed available information regarding the likelihood that
manufacturers of vocational vehicles would apply technology beyond what is required for Phase
1, and we concluded that the best approach was to analyze a reference case that maintains
technology performance at the Phase 1 level. Thus, the GEM-simulated baseline vocational
vehicle configurations as well as the programmatic vocational vehicle reference case analyzed in
this rule represent what is referred to as a nominally flat baseline.
Tables 4-8, 4-9, and 4-10 in the RIA Chapter 4 present the non-user-adjustable modeling
parameters for HHD, MHD and LHD vocational vehicles, respectively. In addition to those
parameters, to completely define the baseline vehicles, the agencies also selected parameters
shown in Table 2-55 to Table 2-61. These attributes and parameters were selected to represent a
range of performance across this diverse segment, and are intended to represent a reasonable
range of vocational chassis configurations likely to be manufactured in the implementation years
of the Phase 2 program. The tire sizes and axle ratios were selected based on market research of
publically available manufacturer product specifications, as well as some manufacturer-supplied
information about configurations sold in prior model years. The transmission gear ratios were
selected based on the transmissions for which models have been validated in GEM, plus public
comments from transmission suppliers. We received public comments from Allison
recommending close transmission gear ratios for use in coach and transit buses, which we have
programmed as the default GEM transmission for these custom chassis. Considering all of the
above information, the agencies have significantly better defined vocational baselines than at
proposal. A summary of information on which we based these baselines is available in the
docket.149 In general, the trend is that vehicles with higher final drive ratios have been selected
for the subcategories with less weighting of the highway test cycles.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-55 Heavy Heavy-Duty Diesel Modeling Parameters for Vocational Vehicle Baseline
GEM PARAMETER
REGIONAL
REGIONAL
MULTI-
MULTI-
MULTI-
URBAN

(95%)
(5%)
PURPOSE
(80%)
PURPOSE
(10%)
PURPOSE
(10%)

CI Engine
2018 MY 15L
2018 MY
2018 MY 11L
2018 MY
2018 MY
2018 MY 11L

455hp Engine
11L 350 hp
engine
350 hp Engine
15L 455hp
Engine
11L 350 hp
Engine
350 hp Engine
Transmission Type
10-speed MT
6-speed AT
6-speed AT
10-speed MT
10-speed
MT
5-speed AT
Transmission Gears
12.8, 9.25,
3.51, 1.91,
4.6957, 2.213,
12.8, 9.25,
12.8, 9.25,
4.6957, 2.213,

6.76, 4.9,
1.43, 1.0,
1.5291, 1.0,
6.76,4.9,
6.76,4.9,
1.5291, 1.0,

3.58,2.61,
0.74, 0.64
0.7643,
3.58,2.61,
3.58,2.61,
0.7643

1.89, 1.38,

0.6716
1.89, 1.38,
1.89, 1.38,


1.0, 0.73


1.0, 0.73
1.0, 0.73

Torque converter lockup
3
3
3
3
3
3
gear






Drive Axle Gear Ratio
3.76
3.8
4.33
4.33
4.33
5.29
Axle Configuration
6x4
6x4
6x4
6x4
6x4
6x4
Tire Revs/mile
496
515
496
496
496
496
Steer Tires (CRR kg/metric
7.7
7.7
7.7
7.7
7.7
7.7
ton)






Drive Tires (CRR kg/metric
7.7
7.7
7.7
7.7
7.7
7.7
ton)






Electrified Accessories
0
0
0
0
0
0
Tire Pressure System
0
0
0
0
0
0
Idle Reduction
N
N
N
N
N
N
Weight Reduction (lb)
0
0
0
0
0
0

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-56 Vocational MHD SI Baseline Modeling Parameters
GEM PARAMETER
REGIONAL
MULTI-
PURPOSE
URBAN
SI Engine
2018 MY 6.8L, 300 hp engine
Transmission Type
6-speed AT
6-speed AT
5-speed AT
Transmission Gears
3.102, 1.8107, 1.4063, 1.0,0.7117,0.61
3.102, 1.8107,
1.4063, 1.0,
0.7117
Transmission
efficiency
GEM Default
Torque converter
lockup gear
3
3
3
Axle efficiency
GEM Default
Drive Axle Gear Ratio
5.5
5.1
5.1
Axle Configuration
4x2
4x2
4x2
Idle Reduction
No
Tire Revs/mile
517
557
557
Steer Tires (CRR
kg/metric ton)
7.7
7.7
7.7
Drive Tires (CRR
kg/metric ton)
7.7
7.7
7.7
Aerodynamic
Improvement
0
0
0
Electrified Accessories
0
0
0
Tire Pressure System
0
0
0
PTO Improvement
0
0
0
Weight Reduction (lb)
0
0
0

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-57 Vocational MHD Diesel Baseline Modeling Parameters
GEM PARAMETER
REGIONAL
MULTI-
PURPOSE
URBAN
CI Engine
2018 MY 7L, 270 hp Engine
Transmission Type
6-speed AT
6-speed AT
5-speed AT
Transmission Gears
3.102, 1.8107, 1.4063, 1.0,0.7117,0.61
3.102, 1.8107,
1.4063, 1.0,
0.7117
Transmission
efficiency
GEM Default
Torque converter
lockup gear
3
3
3
Axle efficiency
GEM Default
Drive Axle Gear Ratio
5.5
5.29
5.29
Axle Configuration
4x2
4x2
4x2
Idle Reduction
No
Tire Revs/mile
517
557
557
Steer Tires (CRR
kg/metric ton)
7.7
7.7
7.7
Drive Tires (CRR
kg/metric ton)
7.7
7.7
7.7
Aerodynamic
Improvement
0
0
0
Electrified Accessories
0
0
0
Tire Pressure System
0
0
0
PTO Improvement
0
0
0
Weight Reduction (lb)
0
0
0

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-58 SI Light Heavy-Duty Modeling Parameters for Vocational Baseline
GEM PARAMETER
REGIONAL
MULTI-PURPOSE
URBAN
SI Engine
2018 MY 6.8L, 300 hp engine
Transmission Type
6-speed AT
6-speed AT
5-speed AT
Transmission Gears
3.102, 1.8107, 1.4063, 1.0,0.7117,0.61
3.102, 1.8107,
1.4063, 1.0,0.7117
Transmission efficiency
GEM Default
Torque converter lockup
gear
3
3
3
Axle efficiency
GEM Default
Drive Axle Gear Ratio
4.33
4.88
4.88
Axle Configuration
4x2
4x2
4x2
Idle Reduction
No
Tire Revs/mile
680
680
660
Steer Tires (CRR kg/metric
ton)
7.7
7.7
7.7
Drive Tires (CRR kg/metric
ton)
7.7
7.7
7.7
Aerodynamic Improvement
0
0
0
Electrified Accessories
0
0
0
Tire Pressure System
0
0
0
PTO Improvement
0
0
0
Weight Reduction (lb)
0
0
0

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-59 Vocational LHD Diesel Baseline Modeling Parameters
GEM PARAMETER
REGIONAL
MULTI-
PURPOSE
URBAN
CI Engine
2018 MY 7L, 200 hp Engine
Transmission Type
6-speed AT
6-speed AT
5-speed AT
Transmission Gears
3.102, 1.8107, 1.4063, 1.0,
0.7117,0.61
3.102, 1.8107,
1.4063, 1.0,
0.7117
Torque converter lockup gear
3
3
3
Drive Axle Gear Ratio
4.33
4.56
4.56
Axle Configuration
4x2
4x2
4x2
Idle Reduction
No
Tire Revs/mile
670
670
660
Steer Tires (CRR kg/metric ton)
7.7
7.7
7.7
Drive Tires (CRR kg/metric ton)
7.7
7.7
7.7
Aerodynamic Improvement
0
0
0
Electrified Accessories
0
0
0
Tire Pressure System
0
0
0
PTO Improvement
0
0
0
Weight Reduction (lb)
0
0
0
The final baseline configurations for buses shown in Table 2-60 reflect comments from
Allison about close ratio transmission gear spreads that are common for these applications. The
transmission gear ratios for the other three types of HHD custom chassis use the same
transmission as in the HHD Urban primary subcategory. The final baseline configurations for
motor homes and school buses shown in Table 2-61 are identical to the respective baseline
configurations for MHD Regional and MHD Urban vehicles in the primary program.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-60 Custom Chassis HHD Baseline Modeling Parameters
GEM Parameter
Coach Bus
(Regional)
Refuse, Mixer,
Emergency (Urban)
Transit (urban)
CI Engine
2018 MY 11L, 350 hp Engine
Transmission Type
6-speed AT
5-speed AT
5-speed AT
Transmission Gears
3.51, 1.91, 1.43,
1.0, 0.74,0.64
4.69,2.213, 1.5291,
1.0, 0.7643
3.51, 1.91, 1.43, 1.0,
0.74
Torque converter lockup gear
3
3
3
Drive Axle Gear Ratio
4.33
5.29
5.29
Axle Configuration
6x2
6x4
4x2
Idle Reduction
No
No
No
Tire Revs/mile
496
496
517
Steer Tires (CRR kg/metric ton)
7.7
7.7
7.7
Drive Tires (CRR kg/metric ton)
7.7
7.7
7.7
Aerodynamic Improvement
0
0
0
Electrified Accessories
0
0
0
Tire Pressure System
0
0
0
PTO Improvement
0
0
0
Weight Reduction (lb)
0
0
0
Table 2-61 Custom Chassis MHD Baseline Modeling Parameters
GEM Parameter
Motor Homes
School Bus

(Regional)
(Urban)
CI Engine
2018 MY 7L, 270 hp Engine
Transmission Type
6-speed AT
5-speed AT
Transmission Gears
3.102, 1.8107,
3.102, 1.8107,

1.4063, 1.0,
1.4063, 1.0,0.7117

0.7117,0.61

Torque converter lockup gear
3
3
Drive Axle Gear Ratio
5.5
5.29
Axle Configuration
4x2
4x2
Idle Reduction
No
No
Tire Revs/mile
517
557
Steer Tires (CRR kg/metric
ton)
7.7
7.7
Drive Tires (CRR kg/metric
ton)
7.7
7.7
Aerodynamic Improvement
0
0
Electrified Accessories
0
0
Tire Pressure System
0
0
PTO Improvement
0
0
Weight Reduction (lb)
0
0

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.9.2.1 Setting Vocational Vehicle Baselines
The baseline performance of vocational vehicles powered by CI engines as described
above is shown in Table 2-62.
Table 2-62 Baseline Vocational Vehicle Performance with CI Engines
BASELINE EMISSIONS PERFORMANCE IN C02 GRAM/TON-MILE
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty Class
6-7
Heavy Heavy-Duty
Class 8
Urban
482
332
338
Multi-Purpose
420
294
287
Regional
334
249
220
Baseline Fuel Efficiency Performance in gallon per 1,000 ton-mile
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty Class
6-7
Heavy Heavy-Duty
Class 8
Urban
47.3477
32.6130
33.2024
Multi-Purpose
41.2574
28.8802
28.1925
Regional
32.8094
24.4597
21.6110
The baseline performance of vocational vehicles powered by SI engines as described
above is shown in Table 2-63.
Table 2-63 Baseline Vocational Vehicle Performance with SI Engines
BASELINE EMISSIONS PERFORMANCE IN C02 GRAM/TON-
MILE
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)
Urban
502
354
Multi-Purpose
441
314
Regional
357
275
Baseline Fuel Efficiency Performance in ga
Ion per 1,000 ton-mile
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)
Urban
56.4870
39.8335
Multi-Purpose
49.6230
35.3325
Regional
40.1710
30.9441
The baseline performance of the custom chassis configurations described above is shown
in Table 2-64.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-64 Baseline Performance of Custom Chassis
VEHICLE TYPE
EPA
NHTSA
Coach Bus
231
22.6916
Motor Home
249
24.4597
School Bus
332
32.6130
Transit
332
32.6130
Refuse
338
33.2024
Mixer
338
33.2024
Emergency
338
33.2024
2.9.2.2 Assigning Vocational Vehicles to Subcategories
In the NPRM, the agencies proposed criteria by which a vehicle manufacturer would
know in which vocational subcategory - Regional, Urban, or Multipurpose - the vehicle should
be certified. These cut-points were defined using calculations relating engine speed to vehicle
speed. Specifically, we proposed a cutpoint for the Urban duty cycle where a vehicle at 55 mph
would have an engine working above 90 percent of maximum engine test speed for vocational
vehicles powered by diesel engines and above 50 percent for vocational vehicles powered by
gasoline engines. Similarly we proposed a cutpoint for the Regional duty cycle where a vehicle
at 65 mph would have an engine working below 75 percent of maximum engine test speed for
vocational vehicles powered by diesel engines and below 45 percent for vocational vehicles
powered by gasoline engines. We received several comments that identified weaknesses in that
approach. Specifically, Allison explained that vehicles with two shift schedules would need
clarification which top gear to use when calculating the applicable cut-point. Also, Daimler
noted that, to the extent that downspeeding occurs in this sector over the next decade or more,
cutpoints based on today's fleet may not be valid for a future fleet. Allison noted that the
presence of additional top gears could strongly influence the subcategory placement of
vocational vehicles. These comments highlight the possibility of misclassification, and the
potential pitfalls in a mandated classification scheme. Furthermore, the agencies are concerned
that even if cutpoints were set that were viewed as valid in future years, manufacturers would be
able to satisfy the criteria to qualify for the regional subcategory by modifying driveline designs
slightly while maintaining customer satisfaction.
In a regulatory structure where standards for vehicles in different subcategories have
different stringencies, the agencies are inclined to prefer assigning subcategorization based on
regulatory criteria rather than allowing the manufacturers unconstrained choice. The approach to
setting of the final standards is explained in Preamble Section V.C.2.d. Below in Table 2-65 we
present our estimate of the distribution of vocational vehicles we predict will be certified in each
subcategory, as used only for estimating overall programmatic costs and benefits, not as part of
standard-setting. This estimate includes refined population distributions by weight class that
have been adjusted in part in response to comments on the draft NREL report in the NODA as
well as new analysis of telematics data from Ryder lease vehicles.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-65 Vocational Vehicle Types and Population Allocation
VEHICLE TYPE
REGIONAL
MULTI-PURPOSE
URBAN
C4-5 Short Haul Straight Truck
9%
41%
50%
C6-7 Short Haul Straight Truck
15%
50%
35%
C8 Short Haul Straight Truck
20%
60%
20%
Long Haul Straight Truck, Motor
Home, Intercity Bus
100%
0%
0%
School Bus
0%
10%
90%
Transit Bus
0%
0%
100%
Refuse
0%
10%
90%
All Class 4-5
11%
15%
18%
All Class 6-7
10%
11%
16%
All Class 8
5%
8%
6%
2.9.3Costs and Effectiveness of Vocational Vehicle Technologies
The following paragraphs describe the vehicle-level technologies on which the vocational
vehicle standards are predicated, and their projected effectiveness over the test cycles. The
methodology for estimating costs, including indirect cost estimates and learning effects, is
described in RIA Chapter 2.11.1. Certain elements of the cost estimating methodology are the
same as for the Phase 1 program, but certain elements are different including how the agencies
apply the markups, how the markups change with time, and which cost elements are influenced
by learning effects. As a result of different technology complexities, learning effects, and
different short-term and long-term warranty and non-warranty-related indirect costs, some
technology costs identified below may appear higher in MY 2021 than in MY 2027. These
differences are not due to changes in adoption rates, since the costs in Chapter 2.11 and below in
Chapter 2.9.3 to 2.9.4 are for applying a given technology to a single vehicle. Throughout this
chapter, where a dollar cost is given for a technology, note that these are adjusted to be valued as
year 2013 dollars. Average costs for vocational vehicle technology packages, including adoption
rates, are presented below in Chapter 2.9.5. Detailed descriptions of technology packages for SI
engines can be found in the RIA Chapter 2.6. Detailed descriptions of technology packages and
costs for CI engines can be found in the RIA Chapter 2.7.
2.9.3.1 Transmissions
Transmission improvements present a significant opportunity for reducing fuel
consumption and CO2 emissions from vocational vehicles. Transmission efficiency is important
for many vocational vehicles as their duty cycles involve high percentages of driving under
transient operation. The types of transmission improvements the agencies considered for Phase 2
are advanced shift strategy, gear efficiency, torque converter lockup, architectural improvements,
and hybrid powertrain systems.
Of the technologies described above in Chapter 2.4, the agencies are predicating the
vocational vehicle standards in part on performance improvements achieved by use of advanced
transmissions as described in Table 2-66, below. The projected market adoption rates that
inform the technology packages are described in Chapter 2.9.5.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-66 Projected Vocational Transmission Improvements over GEM Baseline
TRANSMISSION
PROJECTED

REGIONAL
MULTI-PURPOSE
URBAN
TECHNOLOGY
IMPROVEMENT OVER
COMPOSITE
COMPOSITE CYCLE
COMPOSITE

TEST CYCLE3

CYCLE

CYCLE
Two More Gears
ARB Transient
1.0%
1.7
1.2
0.9

55 mph Cruise
2.0%




65 mph Cruise
2.0%



Torque Converter
ARB Transient
1-5%
0.7 to 0.9
0.9 to 2.2
0.8 to 3.2
Lockup in 1st Gear (vs
55 mph Cruise
0%



3rd)
65 mph Cruise
0%



Non-Integrated Mild
ARB Transient
14%
3
8
11-12
Hybrid
55 mph Cruise
0%




65 mph Cruise
0%



Integrated Mild
ARB Transient
23-
4-5
14-19
19-25
Hybrid with Stop-Start

26%




55 mph Cruise
0%




65 mph Cruise
0%



Advanced Shift
ARB Transient
7%
3
4-5
5-6
Strategy
55 mph Cruise
2%




65 mph Cruise
2%



Note:
a Technology improvements modeled in GEM are TC lockup and gear number. Hybrids and shift strategy require separate
testing.
2.9.3.1.1 Advanced Shift Strategy
The technology we described at proposal as driveline integration, 80 FR 40296, is now
defined as use of an advanced shift strategy. At proposal the agencies included shift strategy,
aggressive torque converter lockup, and a high efficiency gearbox among the technologies
defined as driveline integration that would only be recognized by use of powertrain testing. The
agencies continue to believe that an effective way to derive efficiency improvements from a
transmission is by optimizing it with the engine and other driveline components to balance both
performance needs and fuel savings. One example of an engine manufacturer partnering with a
transmission manufacturer to achieve an optimized driveline is the SmartAdvantage
powertrain.150 Using engineering calculations to estimate the benefits that can be demonstrated
over the powertrain test, the agencies project that transmission shift strategies, including those
that make use of enhanced communication between engine and driveline, can yield efficiency
improvements ranging from three percent for Regional vehicles to nearly six percent for Urban
vehicles. The calculation is an energy-weighted and cycle-weighted average improvement using
cycle-specific CO2 emissions reported in the GEM output file for baseline vehicles. For the idle
cycles, the development version of GEM provides emissions in grams per hour. For the driving
cycles, GEM provides emissions in grams per ton-mile. By multiplying those values by the
average speed of each cycle and the default payload, all values are converted to grams per hour,
and these are surrogates for the energy expended over those cycles. For example, in the medium
heavy-duty Multipurpose subcategory with a payload of 5.6 tons, the baseline vehicle
configuration has cycle-specific results of 28,000 g CCh/hr for the transient cycle, 59,000 for the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
55 cycle, 85,000 for the 65 cycle, 8,500 for drive idle, and 3,700 for parked idle. By summing
the products of the percent improvement expected over each cycle, the CO2 emitted while
completing the cycle, and the associated composite weighting of the cycle, and dividing by the
sum of the products of the CO2 emitted and cycle weightings, we obtain results shown in Table
2-66. See the RIA Chapter 3.6 for a discussion of the powertrain test procedure.
The agencies have revised the GEM simulation tool to recognize additional transmission
technologies beyond what was possible at proposal. We are adopting a transmission efficiency
test to recognize improved mechanical gear efficiency and reduced transmission friction, where
the test results can be submitted as GEM inputs to override the default efficiency values. The
agencies project that vehicle fuel efficiency can be improved by up to one percent from
improved transmission gear efficiency, which we are projecting to be the same during each of the
driving cycles and (necessarily) zero while idling. Actual test results are likely to show that
some gears have more room for improvement than others, especially where a direct drive gear is
already highly efficient. Using the energy-weighted calculation method described above, the
transmission gear efficiency improvement used in our stringency calculations ranges from 0.82
to 0.97 percent. Final GEM also accepts an input field for torque converter lockup gear. As a
default, GEM simulates automatic transmissions using lockup in third gear. Using the library of
agency transmission files, GEM gives a different effectiveness value in every vocational vehicle
subcategory, because this is influenced by the gear ratios, drive cycle, and torque converter
specifications. Manufacturers will obtain slightly different results with their own driveline
specifications. The observed range of cycle-weighted effectiveness of torque converter lockup is
from less than one percent to three percent, as shown in Table 2-66 above.
Based on use of a sensor, the agencies estimate the total cost to apply an advanced shift
strategy for driveline integration is $87 in MY 2021 and $73 in MY 2027, as described in RIA
2.11.3.7. The agencies have also estimated capital and operational costs associated with building
test cells and conducting testing, as well as research and development costs associated with
designing shift strategies and integrating drivelines. These costs are presented in the RIA Chapter
7.1.1.2 and 7.1.1.3, respectively. The agencies estimate the total cost to apply a high efficiency
gearbox is $315 in MY 2021 and $267 in MY 2027, as described in RIA 2.11.3.5. The agencies
estimate the total cost to apply early torque converter lockup to a vocational vehicle at $31 in
MY 2021 and $26 in MY 2027, as described in RIA 2.11.3.6.
2.9.3.1.2 Architectural Transmission Improvements
One type of architectural improvement the agencies project can reasonably be developed
by manufacturers of all transmission architectures is increased number of gears. The benefit of
adding more gears varies depending on whether the gears are added in the range where most
operation occurs. In some cases additional gears in the low end of the range enhances driving
performance without improving fuel efficiency. The TIAX 2009 report projected that 8-speed
transmissions could incrementally reduce fuel consumption by 2 to 3 percent over a 6-speed
automatic transmission, for Class 3-6 box and bucket trucks, refuse haulers, and transit buses.151
We have run GEM simulations comparing 5-speed, 6-speed, 7-speed, and 8-speed automatic
transmissions where some cases hold the total spread constant, some hold the high end ratio
constant, and some hold the low-end ratio constant, where all cases use a third gear lockup and
axle ratios are held constant. We have observed mixed results, with some improvements over the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
highway cruise cycles as high as six percent, and some cases where additional gears increased
fuel consumption. As proposed, we are allowing GEM to determine the improvement, where
manufacturers will enter the number of gears and gear ratios and the model will simulate the
efficiency over the applicable test cycle. The agencies have revised GEM based on comment,
and we are confident that it fairly represents the fuel efficiency of transmissions with different
gear ratios. Consistent with literature values, we are using engineering calculations to estimate
that two extra gears has an effectiveness of one percent improvement during transient driving
and two percent improvement during highway driving. Weighting these improvements using our
final composite duty cycles (zero improvement at idle) and the energy-weighting method
described above, this technology is estimated to improve vocational vehicle efficiency between
0.9 and 1.7 percent. The agencies estimate the total cost to add two gears to a vocational vehicle
transmission at $504 in MY 2021 and $465 in MY 2027, as described in RIA 2.11.3.1.
Most vocational vehicles currently use torque converter automatic transmissions (AT),
especially in Classes 2b-6. Automatic transmissions offer acceleration benefits over drive cycles
with frequent stops, which can enhance productivity. With the diversity of vocational vehicles
and drive cycles, other kinds of transmission architectures can meet customer needs, including
automated manual transmissions (AMT), dual clutch transmissions (DCT), as well as manual
transmissions (MT).152 As at proposal, dual clutch transmissions may be simulated as AMT's in
GEM. A manufacturer may elect to conduct powertrain testing to obtain specific improvements
for use of a DCT. The RIA Chapter 4.2.2.3 explains the EPA default shift strategy and the losses
associated with each transmission type, and discusses changes that have been made since
proposal. Although the representation of transmissions has improved since proposal, the
differences between AT and AMT are too difficult to isolate for purposes of figuring them into
our stringency calculations. Although we expect manufacturers to have a reasonable model of
transmission behavior for certification purposes, we could not estimate relative improvement
values between AT and AMT for vocational vehicles using any defensible estimation method.
The agencies have not been able to obtain conclusive data that could support a final vocational
vehicle standard, in any subcategory, predicated on adoption of an AMT or DCT with a
predictable level of improvement over an AT. As a result, the only architectural changes on
which the final vocational vehicle standards are based are increasing number of gears and
automation compared with a manual transmission. The final Phase 2 GEM has been calibrated to
reflect a fixed two percent difference between manual transmissions and automated
transmissions during the driving cycles (zero at idle). As in the HHD Regional subcategory
baseline, manual transmissions simulated in GEM perform two percent worse than similarly-
geared AMT. This fixed improvement is discussed further in RIA Chapter 2.4. The agencies
have estimated the cost of upgrading from HHD manual transmissions to AMT at $4,540 in MY
2021 and $3853 in MY 2027, as described in RIA 2.11.3.2.
2.9.3.1.3 Hybrid Drivelines
Hybrid drivelines are included under transmission technologies because, depending on
the design and degree of hybridization, they may either replace a conventional transmission or be
deeply integrated with a conventional transmission. Further, these systems are often
manufactured by companies that also manufacture conventional transmissions.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The agencies are including hybrid powertrains as a technology on which some of the
vocational vehicle standards are predicated, in part.
After considering comments, the agencies are projecting adoption of two types of mild
hybrids, defined using system parameters based on actual systems commercially available in the
market today.153 Some mild hybrid systems will be integrated with an engine sufficient to enable
use of an engine stop-start feature, while some mild hybrids will not be integrated and will only
provide transient benefits related to regenerative braking. We also have reconsidered our
effectiveness estimation method as a result of comments. Instead of relying on previously
published road tests over varying drive cycles, we are applying engineering calculations to
account for defined hybrid system capacities and inefficiencies over our certification test cycle.
We are using a spreadsheet model that calculates the recovered energy of a hybrid system using
road loads of the default baseline GEM vehicles over the ARB Transient test cycle.154
The inputs to this spreadsheet model include maximum hybrid system power, battery
capacity, allowable swing in the battery state of charge, system efficiencies, as well as vehicle
road loads such as tire rolling resistance, vehicle mass and aerodynamic drag area. For stringency
purposes, the system inputs used were 75 kW motor, 8 kWh battery, and 10 percent swing in
SOC. The system efficiencies included 90 percent, 90 percent, 90 percent, 92 percent and 85
percent, for the battery, power electronics, electric motor, axle and transmission, respectively.
The vehicle road loads were identical to those in the baseline GEM vehicle configurations.
Within the system constraints the algorithm stores and releases the available kinetic energy from
the vehicle without any information of engine efficiency through the cycle. The calculations also
take into account the energy that is needed to drive the accessories through the drivetrain when
the vehicle is decelerating. The algorithm is iterative, and the calculations continue until the
battery net energy change is at a value less than one percent of the total fuel energy which is
approximated by 3 times the total tractive work of the cycle.
One simplification in the spreadsheet model is that the effectiveness is assumed to be
zero for the highway cruise cycles. In the real world there are driving conditions on highways
that may present opportunities to capture and re-use energy, including conditions related to road
grade and congestion. However, for this simplified method we are not counting the benefits of
systems that make use of such opportunities. We are not projecting substantially less
effectiveness for heavier vehicles than for lighter vehicles, even though the same systems were
assessed for all weight classes (not scaled up for heavier vehicles). This is due in part to the
assumptions about the fraction of brake energy that enters the hybrid system vs the fraction that
goes entirely to friction braking.
Using this spreadsheet model and system inputs described above, for the non-integrated
mild hybrids, we are estimating a one to 12 percent fuel efficiency improvement over the
powertrain test, depending on the duty cycle (i.e. Regional, Urban, or Multi-purpose) in GEM for
the applicable subcategory. For the integrated mild hybrids, we have projected that the systems
are scaled up for heavier vehicles, and we have combined the effectiveness calculated using the
hybrid spreadsheet model with the GEM effectiveness of stop-start, described below. These
combined effectiveness values range from four to 25 percent for the mild hybrids with stop-start.
Even though the actual improvement from hybrids in Phase 2 will be evaluated using the
powertrain test, because the model uses the same vehicle test cycle and conservative estimates of

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
realistic configurations, the agencies have concluded it is reasonable to use these spreadsheet-
based estimates as a basis for setting stringency in the final rules.
The industry is currently developing many variations of hybrid powertrain systems.
There are a few hybrid systems in the heavy-duty market today and several more under
development, as evidenced by several public comments on this rulemaking. See also Chapter
6.3.3 of the Response to Comments document. In addition, energy storage systems are getting
better.155 Heavy-duty customers are getting used to these systems with the number of
demonstration products on the road. A list of hybrid manufacturers and their products intended
for the vocational market is provided in Table 2-67.
Table 2-67 Examples of Hybrid Manufacturers
MANUFACTURER
PRODUCT
EXAMPLE APPLICATION
Hino
Class 5 cab-over-engine battery-
electric hybrid
Delivery Trucks
Allison
HHD parallel hybrid
Transit Bus
BAE
HHD series or parallel hybrid
Transit Bus
XL
Class 3-4 mild electric hybrid
Shuttle Bus
Crosspoint Kinetics
Class 3-7 mild electric hybrid
Delivery trucks, shuttle buses
Lightning Hybrids
Class 2-5 hydraulic hybrid
Delivery trucks
Parker Hannifin
MHD hydraulic hybrid
Delivery trucks
Freightliner Custom Chassis
MHD hydraulic hybrid
Delivery trucks
Morgan Olson
MHD hydraulic hybrid
Delivery trucks
Autocar-Parker
Runwise hydraulic hybrid
Refuse Trucks
Eaton3
HHD parallel electric hybrid
Trucks and Buses
Odyne
Plug-in electric hybrid, E-PTO
Utility Trucks
Note:
a Currently selling in markets outside the U.S.
The agencies estimate the total cost of a bolt-on, non-integrated mild hybrid system for
any size vocational vehicle at $8,906 in MY 2021 and $6,906 in MY 2027. The agencies
estimate the total cost of an integrated mild hybrid system with stop-start for a LHD vocational
vehicle is $6,320 in MY 2021 and $5,082 in MY 2027. For a MHD vocational vehicle, the total
cost of an integrated system is estimated at $9,934 in MY 2021 and $7,989 in MY 2027. For a
HHD vocational vehicle, the total cost of an integrated system is estimated at $16,590 in MY
2021 and $13,341 in MY 2027, as described in RIA 2.11.7. The estimated higher costs for
heavier vehicles are related to higher power demands and greater energy storage needs. These
estimates assume no engine downsizing in the design of hybrid packages. This is in part to be
conservative in our cost estimates, and in part because in some applications a smaller engine may
not be acceptable if it would risk that performance could be sacrificed during some portion of a
work day.
2.9.3.2 Axles
The agencies are predicating part of the stringency of the final vocational vehicle
standards on performance of two types of axle technologies. The first is advanced low friction
axle lubricants and efficiency as demonstrated using the separate axle test procedure described in

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
the RIA Chapter 3.8 and 40 CFR 1037.560. The agencies received many adverse comments on
the proposal to assign a fixed 0.5 percent improvement for this technology. In consideration of
comments, the agencies are assigning default axle efficiencies to all vocational vehicles.
Manufacturers may submit test data to over-ride these default axle efficiency values in GEM.
Based on comments from axle suppliers as well as other available data, we project the
effectiveness of technologies to improve axle efficiency can achieve between two and three
percent improvement.156 Our cost analysis for the final rulemaking includes maintenance costs
of replacing axle lubricants on a periodic basis. Based on supplier information, some advanced
lubricants have a longer drain interval than traditional lubricants. We are estimating the axle
efficiency & lubricating costs for HHD to be the same as for HHD tractors since those vehicles
likewise typically have three axles. For HHD vocational vehicles (with 3 axles), the agencies
estimate the cost at $200 in MY 2021 and $174 in MY 2027, as described in RIA 2.11.5.4.
However, for LHD and MHD vocational vehicles, we scaled down the cost of this technology to
reflect the presence of a single rear axle. The agencies estimate the total cost of improved axle
efficiency on a LHD or MHD vocational vehicle (with 2 axles) at $134 in MY 2021 and $116 in
MY 2027.
The second axle technology applies only for HHD vocational vehicles, which typically
are built with two rear axles. Part time 6x2 configuration or axle disconnect is a design that
enables one of the rear axles to temporarily disconnect or otherwise behave as if it's a non-driven
axle. The agencies proposed to base the HHD vocational vehicle standard on some use of both
part time and full time 6x2 axles. The agencies received compelling adverse comment on the
application of the permanent 6x2 configuration for vocational vehicles, and in response we are
not basing the final vocational vehicle standards on any adoption of full time 6x2 axles. The
disconnect configuration is one that keeps both drive axles engaged only during some types of
vehicle operation, such as when operating at construction sites or in transient driving where
traction especially for acceleration is vital. Instead of calculating a fixed improvement as at
proposal, the agencies have refined GEM to recognize this configuration as an input, and the
benefit will be actively simulated over the applicable drive cycle. Effectiveness based on
simulations with EPA axle files is projected to be as much as 1.2 percent for HHD Regional
vehicles. Further information about this technology is provided in RIA Chapter 2.4.
The agencies estimate the total cost of part time 6x2 on a vocational vehicle at $121 in
MY 2021 and $117 in MY 2027, as described in RIA 2.11.5.2.
2.9.3.3 Lower Rolling Resistance Tires
Tires are the second largest contributor to energy losses of vocational vehicles, as found
in the energy audit conducted by Argonne National Lab.157 The two most helpful sources of data
in establishing the projected vocational vehicle tire rolling resistance levels for the final Phase 2
standards are the comments from RMA and actual certification data for model year 2014. At
proposal, we projected that all vocational vehicle subcategories could achieve average steer tire
coefficient of rolling resistance (CRR) of 6.4 kg/ton and drive tire CRR of 7.0 kg/ton by MY
2027. These new data have informed our analysis to enable us to differentiate the technology
projections by subcategory. The RMA comments included CRR values for a wide range of
vocational vehicle tires, for rim sizes from 17.5 inches to 24.5 inches, for steer/all position tires
as well as drive tires. The RMA data, while illustrating a range of available tires, are not sales

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
weighted. The 2014 certification data include actual production volumes for each vehicle type,
thus both steer and drive tire population-weighted data are available for emergency vehicles,
cement mixers, school buses, motor homes, coach buses, transit buses, and other chassis cabs.
The certification data are consistent with the RMA assessment of the range of tire CRR currently
available. We also agree with RMA's suggestion to set a future CRR level where a certain
percent of current products can meet future GEM targets. We disagree with RMA that the MY
2027 target should be a level that 50 percent of today's product can meet. With programmatic
averaging, such a level would mean essentially no improvements overall from tire rolling
resistance, because today when manufacturers comply on average, half their tires are above the
target and half are below. Further, with Phase 2 GEM requiring many more vehicle inputs than
tire CRR, manufacturers have many more degrees of freedom (i.e. other available compliance
pathways) to meet the performance standard than they do in Phase 1. In these final rules, the
agencies are generally projecting adoption of LRR tires in MY 2027 at levels currently met by 25
to 40 percent of today's vocational products, on a sales-weighted basis.158 Figure 2-54 and
Figure 2-55 present a summary of the CRR levels of tires fitted on vocational vehicles certified
in the 2014 model year.
MY 2014 Vocational Drive Tires
16 ?
14 j
12 ^
ฆ Max a90%-ile I Avg ฆ25%-ile BMin
Figure 2-54 Vocational Drive Tire CRR Data Summary

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
MY 2014 Vocational Steer Tires
16 i
14 j
12 ^
ฆ Max a90%-ile I Avg ฆ25%-ile BMin
Figure 2-55 Vocational Steer Tire CRR Data Summary
The agencies acknowledge there can be tradeoffs when designing a tire for reduced
rolling resistance. These tradeoffs can include characteristics such as wear resistance, cost and
scuff resistance. NHTSA, EPA, and ARB met with stakeholders from the tire industry
(Bridgestone, Continental, Cooper, Goodyear, and Michelin) to discuss the next generation of
lower rolling resistance (LRR) tires for the Phase 2 timeframe for all segments of Class 2b-8
vehicles, including trailers. Manufacturers discussed forecasts for rolling resistance levels and
production availability in the Phase 2 timeframe, as well as their plans for improving rolling
resistance performance while maintaining other performance parameters such as traction,
handling, wear, mass reduction, retreadability, and structural durability.
The meetings included specific discussions of the impacts of the current generation of
LRR tires on vehicle stopping distance and handling. Manufacturers indicated no known safety
detriment in the current on-road fleet from use of LRR tires. While the next generation of tires
may require some tradeoffs in wear performance and costs over the next 10 years to achieve
better tire rolling resistance performance, manufacturers said they will not trade off safety for
performance. They also emphasized that keeping tires inflated (through proper maintenance or
automatic systems) was the best way to assure long term fuel efficiency and safety during
vehicle operation.
In these final rules, we are differentiating the improvement level by weight class and duty
cycle, recognizing that heavier vehicles designed for highway use can generally apply tires with
lower rolling resistance than other vehicle types, and will see a greater benefit during use. In the
Preamble at Section V.C.I, Table V-14, the agencies define five levels of CRR for purposes of
estimating the manufacturing costs associated with applying improved tire rolling resistance to
vocational vehicles. None of the rolling resistance levels projected for adoption in MY 2027 are
lower than the 25th percentile of tire CRR on actual vocational vehicles sold in MY 2014. Thus,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
we believe the improvements will be achievable without need to develop new tires not yet
available.
As an example of the total vehicle costs to apply LRR tires, the agencies estimate the
total cost to fit a LHD or MHD vocational vehicle with two LRR level 5v steer tires ($57) and
four level 3v drive tires ($107) to be $164 in MY 2021. Detailed tables of LRR tire costs in each
year are provided in RIA Chapter 2.11.8.
As proposed, the agencies will continue the light truck (LT) tire CRR adjustment factor
that was adopted in Phase 1. 80 FR 40299; see generally 76 FR 57172-57174. In Phase 1, the
agencies developed this adjustment factor by dividing the overall vocational test average CRR of
7.7 by the LT vocational average CRR of 8.9. This yielded an adjustment factor of 0.87.
Because the MY 2014 certification data for LHD vocational vehicles may have included some
CRR levels to which this adjustment factor may have already been applied, and because we did
not receive adverse comment on our proposal to continue this, the agencies have concluded that
we do not have a basis to discontinue allowing the measured CRR values for LT tires to be
multiplied by a 0.87 adjustment factor before entering the values in the GEM for compliance.
2.9.3.4 Workday Idle Reduction
The Phase 2 idle reduction technologies considered for vocational vehicles are those that
reduce workday idling, unlike the overnight or driver rest period idling of sleeper cab tractors.
Idle reduction technology is one type of technology that is particularly duty-cycle dependent. In
light of new information, the agencies have learned that our proposal had mischaracterized the
idling operation of vocational vehicles, significantly underestimating the extent of this mode of
operation, and incorrectly calculating it using a drive idle cycle when significant idling also
occurs while parked. As described in Preamble Section V.B.I, in these final rules we have
revised our test cycles to better reflect real world idle operation, including both parked idle and
drive idle test conditions. The RIA Chapter 3.4.2 describes these certification test cycles.
The Phase 1 composite test cycle for vocational vehicles includes a 42 percent weighting
on the ARB Transient test cycle, which comprises nearly 16 percent of idle time. However, no
single idle event in this test cycle is longer than 36 seconds, which is not enough time to
adequately recognize the benefits of idle reduction technologies.1^ In the Phase 2 proposal, we
applied composite test cycle weightings of 10, 20, and 30 percent of a drive idle cycle to the
Regional, Multipurpose and Urban duty cycles, respectively. These weightings were an initial
estimate because the interagency agreement between EPA and DOE-NREL to collaborate to
characterize workday idle among vocational vehicles was not yet complete. As shown in Table
2-68, the average total amount of daily total idle operation per vehicle identified by NREL is 25
percent for vehicles observed in the high speed cluster, 47 percent for vehicles observed in the
slow speed cluster, and 52 percent for vehicles straddling those two clusters. This work was
shared as part of the NODA and supported by commenters. Although some comments indicated
individual fleets log different idle times than those in our test cycles, the final test cycles are
L However, as noted above, emission improvements due to workday idle technology can be recognized under Phase
1 as an innovative credit under 40 CFR 1037.610 and 49 CFR 535.7.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
representative of the range of operation and adequately capture vocational vehicle idle behavior
for purposes of recognizing workday idle reduction technology.
Table 2-68 Summary of Out-of-Gear Idle Behavior
NREL
Cluster
Operating Mode
NREL
Percent of
Workday
Percent
Accounted
for in Final
Transient
Cycle
Final
Weighting of
Parked Idle
Cycle
Final
Weighting
of Drive
Idle Cycle
Sum Of All
Regulatory Idle
Test Weighings
1
Out of Gear Idle
28

25


1
In Gear (Drive Idle)

10

15

1
Zero Speed (both in
gear and out of
gear)
47



50
2
Out of Gear Idle
22

25


2
In Gear (Drive Idle)

8

17

2
Zero Speed (both in
gear and out of
gear)
52



50
3
Out of Gear Idle
25

25


3
In Gear (Drive Idle)

6

0

3
Zero Speed (both in
gear and out of
gear)
25



25
The separate drive idle cycle supplements the drive idle that occurs during the transient
cycle. The time fraction of drive idle represented in the transient cycle is a complex iterative
equation because that is a distance-based cycle. By setting a total target zero-speed time of 50
percent for Multipurpose and Urban vehicles consistent with the recommendations of NREL, the
agencies were able to assign appropriate cycle weightings to the drive idle and parked idle test
cycles for each subcategory. In the final rules, the Regional duty cycle has 25 percent composite
test cycle weighting of parked idle and zero drive idle. The Multi-purpose cycle has 25 percent
of drive and 17 percent parked idle, and the Urban cycle has 15 percent drive idle and 25 percent
parked idle. The final cycle weightings are derived from data summarizing miles accumulated
within 2 mph speed bins for representative vehicles in each cluster. Details on development of
the cycle weightings are found in the RIA Chapter 3.4.3.1 and in the vocational vehicle duty
cycle report by NREL, which is available in the docket.159
At proposal, we identified two types of idle reduction technologies to reduce workday
idle emissions and fuel consumption for vocational vehicles: neutral idle and stop-start. After
considering the new duty cycle information and the many comments received, we are basing our
final vocational vehicle standards in part on the performance of three types of workday idle
reduction technologies: neutral idle, stop-start, and automatic engine shutdown. We believe that
these technologies are effective, feasible, and cost-effective, as discussed further in this section.
Neutral idle is essentially a transmission technology, but it also requires a compatible
engine calibration. Torque converter automatic transmissions traditionally place a load on

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
engines when a vehicle applies the brake while in drive, which we call curb idle transmission
torque (CITT). When an engine is paired with a manual or automated manual transmission, the
CITT is naturally lower than when paired with an automatic, as a clutch disengagement must
occur for the vehicle to stop without stalling the engine. We did not receive adverse comment on
our proposal to include this technology in our standard-setting for vocational vehicles. The
engineering required to program sensors to detect the brake position and vehicle speed, and
enable a smooth re-engagement when the brake pedal is released makes this a relatively low
complexity technology that can be deployed broadly. Navistar commented that idle reduction
strategies must have sufficient engine, aftertreatment and occupant protections in place such that
any fuel cost savings are a net benefit for the owner/operator without compromising safety. We
agree, and for neutral idle we believe an example of an allowable override is if a vehicle is
stopped on a hill. Skilled drivers operating manual transmissions can safely engage a forward
gear from neutral when stopped on upslopes with minimal roll-back. With an AT, the vehicle's
computer would need to handle such situations automatically. In the Phase 2 certification
process, transmission suppliers will attest whether the transmission has this feature present and
active, and certifying entities will be able to enter Yes or No as a GEM input for the applicable
field. The effectiveness of this technology will be calculated using data points collected during
the engine test, and the appropriate fueling over the drive idle cycle and the transient cycle will
be used. Based on GEM simulations using the final vocational vehicle test cycles, the agencies
project neutral idle to provide fuel efficiency improvements ranging from one to seven percent,
depending on the regulatory subcategory. Details are in the docket for this rulemaking.160
Automatic engine shutdown (AES) is an engine technology that is widely available in the
market today, but has seen more adoption in the tractor market than for vocational vehicles.
Although we did not propose to include this technology, we received many comments suggesting
this would be appropriate. Some commenters may have conflated the concept of stop-start with
AES, such as a comment on stop-start asking us to consider the on-board need to power
accessories while the vehicle is in stationary mode. We believe that automatic engine shutdown
is effective and feasible for many different types of vehicles, depending on how significant a
portion of the work day is spent while parked. Most truck operators are aware of the cost of fuel
consumed while idling, and importantly, the wear on the engine due to idling. Engine
manufacturers caution owners to monitor the extent of idling that occurs for each work truck and
to reduce the oil change interval if the idle time exceeds ten percent of the work day.161
Accordingly, many utility truck operators track their oil change intervals in engine hours rather
than in miles.
NTEA provided the agencies with a report with survey results on which work truck fleets
are adopting AES with backup power, and their reasons for doing so.162 The most common
reason given in the survey is to allow an engine to shut down and still have vehicle power
available to run flashing safety lights. Some vocational vehicles also need to conduct work using
a power take-off (PTO) while stationary for hours, such as on a boom truck. The agencies are
adopting an allowable AES over-ride for PTO use. Technologies that can reduce fuel
consumption during this type of high-load idle are discussed below and in the Preamble at
V.C.l.c. We are also adopting an allowable AES over-ride if the battery state of charge drops
below a safe threshold. This would ensure there is sufficient power to operate any engine-off
accessories up to a point where the battery capacity has reached a critical point. Where a
vocational vehicle has such extensive stationary accessory demands that an auxiliary power

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
source is impractical or that an over-ride condition would be experienced frequently, we would
not consider AES to be feasible. In the Phase 2 certification process, engine suppliers will attest
whether this feature is present and tamper-proof, and certifying entities will be able to enter Yes
or No as a GEM input for the applicable field.M As with neutral idle described above, the
effectiveness of AES will be calculated in GEM using data obtained through engine testing. The
appropriate data points over the parked idle cycle will be used for calculating the fueling. Based
on GEM simulations using the final vocational vehicle test cycles, the agencies project AES to
provide fuel efficiency improvements ranging from less than one to seven percent for diesel
vehicles, and from three to eight percent for gasoline vehicles, depending on the regulatory
subcategory. Other overrides are listed in the regulations at 40 CFR 1037.660.
While the primary program does not simulate vocational vehicles over a test cycle that
includes PTO operation, the agencies will continue, with revisions, the hybrid-PTO test option
that was in Phase 1. See 40 CFR 1037.540 and 76 FR 57247. Recall that we will regulate
vocational vehicles at the incomplete stage when a chassis manufacturer may not know at the
time of certification whether a PTO will be installed or how the vehicle will be used. Although
chassis manufacturers will certainly know whether a vehicle's transmission is PTO-enabled, that
is very different from knowing whether a PTO will actually be installed and how it will be used.
Chassis manufacturers may rarely know whether the PTO-enabled vehicle will use this capability
to maneuver a lift gate on a delivery vehicle, to operate a utility boom, or merely as a reserve
item to add value in the secondary market. In cases where a manufacturer can certify that a PTO
with an idle-reduction technology will be installed either by the chassis manufacturer or by a
second stage manufacturer, the hybrid-PTO test cycle may be utilized by the certifying
manufacturer to measure an improvement factor over the GEM duty cycle that would otherwise
apply to that vehicle. In addition, the delegated assembly provisions would apply. See Preamble
Section I.F.2 for a description of the delegated assembly provisions. See RIA Chapter 3.7.4 for a
discussion of the revisions to the hybrid PTO test cycle. In cases where a chassis manufacturer
does not know whether a powertrain that is PTO-enabled will actually have a PTO-using tool
installed, and whether there will be an energy storage system installed to save fuel during PTO
operation, then the agencies do not see a way for the Phase 2 program to recognize hybrid PTO
technology.
Our estimates are that applying neutral idle to a vocational vehicle with an automatic
transmission would cost $118 in MY 2021, decreasing to $114 in MT 2027, as shown in RIA
2.11.6.5. These costs are increased from proposal, based on comments from Allison indicating
hardware may be needed, such as a sensor to detect brake position or road grade. Our estimates
are that applying AES to a vocational vehicle would cost $30 in MY 2021, decreasing to $25 in
MT 2027, as shown in RIA 2.11.6.7. This cost does not include the cost of an auxiliary power
source while the engine is off.
Based on GEM simulations using the final vocational vehicle test cycles, the agencies
project stop-start to provide fuel efficiency improvements ranging from less than one to 14
percent for diesel vehicles, and from one to ten percent for gasoline vehicles, depending on the
regulatory subcategory. Our estimates are that the cost of applying stop-start to a vocational
vehicle will vary by vehicle weight class, because varying amounts of engine and vehicle
M We will consider non-tamper-proof AES as off-cycle technologies for a lesser credit.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
upgrades will be needed. For LHD vocational vehicles, we estimate the total cost would range
from $871 in MY 2021 to $722 in MY 2027. For MHD vocational vehicles, we estimate the
total cost would range from $917 in MY 2021 to $760 in MY 2027. For HHD vocational
vehicles, we estimate the total cost would range from $1,683 in MY 2021 to $1,395 in MY 2027.
These costs, presented in RIA Chapter 2.11.6.6, are derived from costs reported by Tetra Tech
for stop-start, plus costs for electrified accessories derived from values used in the light-duty
GHG program, and scaled up for heavier vehicles.
With either a stop-start engine feature or with a neutral idle transmission calibration, less
fuel is burned at idle. Furthermore, it is expected that SCR catalyst function could be better
managed when an engine shuts off than when it idles. SCR systems are well insulated and can
maintain temperature when an engine is shut off, whereas idling causes relatively cool air to flow
through a catalyst. Therefore, the agencies have reason to believe there may be a NOx co-
benefit to stop-start idle reduction technologies, and possibly also to neutral idle. This would be
true if the NOx reductions from reduced fuel consumption and retained aftertreatment
temperature were greater than any excess NOx emissions due to engine re-starts.
2.9.3.5 Weight Reduction
The agencies are predicating the final vocational vehicle standards in part on use of
material substitution for weight reduction. The method of recognizing this technology is similar
to the method used for tractors. The agencies have created a menu of vocational chassis
components with fixed reductions in pounds that may be entered in GEM when substituting a
component made of a more lightweight material than the base component made of mild steel.
According to the 2009 TIAX report, there are freight-efficiency benefits to reducing weight on
vocational vehicles that carry heavy cargo, and tax savings potentially available to vocational
vehicles that remain below excise tax weight thresholds. This report also estimates that the cost
effectiveness of weight reduction over urban drive cycles is potentially greater than the cost
effectiveness of weight reduction for long haul tractors and trailers. We are adopting as
proposed a GEM allocation of half the weight reduction to payload and half to reduced chassis
weight. We did not receive comment suggesting a different weight allocation. The menu of
components available for a vocational vehicle weight credit in GEM is presented in Table 2-70
and can be found in the regulations at 40 CFR 1037.520. It includes fewer options than
proposed, due to comments from Allison that aluminum transmission cases and clutch housings
are standard for automatic transmissions. The agencies believe there are a number of other
feasible material substitution choices at the chassis level, which could add up to weight savings
of hundreds of pounds. The stringency of the final vocational vehicle standards for custom
chassis transit buses and vehicles in the primary program is based in part on use of aluminum
wheels in 10 positions on 3-axle vocational vehicles (250 lbs) and in 6 wheel positions on 2-axle
vocational vehicles (150 lbs). This is a change from proposal, where we believed application of
lightweight components would be adopted more narrowly. Our projected adoption rate is revised
upward based on the determination that the technology package is smaller (fewer pounds
removed than at proposal) and that aluminum wheels are widely feasible. Based on the default
payloads in GEM, and depending on the vocational vehicle subcategory, the agencies estimate a
reduction of 250 lbs would offer a fuel efficiency improvement of up to one percent for HHD
vehicles, and a reduction of 150 pounds would offer a fuel efficiency improvement up to 0.8
percent for MHD vehicles, and up to 1.5 percent for LHD vehicles, as shown in Table 2-69. The

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
agencies estimate the total cost to apply aluminum wheels to LHD and MHD vocational vehicles
(about 150 pounds) to be $693 in MY 2021 and $587 in MY 2027, as described in RIA
2.11.10.3. We estimate the total cost to apply aluminum wheels to 3-axle vocational vehicles
(about 250 pounds) to be $2495 in MY 2021 and $2204 in MY 2027, as described in RIA
2.11.10.3. This is in the range of $3 to $10 per pound, as reported by TIAX 2009.163
Table 2-69 Estimated Effectiveness of Vocational Weight Reduction

HHD
MHD
LHD
Weight Reduction
250
0
150
0
150
0
Static Test Weight (kg)
18,994
19,051
11,374
11,408
7,223
7,257
Dynamic Test Weight (kg)
19,561
19,618
11,714
11,748
7,563
7,597
Payload (ton)
7.5625
7.5
5.6375
5.6
2.8875
2.85
Effectiveness over Transient
1.0%

0.8%

1.5%

Effectiveness over 55 mph
0.9%
0.7%
1.4%
Effectiveness over 65 mph
0.9%
0.7%
1.4%
Urban Cycle Effectiveness
1.0%
0.8%
1.5%
Multi-Purpose Cycle
Effectiveness
0.9%
0.8%
1.4%
Regional Cycle Effectiveness
0.9%
0.7%
1.4%

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-70 Vocational Weight Reduction Technologies
COMPONENT
MATERIAL
VOCATIONAL VEHICLE CLASS
Class 2b-5
Class 6-7
Class 8
Axle Hubs - Non-Drive
Aluminum
40
40
Axle Hubs - Non-Drive
High Strength Steel
5
5
Axle - Non-Drive
Aluminum
60
60
Axle - Non-Drive
High Strength Steel
15
15
Brake Drums - Non-Drive
Aluminum
60
60
Brake Drums - Non-Drive
High Strength Steel
42
42
Axle Hubs - Drive
Aluminum
40
80
Axle Hubs - Drive
High Strength Steel
10
20
Brake Drums - Drive
Aluminum
70
140
Brake Drums - Drive
High Strength Steel
37
74
Suspension Brackets, Hangers
Aluminum
67
100
Suspension Brackets, Hangers
High Strength Steel
20
30
Crossmember - Cab
Aluminum
10
15
15
Crossmember - Cab
High Strength Steel
2
5
5
Crossmember - Non-Suspension
Aluminum
15
15
15
Crossmember - Non-Suspension
High Strength Steel
5
5
5
Crossmember -Suspension
Aluminum
15
25
25
Crossmember -Suspension
High Strength Steel
6
6
6
Driveshaft
Aluminum
12
40
50
Driveshaft
High Strength Steel
5
10
12
Frame Rails
Aluminum
120
300
440
Frame Rails
High Strength Steel
40
40
87
Wheels - Dual
Aluminum
150
150
250
Wheels - Dual
High Strength Steel
48
48
80
Wheels - Wide Base Single3
Aluminum
294
294
588
Wheels - Wide Base Single3
High Strength Steel
168
168
336
Permanent 6x2 Axle Configuration
Multi
N/A
N/A
300
Note:
" Based on values from Table 6 of 40 CFR 1027.520 and use of four wide base singles on Class 8 vocational
vehicles and two on vehicles with one drive axle.
2.9.3.6 Electrified Accessories
Reducing the mechanical and electrical loads of accessories reduces the power
requirement of the engine and in turn reduces the fuel consumption and CO2 emissions.
Modeling in GEM, as shown in Table 2-71, demonstrates there is a measurable effect of
reducing 1 kW of accessory load for each vocational subcategory.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-71 Effect of Accessory Load Reduction on Vocational CO2 Emissions
VOCATIONAL
SUBCATEGORY
DIESEL (CI) PERCENT C02 PER
KW
GASOLINE (SI) PERCENT
C02 PER KW
HHDR
0.95%
-
HHDM
1.62%
-
HHDU
1.82%
-
MHDR
1.39%
1.28%
MHDM
2.62%
2.14%
MHDU
3.15%
2.48%
LHDR
2.00%
1.87%
LHDM
3.38%
2.91%
LHDU
3.95%
3.44%
Optimization and improved pressure regulation may significantly reduce the parasitic
load of the water, air and fuel pumps. Electrification may result in a reduction in power demand,
because electrically-powered accessories (such as the air compressor or power steering) operate
only when needed if they are electrically powered, but they impose a parasitic demand all the
time if they are engine-driven. In other cases, such as cooling fans or an engine's water pump,
electric power allows the accessory to run at speeds independent of engine speed, which can
reduce power consumption.
Some vocational vehicle applications have much higher accessory loads than is assumed
in the default GEM configurations. In the real world, there may be some vehicles for which
there is a much larger potential improvement available than those listed above, as well as some
for which electrification is not cost-effective. To date, accessory electrification has been
associated only with hybrids, although CalStart commented they are optimistic that accessory
electrification will become more widespread among conventional vehicles in the time frame of
Phase 2.
Electric power steering (EPS) or Electrohydraulic power steering (EHPS) provides a
potential reduction in CO2 emissions and fuel consumption over hydraulic power steering
because of reduced overall accessory loads. This eliminates the parasitic losses associated with
belt-driven power steering pumps which consistently draw load from the engine to pump
hydraulic fluid through the steering actuation systems even when the wheels are not being
turned. EPS is an enabler for all vehicle hybridization technologies since it provides power
steering when the engine is off. EPS is feasible for most vehicles with a standard 12V system.
Some heavier vehicles may require a higher voltage system which may add cost and complexity.
Although we did not propose to allow pre-defined credit for electrified accessories as was
proposed for tractors, we received comment requesting that this be allowed for vocational
vehicles. As discussed in 2.9.3.1 above, the agencies are projecting that some electrified
accessories will be necessary as part of the development of stop-start idle reduction systems for
vocational vehicles. The technology package for vocational stop-start includes costs for high-
efficiency alternator, electric water pump, electric cooling fan, and electric oil pump. However,
because the GEM algorithm for determining the fuel benefit of stop-start does not account for

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
any e-accessories, vehicles certified with stop-start are also eligible to be certified using an
improvement value in the e-accessories column.
Daimler, ICCT, Bendix, Gentherm, Navistar, Odyne, and CARB asked the agencies to
consider electric cooling fans, variable speed water pumps, clutched air compressors, electric air
compressors, electric power steering, electric alternators, and electric AJC compressors. ICCT
cautioned that certain accessories would be recognized over an engine test and credit should not
be duplicated at the vehicle level. Bosch suggested that high-efficiency alternators be
considered, and suggested use of a standard component-level test for alternators to determine
their efficiency, and establishment of a minimum efficiency level that must be attained.
Although there are industry-accepted test procedures for measuring the performance of
alternators, we do not have sufficient information about the baseline level performance of
alternators to define an improved level that would qualify for a benefit at certification. We are
not able to set a fixed improvement for electric cooling fans or clutched accessories due to
similar challenges related to baselines and defining the qualifying technology. In consideration
of ICCT's comment, we are not including water pumps and oil pumps among the components
eligible for a fixed improvement because we believe that our engine test procedure will
recognize improvements that would be seen in the real world from electrifying these parts. Thus,
we believe it is appropriate to offer fixed technology improvements for use of electric power
steering and an electric AJC compressor, as inputs to GEM.
The agencies have combined the GEM results shown in Table 2-71 with information
from comments provided by ICCT, the TIAX 2009 technology report, CARB's Driveline
Optimization report, the 2010 NAS report, and a 2014 article published in IET Electrical
Systems in Transportation to assign fixed improvement values for the defined technologies
shown in Table 2-72.164 These values are consistent with the TIAX study that used 2 to 4
percent fuel consumption improvement for accessory electrification, with the understanding that
electrification of accessories will have more effect in short haul/urban applications and less
benefit in line-haul applications.165
Table 2-72 Effectiveness of Vocational E-Accessories
TECHNOLOGY
EFFECTIVENESS
SUBCATEGORIES
Electric A/C Compressor
0.5%
HHD
1.0%
MHD & LHD
Electric Power Steering
0.5%
Regional
1.0%
Multipurpose & Urban
The improvement value for electric AJC compressors was estimated using a value of 4.7
kW demand from Table 5-11 of the 2010 NAS report, along with an assumption that it runs on
average 40 percent of the time, and that electrification reduces the total load to the engine by 40
percent. Combining these values with the GEM-derived values of percent CO2 per kW reduced
from Table 2-71, the improvement is estimated to be in the range of 0.5 to three percent
depending on the subcategory. The improvement value for electric power steering was estimated
using an average value of 2 kW demand from Table 5-11 of the 2010 NAS report, along with an
assumption that it runs on average 60 percent of the time, and that electrification reduces the
total load to the engine by 40 percent. Combining these values with the GEM-derived values of

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
percent CO2 per kW reduced from Table 2-71, the improvement is estimated to be in the range
of 0.5 to 1.5 percent depending on the subcategory. We have selected conservative values from
these results as fixed technology improvements.
The agencies estimate the total cost to electrify accessories as described above on a LHD
vocational vehicle to be $425 in MY 2021 and $369 in MY 2027. Scaling up, the costs for a
MHD vocational vehicle are estimated at $801 in MY 2021 and $697 in MY 2027, and the costs
for a HHD vocational vehicle are estimated at $1,603 in MY 2021 and $1,393 in MY 2027, as
described in RIA 2.11.10.2.
Manufacturers wishing to obtain credit for technologies that are more effective than we
have projected, or technologies beyond the scope of this defined technology improvement, may
apply for off-cycle credits.
2.9.3.7 Tire Pressure Systems
2.9.3.7.1 TPMS
The agencies did not propose to base the vocational vehicle standards on the performance
of tire pressure monitoring systems (TPMS). However, we received comment that we should
consider this technology. See discussion in Preamble Section III.D. 1 .b. In addition to comments
related to tractors and trailers, RMA commented that TPMS can also apply to the class 2b - 6
vehicles, and if the agencies add TPMS to the list of recognized technologies, that this choice
should also be made available to class 2b-6 vehicles. Bendix commented that TPMS is a proven
product, readily available from a number of truck, bus, and motorcoach OEMs. Autocar
commented that TPMS is useful for refuse truck applications. Tirestamp said that TPMS is ideal
for trucks and buses that are unable to apply ATIS due to difficulties plumbing air lines
externally of the axles. The agencies find these comments to be persuasive. As a result, we are
finalizing vocational vehicle standards that are predicated on the performance of TPMS in all
subcategories, including all custom chassis except emergency vehicles and concrete mixers.
Available information indicates that it is feasible to utilize TPMS on all vocational vehicles,
though systems for heavy vehicles in duty cycles where the air in the tires becomes very hot
must be ruggedized so that the sensors are protected from this heat. Such devices are
commercially available, though they cost more. To account for this in our analysis, we have
projected a lower adoption rate for TPMS in Urban vehicles than for Regional or Multipurpose
vehicles, rather than by increasing the cost and applying an equal adoption rate. We are
assigning a fixed improvement value in GEM for use of this technology in vocational vehicles of
one percent for Regional vehicles including motor coaches and RV's (the same as for tractors
and trailers) and 0.9 percent for Multipurpose, Urban, and other custom chassis vocational
vehicles, recognizing that the higher amount of idle is likely to reduce the effectiveness for these
vehicles. These values will be specified as GEM inputs in the column designated for tire
pressure systems. For HHD vocational vehicles (with 3 axles), the agencies estimate the cost of
TPMS at $583 in MY 2021 and $507 in MY 2027, as described in RIA 2.11.8.9. For LHD and
MHD vocational vehicles, we scaled down the cost of this technology to reflect the presence of a
single rear axle. The agencies estimate the total cost of TPMS on a LHD or MHD vocational
vehicle (with 2 axles) at $307 in MY 2021 and $267 in MY 2027.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.9.3.7.1.1 ATIS
The agencies did not propose to base the vocational vehicle standards on the performance
of automatic tire inflation systems (ATIS), otherwise known as central tire inflation (CTI).
However, we did receive comment indicating that it is feasible on some vocational vehicles,
specifically those which could choose to be certified as custom chassis. Air CTI commented that
central tire inflation is not only feasible but enhances safety on vehicles such as dump trucks and
heavy haul vehicles that need higher tire pressures under certain driving conditions, such as
when loaded, but need lower tire pressures when running empty or operating off-road.
Tirestamp commented that ATIS can be plumbed externally for trucks and buses, but such
systems have a propensity for damage and Autocar has provided information about how much
extra weight this plumbing adds to the chassis. ATA commented that some onboard air pressure
systems may not be able to pressurize tires sufficiently for very heavy vehicles. The primary
vocational vehicle standards are not predicated on any adoption of ATIS because the agencies do
not have sufficient information about which chassis will have an onboard air supply for purposes
of an air suspension or air brakes. ATIS would logically only be adopted for vehicles that
already need an onboard air supply for other reasons. Comments received for custom chassis
were supportive of standards predicated on ATIS for buses with air suspensions. These
comments are again persuasive. As a result, we are basing the optional standards for refuse
trucks, school buses, coach buses, and transit buses in part on the adoption of ATIS. Although
many motor homes have onboard air supply for other reasons making ATIS technically feasible,
it is sufficiently costly that it is not practically feasible. Furthermore, for the same reasons stated
above about the disadvantages of installing external plumbing for ATIS on some trucks and
buses, we have determined it is not feasible for emergency vehicles or concrete mixers.
Nonetheless, we are allowing any vocational vehicle to obtain credit for the performance of
ATIS through a GEM input with a fixed improvement value in GEM for use of this technology
in vocational vehicles of 1.2 percent for Regional vehicles including motor coaches and RV's
(the same as for tractors and trailers) and 1.1 percent for Multipurpose, Urban, and other custom
chassis vocational vehicles, recognizing that the higher amount of idle is likely to reduce the
effectiveness for these vehicles. These values will be specified as GEM inputs in the column
designated for tire pressure systems. See discussion in Preamble Section III.D. 1 .b for our
reasoning behind this effectiveness value. Because ATIS is not projected as a technology in the
basis for the mandatory vocational vehicle standards, we have not estimated detailed costs for
applying this technology on these vehicles. Even so, in RIA 2.11.8.8 (see Table 2-130), the
agencies estimate the cost of ATIS on 3-axle tractors to be $916 in MY 2021 and $796 in
MY2027. We would expect the cost to apply ATIS on a 3-axle vocational vehicle to be
comparable to these costs. Table 2-133 in RIA 2.11.8.8 presents costs the agencies have
estimated to apply ATIS on short van trailers; $481 in MY 2021 and $418 in MY 2027. We
would expect the cost to apply ATIS on a 2-axle vocational vehicle to be comparable to these
costs.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.9.3.8 HFC Leakage
Emissions due to direct refrigerant leakage are significant in all vehicle types. Since the
proposal, EPA has learned that the capacities of vocational vehicle air conditioning systems
range from those that are similar to those of other HD vehicles to some that are much larger.
Even considering these differences, we believe it is appropriate to apply a similar leakage
standard as was applied in the HD Phase 1 program for tractors and HD pickup trucks and vans.
EPA is adopting a 1.50 percent refrigerant leakage per year standard for each air conditioning
system with a refrigerant capacity greater than 733 grams, to assure that high-quality, low-
leakage components are used in the design of these systems. Since refrigerant leakage past the
compressor shaft seal is the dominant source of leakage in belt-driven air conditioning systems,
the agency recognizes that this 1.50 percent leakage standard is not feasible for systems with a
refrigerant capacity of 733 grams or lower, as the minimum feasible leakage rate does not
continue to drop as the capacity or size of the air conditioning system is reduced. The fixed
leakage from the compressor seal and other system devices results in a minimum feasible yearly
leakage rate. EPA does not believe that leakage reducing technologies will be available in MY
2021 to enable lower capacity systems to meet the percent per year standard, so we are adopting
a maximum gram per year leakage standard of 11.0 grams per year for vocational vehicle air
conditioning systems with a refrigerant capacity of 733 grams or lower, as was adopted in the
HD Phase 1 program for tractors and HD pickup trucks and vans.
The standard is derived from the vehicles with the largest system refrigerant capacity
based on the Minnesota GHG Reporting database.166 These are the same data on which the HD
Phase 1 HFC leakage standard was based.167
By requiring that all vocational vehicles achieve the leakage level of 1.50 percent per
year, roughly half of the vehicles in the 2010 data sample would need to reduce their leakage
rates, and an emissions reduction roughly comparable to that necessary to generate direct
emission credits under the light-duty vehicle program would result. See 75 FR at 25426-247.
However, no credits or trading flexibilities are available under this standard for heavy-duty
vocational vehicles. We believe that a yearly system leakage approach assures that high-quality,
low-leakage, components are used in each A/C system design, and we expect that manufacturers
will reduce A/C leakage emissions by utilizing improved, leak-tight components. Some of the
improved components available to manufacturers are low-permeation flexible hoses, multiple o-
ring or seal washer connections, and multiple-lip compressor shaft seals. The availability of low
leakage components in the market is being driven by the air conditioning credit program in the
light-duty GHG rulemaking (which applies to 2012 model year and later vehicles). EPA
believes that reducing A/C system leakage is both highly cost-effective and technologically
feasible. The cooperative industry and government Improved Mobile Air Conditioning (IMAC)
program has demonstrated that new-vehicle leakage emissions can be reduced by 50 percent by
reducing the number and improving the quality of the components, fittings, seals, and hoses of
the A/C system.168 All of these technologies are already in commercial use and exist on some of
today's A/C systems in other heavy-duty vehicles.
EPA is adopting the same compliance method for control of leakage from A/C systems in
vocational vehicles as was adopted for the HD Phase 1 HFC leakage standard. Under this
approach, manufacturers will choose from a menu of A/C equipment and components used in

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
their vehicles in order to establish leakage scores, which characterizes their AJC system leakage
performance and calculates the percent leakage per year as this score divided by the system
refrigerant capacity. The agencies estimate the total cost to apply low leakage AJC components
to a vocational vehicle to be $22 in MY 2021 and $20 in MY 2027, as described in RIA 2.11.4.1.
Consistent with the Light-Duty Vehicle Greenhouse Gas Emissions rulemaking, the
components of vocational vehicle AJC systems are being compared to a set of leakage reduction
technologies that is based closely on that being developed through IMAC and the Society of
Automotive Engineers (as SAE Surface Vehicle Standard J2727, August 2008 version).169 See
generally 75 FR at 25426. The SAE J2727 approach was developed from laboratory testing of a
variety of AJC related components, and EPA believes that the J2727 leakage scoring system
generally represents a reasonable correlation with average real-world leakage in new vehicles.
Like the IMAC approach, our approach associates each component with a specific leakage rate
in grams per year identical to the values in J2727 and then sums together the component leakage
values to develop the total AJC system leakage. As is currently done for other HD vehicles, for
vocational vehicles, the total AJC leakage score will then be divided by the total refrigerant
system capacity to develop a percent leakage per year value.
2.9.4 Other Vocational Vehicle Technologies the Agencies Considered
2.9.4.1 Vocational Aerodynamics
The agencies did not propose to include aerodynamic improvements as a basis for the
Phase 2 vocational vehicle standards. However, we did request comment on an option to allow
credits for use of aerodynamic devices such as fairings on a very limited basis. We received
public comments from AAPC in support of offering this as an optional credit, with a suggestion
to allow this option for a wide range of vehicle sizes, and suggesting that the grams per ton-mile
benefit could be scaled down for larger vehicles. CARB commented in support of a Phase 2
program that would include use of aerodynamic improvements as a basis for the stringency,
suggesting that a large fraction of the vocational vehicle fleet could see real world benefits from
use of aerodynamic devices. Because we do not have sufficient fleet information to establish a
projected application rate for this technology, we are not basing any of the final standards for
vocational vehicles on use of aerodynamic improvements. In consideration of comments, we are
adopting provisions for vocational vehicles to optionally receive an improved GEM result by
certifying use of a pre-approved aerodynamic device.
Based on testing supported by CARB, the agencies have developed a list of specific
aerodynamic devices with pre-defined improvement values (in delta CdA units), as well as
criteria regarding which vehicles are eligible to earn credit in this manner. Manufacturers
wishing to receive credit for other aerodynamic technologies or on other vehicle configurations
may apply for credits using the test procedures at 40 CFR 1037.527.
Table 2-73 shows the vocational aerodynamic technologies that we are adopting as pre-
approved, for which the credit listed is available through GEM. In response to comments, we are
allowing a wide range of vehicles to be eligible to use this option. Vocational vehicles in any
weight class over the Regional duty cycle may use this option, subject to restrictions on the size
of the cargo box (see 40 CFR 1037.520). The agencies have not estimated manufacturing costs

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
for these technologies on vocational vehicles. We project that a manufacturer would only apply
these where it was found to be cost-effective for the specific application. For a description of the
costs estimated for applying aerodynamic technologies to tractors, see the RIA at Chapter
2.11.9.1, where the estimated cost for a Bin2 package on a low roof day cab tractor is shown to
be roughly $1,000.
Table 2-73 Pre-approved Vocational Aerodynamic Technologies
VEHICLE
SKIRT
FRONT
FAIRING
(NOSE CONE)
REAR
FAIRING
(TAIL)
BOTH FRONT
FAIRING AND
SKIRT
Total chassis length at least 36 ft
and frontal area at least 9 m2
0.3
0.3

0.5
Total chassis length at least 23 ft
and frontal area at least 8 m2


0.2

A description of the testing that was conducted in support of the assigned GEM
improvements due to these technologies is presented in the draft report from NREL to CARB.170
The degree of change in CdA for each pre-approved device has been set at conservative values
due to the small number of configurations tested and the large uncertainty inherent in those
results. As an example of the degree of uncertainty, the change in CdA on the class 6 box truck
due to applying a chassis skirt was reported by NREL in Table 8 as being approximately -0.6 m2
with a 95 percent confidence interval of plus or minus -0.6 m2 Manufacturers using this credit
provision may enter the pre-defined delta CdA as an input to GEM, and the simulation will
determine the effectiveness over the applicable duty cycle. Using this approach, we do not need
to set a scaled benefit for different sizes of vehicles. When the vehicle weight class and duty
cycle are specified, a default chassis mass and payload are simulated in GEM. When the pre-
defined delta CdA is entered, the simulation returns a resulting improved performance with
respect to the specified chassis configuration. GEM will logically return a smaller improvement
for heavier vehicles.
The final Regional composite duty cycle in GEM for vocational vehicles has a weighted
average speed of 41.9 mph, increased from the average speed at proposal due to a heftier 56
percent composite weighting of the 65 mph drive cycle. The agencies have learned from the
NREL duty cycle analysis that vocational vehicles with operational behavior of a regional nature
accumulate more miles at highway speeds than previously assumed.
Using GEM simulation results, the agencies estimate the fuel efficiency benefit of
improving the CdA of a Class 6 box truck by 11 percent (0.6 m2 delta CdA off of a default of 5.4
m2) at approximately five percent over the Regional composite test cycle. This same delta CdA
simulated in GEM on a class 8 Regional vocational vehicle results in an overall improvement of
less than four percent because the default CdA in GEM for class 8 vocational vehicles is 6.86 m2
so the change in CdA is only nine percent. Although in actual operation the added weight of
aerodynamic fairings may reduce the operational benefits of these technologies when driving at
low speeds, the agencies are not applying any weight penalty as part of the certification process
for vocational aerodynamic devices.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
As described in the NPRM, we are requiring chassis manufacturers employing this option
to provide assurances to the agencies that these devices will be installed as part of the certified
configuration, even if the installation is completed by another entity. We received many
comments on the requirements for secondary manufacturers as they apply for vocational
aerodynamics as well as other technologies that may be specified by a chassis manufacturer but
installed later. See Preamble Section I.F.2 and Section V.D.2 for further discussion of delegated
assembly issues.
2.9.4.2 E-PTO
Although the primary program does not simulate vocational vehicles over a test cycle that
includes PTO operation, the agencies are adopting a revised hybrid-PTO test procedure. See 76
FR 57247 and 40 CFR 1037.540. Recall that we regulate vocational vehicles at the incomplete
stage when a chassis manufacturer may not know at the time of certification whether a PTO will
be installed or how the vehicle will be used. Chassis manufacturers may rarely know whether
the PTO-enabled vehicle will use this capability to maneuver a lift gate on a delivery vehicle, to
operate a utility boom, or merely to keep it as a reserve item to add value in the secondary
market. For these reasons, it would not be fair to require every vocational vehicle to certify to a
standard test procedure with a PTO cycle in it. Thus, we are not basing the final standards on
use of technology that reduces emissions in PTO mode.
There are products available today that can provide auxiliary power, usually electric, to a
vehicle that needs to work in PTO mode for an extended time, to avoid idling the main engine.
There are different designs of electrified PTO systems on the market today. Some designs have
auxiliary power sources, typically batteries, with sufficient energy storage to power an onboard
tool or device for a short period of time, and are intended to be recharged during the workday by
operating the main engine, either while driving between work sites, or by idling the engine until
a sufficient state of charge is reached that the engine may shut off. Other designs have sufficient
energy storage to power an onboard tool or device for many hours, and are intended to be
recharged as a plug-in hybrid at a home garage. In cases where a manufacturer can certify that a
PTO with an idle-reduction technology will be installed either by the chassis manufacturer or by
a second stage manufacturer, the hybrid-PTO test cycle may be utilized by the certifying
manufacturer to measure an improvement factor over the GEM duty cycle that otherwise applies
to that vehicle. In addition, the delegated assembly provisions will apply (see Section I.F.2).
See RIA Chapter 3.7.4 for a discussion of the revisions to the PTO test cycle.
The agencies will continue the hybrid-PTO test option that was available in Phase 1, with
a few revisions. See the regulations at 40 CFR 1037.540. The calculations recognize fuel
savings over a portion of the test that is determined to be charge-sustaining as well as a portion
that is determined to be charge-depleting for systems that are designed to power a work truck
during the day and return to the garage where recharging from an external source occurs during
off-hours. The agencies requested comment on this idea, and received comment from Odyne
relating to the population and energy storage capacity of plug-in e-PTO systems, for which a
charge-depleting test cycle may be more appropriate. We also partnered with DOE-NREL to
characterize the PTO operation of many vocational vehicles. NREL has characterized the PTO
operation using telematics data from Odyne on over 80 utility trucks with over 1,500 total
operating days, plus telematics data on ten utility trucks from PG&E with hundreds of operating

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
days. Our final regulations include a utility factor table based on these data for use in
determining the effectiveness of a hybrid PTO system. A description of the analysis underlying
the development of this utility factor curve is available in the docket.171 Manufacturers wishing
to conduct testing as specified may apply for off-cycle credits derived from e-PTO or hybrid
PTO technologies.
2.9.4.3 Electric Vehicles
Some heavy-duty vehicles can be powered exclusively by electric motors. Electric
motors are efficient and able to produce high torque, giving e-trucks strong driving
characteristics, particularly in stop-and-go or urban driving situations, and are well-suited for
moving heavy loads. Electric motors also offer the ability to operate with very low noise, an
advantage in certain applications. Currently, e-trucks have some disadvantages over
conventional vehicles, primarily in up-front cost, weight and range. Components are relatively
expensive, and storing electricity using currently available technology is expensive, bulky, and
heavy. However commenters provided information on total cost of ownership for electric trucks,
and some applications may see attractive long term cost scenarios for electric trucks or buses,
considering maintenance savings.
The West Coast Collaborative, a public-private partnership, has estimated the incremental
costs for electric Class 3-6 trucks in the Los Angeles, CA, area.172 Compared to a conventional
diesel, the WCC estimates a battery-electric vehicle system would cost between $70,000 and
$90,000 more than a conventional diesel system. The CalHEAT Technology Roadmap includes
an estimate that the incremental cost for a fully-electric medium- or heavy- duty vehicle would
be between $50,000 and $100,000. In the Draft RIA Chapter 2.12.7.6, the agencies estimated the
cost of a full electric LHD or MHD vocational vehicle at $55,216 in MY 2021 and $52,128 in
MY 2024. The CalHEAT roadmap report also presents several actions that must be taken by
manufacturers and others, before heavy-duty e-trucks can reach what they call Stage 3
Deployment.173
Early adopters of electric drivetrain technology are medium-heavy-duty vocational
vehicles that are not weight-limited and have drive cycles where they don't need to go far from a
central garage. According to CALSTART's report to the NAFA 2014 Institute and Expo, there
is an emerging market of MHD all-electric vocational vehicles, including models from Smith,
EVI, Boulder, AMP, and others. It is a significant stepping stone that we are seeing these
emerging markets, where prototype and demonstration vehicles can be tested and observed in
real world conditions. CalHEAT has published results of a comprehensive performance
evaluation of three battery electric truck models using information and data from in-use data
collection, on road testing and chassis dynamometer testing.174
Given the high costs and the developing nature of this technology, the agencies do not
project fully electric vocational vehicles to be widely commercially available in the time frame
of the final Phase 2 rules. For this reason, the agencies have not based the Phase 2 standards on
adoption of full-electric vocational vehicles. EEI provided information on the total cost of
ownership for electric trucks, where under certain conditions some vehicle applications may see
attractive long term cost scenarios for electric trucks or buses, when considering maintenance
savings. To the extent this technology is able to be brought to market in the time frame of the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Phase 2 program, there is currently a certification path for these chassis from Phase 1, as
described in the Preamble Section V and in the regulations at 40 CFR 1037.150 and 49 CFR
535.8.
2.9.5 Derivation of the Vocational Vehicle Technology Packages
The final standards for vocational vehicles are predicated on the same suite of
technologies in all implementation years of the Phase 2 program. The change in stringency
between those years is a result of different adoption rates of those technologies. Package costs
for each model year are presented following each respective adoption rate discussion.
2.9.5.1 Projected Technology Adoption Rates for Vocational Vehicles
The agencies describe below the extent to which technologies may be adopted by
manufacturers to meet each set of vocational vehicle standards.
2.9.5.1.1 Transmissions
Because we expect that transmission suppliers will be able to conduct a modest amount
of testing that can be valid for a large sales volume of transmissions, the agencies project an
adoption rate of 50 percent in MY 2021, 60 percent in MY 2024, and nearly 70 percent in MY
2027 of transmissions with improved gear efficiencies, with inputs over-riding the GEM defaults
obtained over the separate transmission efficiency test. In response to comments regarding the
diversity of drivelines and the narrow range of products for which powertrain testing is likely to
be conducted, we are projecting an adoption rate of 10 percent in MY 2021, 20 percent in MY
2024, and nearly 30 percent in MY 2027 of advanced shift strategies, with demonstration of
improvements recognized over the separate powertrain test. With additional time and research,
we expect that the adoption of this strategy for improving fuel efficiency will grow.
We are predicating the Phase 2 standards on zero adoption of added gears in the HHD
Regional subcategory, because it is modeled with a 10-speed transmission, and vehicles already
using that number of gears are not expected to see any real world improvement by increasing the
number of available gears. For the Multipurpose and Urban HHD subcategories, the MY 2021
projected adoption of adding gears is 5 percent, increasing to 10 percent for MY 2024 and MY
2027. We are projecting 10 percent of adding two gears in each of the other six subcategories
for MY 2021, increasing to 20 percent for MY 2024 and MY2027. Commenters supported the
inclusion of this technology as part of the basis for the standards. Allison commented that they
have configured an 8-speed vocational transmission. Eaton's new MHD dual clutch transmission
has seven forward gears. There is also a likelihood that suppliers of 8-speed transmissions for
HD pickups and vans may sell some into the LHD vocational vehicle market.
We are also predicating the optional custom chassis standards for school and coach buses
in part on adoption of transmissions with additional gears. In MY 2021, this adoption rate is five
percent, increasing to 10 percent in MY 2024 and 15 percent in MY 2027. Manufacturers who
certify these vehicles to the primary standards will use GEM to model the actual gears and gear
ratios. Manufacturers opting into the custom chassis program will not have this flexibility. The
agencies have estimated the cycle-average benefit of adding an extra gear for school buses

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
(modeled as MHD Urban vehicles) at 0.9 percent and coach buses (with 6 gears in the baseline)
at 1.7 percent, therefore manufacturers using the custom chassis regulatory subcategory
identifiers for these vehicles will be permitted to enter these pre-defined improvement values at
the time of certification.
Based on comment regarding our regulatory baselines, both the HHD Regional and HHD
Multipurpose subcategories now have manual transmissions in the baseline configuration. For
these vehicles, the agencies project upgrades to automated transmissions such as either AMT,
DCT, or automatic, at an adoption rate of 30 percent in MY 2021, 60 percent in MY 2024, and
90 percent in MY 2027 for Regional vehicles. For Multipurpose, beginning with 20 percent
manuals in the baseline, the adoption rate of automated transmissions is five percent in MY 2021
and 20 percent in MY 2024. Consistent with our projections of technology adoption, the
regulations require that any vocational vehicles with manual transmissions must be certified as
Regional in MY 2024 and beyond. This progression of transmission automation is consistent
with the agencies' projection of 10 percent manuals and 90 percent automated transmissions in
the day cab tractor subcategories in MY 2027. See Table III-13 of the Preamble. HHD
vocational vehicles in regional service have many things in common with day cab tractors,
including the same assumed engine size and typical transmission type, and a similar duty cycle.
Thus, it is reasonable for the agencies to make similar projections about the fraction of
automated vs manual transmissions adopted over the next decade among these sectors.
In the seven subcategories (i.e. all of the remaining subcategories) in which automatic
transmissions are the base technology, the agencies project that ten percent of the HHD vehicles
will apply an aggressive torque converter lockup strategy in MY 2021, and 30 percent in the
LHD and MHD subcategories. These adoption rates are projected to increase to 20 percent for
HHD and 40 percent for LHD and MHD in MY 2024. We project adoption of aggressive torque
converter lockup for HHD automatics of 30 percent in MY 2027, and 50 percent for LHD and
MHD. We project these adoption rates to be greater than that of the fully integrated shift strategy
and less than that of the transmission gear efficiency technologies because this is less complex to
apply and may be entered as a GEM input rather than requiring separate test procedures.
In setting the standard stringency, we have projected that non-integrated (bolt-on) mild
hybrids will not have the function to turn off the engine at stop, while the integrated mild hybrids
will have this function. The agencies have estimated the effectiveness of non-integrated mild
hybrids for vehicles certified in the Urban subcategories will achieve as much as 12 percent
improvement, and integrated systems that turn off at stop will see up to 25 percent improvement
in the Urban subcategories. We have also projected zero hybrid adoption rate (mild or
otherwise) by vehicles in the Regional subcategories, expecting that the benefit of hybrids for
those vehicles will be too low to merit use of that type of technology.
There is no fixed hybrid value assigned in GEM. Consequently, any vehicles utilizing
hybrid technology will determine the actual improvement by conducting powertrain testing.
By the full implementation year of MY 2027, the agencies are projecting an overall
vocational vehicle adoption rate of 12 percent mild hybrids, which we estimate will be 14
percent of vehicles certified in the Multi-Purpose and Urban subcategories (six percent integrated
and eight percent non-integrated). We are projecting a low adoption rate in the early years of the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Phase 2 program, zero integrated hybrid systems and two percent of the bolt-on systems in these
subcategories in MY 2021, and three percent integrated mild hybrids in MY 2024 for vehicles
certified in the Multi-Purpose and Urban subcategories, plus 5 percent non-integrated mild
hybrids in MY 2024. Based on our assumptions about the populations of vehicles in different
subcategories, these hybrid adoption rates are about two percent overall in MY 2021 and six
percent overall in MY 2024. With the revised projection of lower cost mild hybrids instead of
strong hybrids and more robust assessment of effectiveness than at proposal, we are confident
that we can project a slightly higher overall adoption rate than we had at proposal.
Navistar commented with concerns that the agencies may be double counting some of the
improvements of deep integration. For example, the addition of a gear to a transmission may
reduce the added benefit of deep integration, as the transmission may already achieve a more
optimal operation state more often due to the greater number of gears. The agencies have been
careful to project adoption rates and effectiveness of transmission technologies in a way that that
avoids over-estimating the achievable reductions. For example, as we developed the packages,
we reduced the adoption rate of advanced shift strategy by the adoption rate of integrated
hybrids, and we reduced the adoption rate of transmission gear efficiency by the amount of non-
integrated hybrids. This means that in the HHD Multipurpose category in MY 2027, the sum of
adoption rates of hybrids, advanced shift strategy, and transmission gear efficiency is 100
percent. Further, instead of summing the combined efficiencies, we combine multiplicatively as
described in Equation 2-2, below. Transmission improvements are central to the Phase 2
vocational vehicle program, second only to idle reduction. We are projecting that many vehicles
will apply more than one technology that improves vehicle performance with respect to the
transmission, which necessarily means that the adoption rate of transmission technologies in
some subcategories sums to greater than 100 percent. For example, with a 50 percent adoption of
torque converter lockup and a 70 percent adoption of high efficiency gearbox for Regional
vehicles in MY 2027, some vehicles may need to - and could reasonably - apply both. However,
we believe we have fairly accounted for dis-synergies of effectiveness where technologies are
applied to a similar vehicle system.
Custom chassis manufacturers have provided compelling comment that the absence of
recognition in the certification process of improved transmission technology will not deter them
from its adoption. Therefore, although some types of improved transmissions are feasible for
some custom chassis, the fact that these vehicles are typically assembled from off-the-shelf parts
in low production volumes makes them much less likely to have access to the most advanced
transmission technologies. Further, for the reasons described above about non-representative
drivelines in the baseline configurations, we believe that allowing these to be certified with a
default driveline is a reasonable program structure. For school buses and others, if a
manufacturer wishes to be recognized beyond the levels described for adopting improved
transmissions, it may optionally certify to the primary standards.
2.9.5.1.2 Axles
The agencies project that 10 percent of vocational vehicles in all subcategories will adopt
high efficiency axles in MY 2021, 20 percent in MY 2024, and 30 percent in MY 2027, and the
standards are predicated on these penetration rates for high efficiency axles. Fuel efficient
lubricant formulations are widespread across the heavy-duty market, though advanced synthetic

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
formulations are currently less popular.N Axle lubricants with improved viscosity and
efficiency-enhancing performance are projected to be widely adopted by manufacturers in the
time frame of Phase 2. Such formulations are commercially available and the agencies see no
reason why they could not be feasible for most vehicles. Nonetheless, we have refrained from
projecting full adoption of this technology. The agencies do not have specific information
regarding reasons why axle manufacturers may specify a specific type of lubricant over another,
and whether advanced lubricant formulations may not be recommended in all cases. The
agencies received adverse comment on allowing fixed credit for use of high efficiency axles,
whether from lubrication or other mechanical designs. In response, we are adopting a separate
axle efficiency test, which can be used as an input to GEM to over-ride default axle efficiency
values. The low overall adoption rate indicates that we expect axle suppliers to only offer high-
efficiency axles for their most high production volume products, especially those that can serve
both the tractor and vocational market. Therefore, we believe it is unlikely that high-efficiency
axles will be adopted in custom chassis applications. Because we are no longer offering a fixed
improvement for this technology as at proposal, this is only available for vocational vehicles that
are certified to the primary program.
The agencies estimate that 10 percent of HHD Regional vocational vehicles and five
percent of HHD Multipurpose vehicles will adopt part time 6x2 axle technology in MY 2021.
This technology is most likely to be applied to Class 8 vocational vehicles (with 2 rear axles) that
are designed for frequent highway trips. The agencies project a 20 percent for HHD Regional
and 15 percent adoption rate for HHD Multipurpose for part time 6x2 axle technologies in MY
2024. In MY 2027, we project 30 percent adoption of part time 6x2 for HHD Regional and 25
percent for HHD Multipurpose. We are establishing a baseline configuration for coach buses
with a 6x2 axle. If a HHD coach bus is sold with a 6x4 or part time 6x2 axle, the manufacturer
must enter the as-built axle configuration as a GEM input. This is true whether the vehicle is in
the primary program or if it is certified to the custom chassis standard.
2.9.5.1.3 Lower Rolling Resistance Tires
The agencies estimate that the per-vehicle average level of rolling resistance from
vocational vehicle tires could be reduced by up to 13 percent for many vehicles by full
implementation of the Phase 2 program in MY 2027, based on broader adoption of vocational
vehicle tires currently available. We estimate this will yield reductions in fuel use and CO2
emissions of up to 3.3 percent for these vehicles. As proposed, the Phase 2 weighting of steer
tire CRR and drive tire CRR is 0.3 times the steer tire CRR and 0.7 times the drive tire CRR,
representing an average weight distribution of the rear axle(s) carrying 2.3 times the weight of
the front axle. The projected adoption rates of tires with improved CRR for chassis in the
primary program are presented in Table 2-74. The levels lv through 5v noted in the table are
defined in Section V.C. 1 .a.iv of the Preamble. By applying the assumed axle load distribution,
the estimated vehicle CRR improvement projected as part of the MY 2021 standards ranges from
5 to 8 percent, which we project will achieve up to 1.9 percent reduction in fuel use and CO2
emissions, depending on the vehicle subcategory. The agencies estimate the vehicle CRR
N April 2014 meeting with Dana.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
improvement in MY 2024 will range from 5 to 13 percent, yielding reductions in fuel use and
CO2 emissions up to 3.2 percent, depending on the vehicle subcategory.
The agencies believe that these tire packages recognize the variety of tire purposes and
performance levels in the vocational vehicle market, and maintain choices for manufacturers to
use the most efficient tires (i.e. those with lowest rolling resistance) only where it makes sense
given these vehicles' differing purposes and applications.
Table 2-74 Projected LRR Tire Adoption Rates

REGIONAL
MULTIPURPOSE
URBAN

Steer
Drive
Steer
Drive
Steer
Drive
2021 HHD
100% LRR
5v
100% LRR
2v
100% LRR 5v
100% LRR 2v
100%
LRR4v
100% LRR lv
2021 MHD
100% LRR
3v
100% LRR
lv
100% LRR 3v
100% LRR lv
100%
LRR 3v
100% LRR lv
2021 LHD
100% LRR
3v
100% LRR
3v
100% LRR 3v
100% LRR 3v
100%
LRR2v
100% LRR 2v
2024 HHD
100% LRR
5v
100% LRR
3v
100% LRR 5v
100% LRR 2v
100%
LRR4v
100% LRR lv
2024 MHD
100% LRR
5v
100% LRR
3v
100% LRR 3v
50% LRR lv,
50% LRR 2v
100%
LRR 3v
100% LRR lv
2024 LHD
100% LRR
5v
100% LRR
3v
100% LRR 3v
100% LRR 3v
100%
LRR2v
100% LRR 2v
2027 HHD
100% LRR
5v
100% LRR
3v
100% LRR 5v
100% LRR 3v
100%
LRR 5v
100% LRR 2v
2027 MHD
100% LRR
5v
100% LRR
3v
100% LRR 5v
100% LRR 3v
100%
LRR 3v
50% LRR lv,
50% LRR 2v
2027 LHD
100% LRR
5v
100% LRR
3v
100% LRR 5v
100% LRR 3v
100%
LRR 3v
50% LRR 2v,
50% LRR 3v
Table 2-75 presents the projected adoption rates of LRR tires for custom chassis. As
noted in Section V.C.I.a of the Preamble, the adoption rates generally represent improvements in
the range of the 25th to 40th percentile using data from actual vehicles in each application that
were certified in MY 2014. A summary of these data is provided in a memorandum to the
docket.175 An exception to this is emergency vehicles. The final emergency vehicle standards
reflect adoption of tires that progress to the 50th percentile by MY 2027, using steer and drive tire
data for certified emergency vehicles. At these adoption rates, manufacturers need not change
any of the tires they are currently fitting on emergency vehicles, and they will comply on
average.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-75 Projected LRR Tire Adoption Rates for Custom Chassis

MY 2021
MY 2024
MY 2027

Steer
Drive
Steer
Drive
Steer
Drive
Coach
100% LRR
4v
100% LRR
4v
100% LRR 5v
100% LRR 5v
100% LRR
5v
100% LRR 5v
RV
100% LRR
5v
100% LRR
5v
100% LRR 5v
100% LRR 5v
100% LRR
5v
100% LRR 5v
School
100% LRR
4v
100% LRR
2v
100% LRR 5v
100% LRR 3v
100% LRR
5v
100% LRR 4v
Transit
100% LRR
lv
100% LRR
lv
100% LRR lv
100% LRR lv
100% LRR
3v
100% LRR 3v
Refuse
100% LRR
lv
100% LRR
lv
100% LRR lv
100% LRR lv
100% LRR
3v
100% LRR 3v
Mixer
100% LRR
2v
100% LRR
lv
100% LRR 3v
100% LRR lv
100% LRR
3v
100% LRR 2v
Emerge
ncy
100% LRR
2v
100% LRR
lv
100% LRR 3v
100% LRR lv
100% LRR
4v
100% LRR lv
2.9.5.1.4 Workday Idle Reduction
In these rules, the adoption rate of AES for HHD Regional vehicles is 40 percent in MY
2021, 80 percent in MY 2024, and 90 percent in MY 2027. This is because these vehicles have
driving patterns with a significant amount of parked idle, and the vast majority have relatively
modest accessory demands such that only a few would have such large demands for backup
power that turning the engine off while parked would not be feasible. For all weight classes of
Regional vehicles except coach buses, the neutral idle and stop start adoption rates remain zero
in all model years because these vehicles have driving patterns with such a small amount of
transient driving that this drive-idle technology would not provide real world benefits. The LHD
and MHD weight class Regional vehicles carry a 30 percent, 60 percent, and 70 percent adoption
rate of AES in MYs 2021, 2024, and 2027 respectively. The adoption rates of idle reduction
technologies for vocational vehicles in MY 2027 are presented in Table 2-76.
Table 2-76 MY 2027 Adoption Rates of Idle Reduction Technologies

Heavy Heavy-Duty
Medium Heavy-Duty
Light Heavy-Duty
Technology
Regional
Multi-
purpose
Urban
Regional
Multi-
purpose
Urban
Regional
Multi-
purpose
Urban
Neutral Idle
0
70
70
0
60
60
0
60
60
Stop-Start
0
20
20
0
30
30
0
30
30
AES
90
70
70
90
70
70
90
70
70
Although it is possible that a vehicle could have both neutral idle and stop-start, our
stringency calculations only consider emissions reductions where a vehicle either has one or the
other of these technologies. The final GEM input file allows users to apply multiple idle
reduction technologies within a single vehicle configuration.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Because we have included costs to maintain engine protection during periods of shut-off,
as well as over-rides to recognize instances where it may not be safe to shut off an engine, we
believe stop-start can safely be applied at the rates described above in the time frames described.
Also, because we have defined two idle cycles where the automatic engine shutoff technology
addresses the condition of being parked with the service brake off, we believe this alleviates
many of the concerns expressed by commenters about stop-start. We believe many commenters
were (erroneously) imagining that stop-start systems would be required to function during
periods of extended parking.
We agree with commenters that stop-start is not feasible for emergency vehicles and
concrete mixers. We further believe that stop-start would not provide any real world benefit for
coach buses or motor homes. However, for school buses, transit buses, and refuse trucks, we
believe stop-start is feasible and likely to result in real world benefits. The only custom chassis
standards reflecting adoption of AES is school buses, because for the others, we believe the
simple shutdown timer would be likely to trigger an over-ride condition frequently enough to
yield a very small benefit from this technology. To make AES practical for a coach or transit
bus, for example, a much larger auxiliary power source would be needed than the one projected
as part of this rulemaking. We have based the school bus standards in part on adoption of AES,
however. Although many school buses have voluntarily adopted idle reduction strategies for
other reasons, we do not believe many have tamper-proof automatic shutdown systems. The
adoption rates of idle reduction technologies for custom chassis are presented in Table 2-77.
Table 2-77 Custom Chassis Workday Idle Adoption Rates
Technology
MY
AES
NI
Stop-Start
Coach
2021
-
40
-
2027
-
70
-
School
2021
30
60
5
2027
70
60
30
Transit
2021
-
60
10
2027
-
70
30
Refuse
2021
-
30
0
2027
-
50
20
As described above, refuse trucks that do not compact waste are ineligible for the
optional custom chassis vocational vehicle standards. We believe trucks that do not compact
waste have sufficiently low PTO operation (usually only while parked) to make application of
drive idle reduction technologies quite feasible. Front-loading refuse collection vehicles tend to
have a relatively low number of stops per day as they tend to collect waste from central locations
such as commercial buildings and apartment complexes. Because these have a relatively low
amount of PTO operation, we expect stop-start will be reasonably effective for these vehicles.
Rear-loading and side-loading neighborhood waste and recycling collection trucks are the refuse
trucks where the largest number of stop-start and neutral idle over-ride conditions are likely to be
encountered. Because chassis manufacturers, even those with small production volumes and
close customer relationships, do not always know whether a refuse truck chassis will be fitted
with a body designed for front loading, rear loading, or side loading, we are applying an adoption

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
rate of 20 percent stop-start in 2027 to refuse trucks certified as custom chassis. Chassis
manufacturers certifying refuse trucks to the optional custom chassis standards may enter Yes in
the input field in GEM for stop-start and the effectiveness will be computed based on the default
350 hp engine with 5-speed HHD automatic transmission. In the case where a chassis
manufacturer certifies a refuse truck to the primary standards under the HHD Urban subcategory,
the MY 2027 adoption rate is also 20 percent, and the stringency assumes a sufficiently capable
stop-start system to not require an excessive use of over-rides. Manufacturers opting to certify
refuse trucks to the primary standards will have an option to be recognized for enhanced stop-
start systems through the powertrain test.
It may take some minor development effort to apply neutral idle to high-torque automatic
transmissions designed for the largest vocational vehicles. Based on stakeholder input, the
designs needed to avoid an uncomfortable re-engagement bump when returning to drive from
neutral may require some engineering refinement as well as some work to enable two-way
communication between engines and transmissions. Nonetheless, this technology should be
available in the near term for many vehicles and is low cost compared to many other
technologies we considered. Commenters asked for over-rides such as when on a steep hill, and
we agree and are adopting this provision.
We see the above idle reduction technologies being technically feasible on the majority
of vocational vehicles, and especially effective on those with the most time in drive-idle in their
workday operation. Although we are not prepared to predict what fraction of vehicles will adopt
stop-start in the absence of Phase 2, the agencies are confident that this technology, which is on
the entry-level side of the hybrid and electrification spectrum, will be widely available in the
Phase 2 time frame.
Based on these projected adoption rates and the effectiveness values described above in
this section, we expect overall GHG and fuel consumption reductions from workday idle on
vocational vehicles to range from one to 13 percent in MY 2027.
2.9.5.1.5 Weight Reduction
As described in the RIA Chapter 2.11.10.3, weight reduction is a relatively costly
technology, at approximately $3 to $10 per pound for a 200-lb package. Even so, for vehicles in
service classes where dense, heavy loads are frequently carried, weight reduction can translate
directly to additional payload. The agencies project that modest weight reduction is feasible for
all vocational vehicles. The agencies are predicating the final standards on adoption of weight
reduction comparable to what can be achieved through use of aluminum wheels. This package is
estimated at 150 pounds for LHD and MHD vehicles, and 250 pounds for HHD vehicles, based
on six and 10 wheels, respectively. In MY 2021, we project an adoption rate of 10 percent, 30
percent in MY 2024, and 50 percent in MY 2027.
The agencies project that manufacturers will have sufficient options of other components
eligible for material substitution so that this level of weight reduction will be feasible even where
aluminum wheels are not selected by customers. Based on comments, we have removed
aluminum transmission cases and aluminum clutch housings from the vocational lookup table in
the regulations at 40 CFR 1037.520.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The only custom chassis standards on which we are predicating the standard on use of
weight reduction is transit buses. In addition to compelling comment from UCS, we considered
information from a 2014 study conducted by the APTA, where researchers found that fewer than
half of all transit bus models comply with a 20,000 pound single axle weight limit when empty
(i.e., at curb weight) and nearly all rear axles on transit buses longer than 35 feet exceed 24,000
pounds. According to APTA, the transit bus manufacturing industry has undertaken significant
research and development activities directed at decreasing the curb weight of transit buses, and
future opportunities to reduce transit bus curb weight include the use of lighter weight materials
and alternative manufacturing techniques, but any weight reductions are expected to be costly for
the manufacturing industry.176 Because overloaded axles is a significant issue for transit buses,
we believe it is appropriate for these rules to recognize it and provide a regulatory driver for
lightweighting in this sector.
We have learned that manufacturers of concrete mixers, refuse trucks, and some high end
buses have already made extensive use of lightweighting technologies in the baseline fleet. We
also received persuasive comment cautioning us not to base the school bus standards on weight
reduction due to potential conflicts with safety standards. In considering this information, we are
allowing all vehicles certified using custom chassis regulatory subcategory identifiers to make
use of weight reduction as a compliance flexibility, but only predicating standard stringency for
transit buses on use of aluminum wheels at the same adoption rate as for the primary program.
2.9.5.1.6	Electrified Accessories
The agencies are predicating the final vocational vehicle standards in part on an adoption
rate of five percent in MY 2021 of an electrified accessory package that achieves one percent
fuel efficiency improvement. The previous discussion in Chapter 2.9.3.6 describes some pre-
defined e-accessory improvements that are available in GEM for all vocational vehicles. In MY
2024 we increase this adoption rate to ten percent, and in MY 2027 the projected adoption rate is
15 percent, applicable in all subcategories excluding custom chassis. Although we believe some
components could be electrified for some custom chassis, we do not have sufficient information
to estimate an incremental cost associated with electrifying the more complex systems on custom
chassis such as buses, or to project a specific adoption rate for this type of improvement.
2.9.5.1.7	Tire Pressure Systems
The agencies are predicating the vocational vehicle standards in part on widespread
adoption of tire pressure monitoring systems. These are readily accepted by fleets as a cost-
effective safety and fuel-saving measure. Because there may be some minor challenges in
applying this technology to some vehicles where the payload and duty cycle lead to very high
tire temperatures and pressures (as described above), we are applying a lower adoption rate to
Urban and Multi-purpose vehicles than to Regional vehicles, as shown in Table 2-78. We are
applying similarly lower adoption rates for refuse trucks and transit buses. We are not
predicating the emergency vehicle or cement mixer standards on adoption of TPMS.
We are predicating the optional school bus, coach bus, transit bus, and refuse truck
standards in part on limited adoption of automatic tire inflation systems (ATIS), as shown in

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-78. These are more costly than TPMS, and require an onboard air supply and sometimes
extensive plumbing of air lines.
Table 2-78 Vocational Tire Pressure System Adoption Rates
Technology
TPMS
ATIS

MY 2021
MY 2024
MY
2027
MY
2021
MY
2024
MY
2027
Regional
60
75
90
-
-
-
Multi-Purpose
50
65
80
-
-
-
Urban
40
55
70
-
-
-
School
70

80
-

20
Coach
50

75
10

25
Transit
40

50
10

20
Refuse
40

50
10

15
Motor Home
60

90
-

-
2.9.5.1.8 HFC L eakage
We project 100 percent adoption rate in all implementation years of the Phase 2 program
for use of low leakage air conditioning system components to reduce direct emissions of HFC
compounds from vocational vehicles.
2.9.6 Vocational Vehicle Standards
The derivation of the vocational vehicle standards incorporates several methods because
some GEM inputs lend themselves to fleet-average values, some are vehicle specific (either on
or off) and some improvements are not directly modeled in GEM. For each model year of
standards, the agencies derived a scenario vehicle for each subcategory using the future model
year engine map with fleet average input values for tire rolling resistance and weight reduction.
For example, the MY 2021 HHD weight reduction input value was derived as follows: 210
pounds times 10 percent adoption yields 21 pounds. Those scenario vehicle performance results
were combined in a post-process method with subcategory-specific improvements from idle
reduction, axle disconnect, torque converter lockup, and transmission automation, using directly
modeled GEM improvements comparing results with these technologies on or off the scenario
vehicle. Subsequently, these performance values were combined with estimated improvement
values of technologies not modeled in GEM, including TPMS, hybrids, and transmission gear
efficiency.
The set of fleet-average inputs for tire CRR and weight reduction for MY 2021, as
modeled in GEM is shown in Table 2-79, along with the respective adoption rates for idle
reduction, axle disconnect, and torque converter lockup. The agencies derived the level of the
MY 2024 standards by using the GEM inputs and adoption rates shown in Table 2-80 below.
The agencies derived the level of the MY 2027 standards by using the GEM inputs and adoption
rates shown in Table 2-81, below. Post-processing improvements for technologies not directly
modeled, including TPMS, e-accessories, hybrids, and axle and transmission improvements are

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
presented as a combined driveline improvement factor in Table 2-82 below. The values in this
table for Si-powered vocational vehicles include improvements due to adoption of SI engine
technology.
After obtaining individual GEM performance values for each of the subcategories, the
agencies conducted fleet-mix averaging described in the Preamble in Section V.C. The resulting
final vocational vehicle standards are presented in Table 2-83 through Table 2-88.
Table 2-79 GEM Inputs Used to Derive MY 2021 Vocational Vehicle Standards
CLASS 2B-5
CLASS 6-7
CLASS 8
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-Purpose
Regional
SI Engine



2018 MY 6.8L, 300 hp engine



CI Engine
2021 MY 7L, 200 hp Engine
2021 MY 7L, 270 hp Engine
2021 MY
11L, 350
hp
Engine
2021 MY 11L, 350 hp
Engine and 2021 MY 15L
455hp Engine3
Torque Converter Lockup in 1st (adoption rate)
30%
30%
30%
30%
30%
30%
10%
10%
0%
6x2 Disconnect Axle (adoption rate)
0%
0%
0%
0%
0%
0%
0%
5%
10%
AES (adoption rate)
30%
30%
40%
30%
30%
40%
30%
30%
40%
Stop-Start (adoption rate)
10%
10%
0%
10%
10%
0%
0%
0%
0%
Neutral Idle (adoption rate)
50%
50%
0%
50%
50%
0%
50%
50%
0%
Steer Tires (CRR kg/metric ton)
7
6.8
6.8
6.8
6.7
6.7
6.4
6.2
6.2
Drive Tires (CRR kg/metric ton)
7.2
6.9
6.9
7.8
7.5
7.5
7.8
7.5
7.5
Weight Reduction (lb)
15
15
15
15
15
15
25
25
25
Note:
a The Multipurpose and Regional HHD standards are established using averages of configurations with different
engines as described in Table 2-55.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-80 GEM Inputs Used to Derive MY 2024 Vocational Vehicle Standards
CLASS 2B-5
CLASS 6-7
CLASS 8
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-Purpose
Regional
SI Engine



2018 MY 6.8L, 300 hp engine



CI Engine
2024 MY 7L, 200 hp Engine
2024 MY 7L, 270 hp Engine
2024 MY
11L, 350
hp
Engine
2024 MY 11L, 350 hp
Engine and 2024 MY 15L
455hp Engine3
Torque Converter Lockup in 1st (adoption rate)
40%
40%
40%
40%
40%
40%
20%
20%
0%
6x2 Disconnect Axle (adoption rate)
0%
0%
0%
0%
0%
0%
0%
15%
20%
AES (adoption rate)
60%
60%
80%
60%
60%
80%
60%
60%
80%
Stop-Start (adoption rate)
20%
20%
0%
20%
20%
0%
10%
10%
0%
Neutral Idle (adoption rate)
70%
70%
0%
70%
70%
0%
70%
70%
0%
Steer Tires (CRR kg/metric ton)
7.0
6.8
6.2
6.8
6.7
6.2
6.4
6.2
6.2
Drive Tires (CRR kg/metric ton)
7.2
6.9
6.9
7.8
7.5
6.9
7.8
7.5
6.9
Weight Reduction (lb)
45
45
45
45
45
45
75
75
75
Note:
a The Multipurpose and Regional HHD standards are established using averages of configurations with different
engines as described in Table 2-55.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-81 GEM Inputs Used to Derive MY 2027 Vocational Vehicle Standards
CLASS 2B-5


CLASS 6-7



CLASS


Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
SI Engine
2018 MY 6.8L, 300 hp engine
CI Engine
2027 MY 7L, 200 hp Engine
2027 MY 7L, 270 hp Engine
2027 MY
11L, 350
hp
Engine3
2027 MY 11L, 350 hp
Engine and
2027 MY 15L 455hp
Engine3
Torque Converter Lockup in 1st (adoption rate)
50%
50%
50%
50%
50%
50%
30%
30%
0%
6x2 Disconnect Axle (adoption rate)
0%
0%
0%
0%
0%
0%
0%
25%
30%
AES (adoption rate)
70%
70%
90%
70
70%
90%
70%
70%
90%
Stop-Start (adoption rate)
30%
30%
0%
30%
30%
0%
20%
20%
0%
Neutral Idle (adoption rate)
60%
60%
0%
60%
60%
0%
70%
70%
0%
Steer Tires (CRR kg/metric ton)
6.8
6.2
6.2
6.7
6.2
6.2
6.2
6.2
6.2
Drive Tires (CRR kg/metric ton)
6.9
6.9
6.9
7.5
6.9
6.9
7.5
6.9
6.9
Weight Reduction (lb)
75
75
75
75

75

75
125

125

125
Note:
a The Multipurpose and Regional HHD standards are established using averages of configurations with different
engines as described in Table 2-55.
In applying improvements due to technologies that were directly simulated in GEM but
required post-processing to account for adoption rates less than 100 percent, each improvement
was applied multiplicatively to the performance of the scenario vehicle that already had the
improved tires, weight, and engine. The formula used follows the pattern illustrated in Equation
2-2. Similarly, the improvements due to technologies not modeled in GEM were included in this
equation as noted. As described above in Chapter 2.9.3.1 for applicable technologies, the
agencies used an energy-weighted and cycle-weighted average estimating method using cycle-
specific CO2 emissions reported in the GEM output file for baseline vehicles. For the idle
cycles, the development version of GEM provides emissions in grams per hour. For the driving
cycles, GEM provides emissions in grams per ton-mile. By multiplying those values by the
average speed of each cycle and the default payload, GEM outputs in grams per ton-mile for the
driving cycles are converted to grams per hour, and these are surrogates for the energy expended
over those cycles. For example, in the medium heavy-duty Multipurpose subcategory with a
payload of 5.6 tons, the baseline vehicle configuration has cycle-specific results of 284 g
CCh/ton-mile for the transient cycle, 202 g CCh/ton-mile for the 55 cycle, 243 g CCh/ton-mile
for the 65 cycle, 10,226 g/hr for drive idle, and 5,284 g/hr for parked idle. By summing the
products of the percent improvement expected over each cycle, the CO2 emitted while

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
completing the cycle, and the associated composite weighting of the cycle, and dividing by the
sum of the products of the CO2 emitted and cycle weightings, we obtain subcategory-specific
improvement values for each technology. The complete set of calculations is available in the
docket.177
Equation 2-2: Additional percent improvement beyond engine, tires, weight:
l-((l-DIF)*(l-AESa*AESe)*(l-NIa*NIe)*(l-SSa*SSe)*(l-NMTa*NMTe)*(l-TLa*TLe)*(l-ADa*ADe))
Where:
•	DIF is the driveline improvement factor derived using engineering calculations,
not directly modeled in GEM
•	AESa and AESe are the adoption rate and effectiveness, respectively, in percent,
of automatic engine shutdown, as modeled in GEM
•	NIa and NIe are the adoption rate and effectiveness, respectively, in percent, of
neutral idle, as modeled in GEM
•	SSa and SSe are the adoption rate and effectiveness, respectively, in percent, of
stop-start, as modeled in GEM
•	NMTa and NMTe are the adoption rate and effectiveness, respectively, in percent,
of a non-manual transmission, as modeled in GEM
•	TLa and TLe are the adoption rate and effectiveness, respectively, in percent, of
torque converter lockup in first gear, as modeled in GEM
•	ADa and ADe are the adoption rate and effectiveness, respectively, in percent, of
axle disconnect, as modeled in GEM
Table 2-82 Vocational Driveline Improvement Factors

Class 2b-5
Class 6-7
Class 8

Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
CI 2021
0.019
0.018
0.018
0.019
0.019
0.019
0.019
0.018
0.017
CI 2024
0.041
0.036
0.029
0.041
0.036
0.029
0.040
0.036
0.026
CI 2027
0.061
0.053
0.037
0.061
0.053
0.037
0.060
0.052
0.034
SI 2021
0.027
0.026
0.026
0.028
0.027
0.027



SI 2024
0.048
0.044
0.037
0.049
0.044
0.037



SI 2027
0.067
0.059
0.045
0.068
0.060
0.045



Table 2-83 and Table 2-84 present EPA's CO2 standards and NHTSA's fuel consumption
standards, respectively, for chassis manufacturers of Class 2b through Class 8 vocational
vehicles for the beginning model year of the program, MY 2021.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-83 EPA CO2 Standards for MY2021 Class 2b-8 Vocational Vehicles
EPA Standard For Vehicle With CI Engine Ef
bctive MY2021 (gram C02/ton-mile)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
424
296
308
Multi-Purpose
373
265
261
Regional
311
234
205
EPA Standard for Vehicle with SI Engine Effective MY2021 (gram CCh/ton-mile)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
461
328

Multi-Purpose
407
293

Regional
335
261

Table 2-84 NHTSA Fuel Consumption Standards for MY2021 Class 2b-8 Vocational Vehicles
NHTSA STANDARD FOR VEHICLE WITH CI ENGINE EFFECTIVE MY 2021 (FUEL
CONSUMPTION GALLON PER 1,000 TON-MILE)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
41.6503
29.0766
30.2554
Multi-Purpose
36.6405
26.0314
25.6385
Regional
30.5501
22.9862
20.1375
NHTSA Standard for Vehicle with SI Engine
1,000 ton-mile)
iffective MY 2021 (Fuel Consumption gallon per
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
51.8735
36.9078

Multi-Purpose
45.7972
32.9695

Regional
37.6955
29.3687

EPA's vocational vehicle CO2 standards andNHTSA's fuel consumption standards for
the MY 2024 stage of the program are presented in Table 2-85 and Table 2-86, respectively.
These reflect broader adoption rates of vehicle technologies already considered in the technology
basis for the MY 2021 standards. The standards for vehicles powered by CI engines also reflect
that in MY 2024, the separate engine standard would be more stringent, so the vehicle standard
keeps pace with the engine standard.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-85 EPA CO2 Standards for MY2024 Class 2b-8 Vocational Vehicles
EPA STANDARD FOR VEHICLE WITH CI ENGINE EFFECTIVE MY2024 (GRAM
CO2/TON-MILE)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
385
271
283
Multi-Purpose
344
246
242
Regional
296
221
194
EPA Standard for Vehicle with SI Engine Effective MY2024 (gram CC^/ton-mile)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
432
310

Multi-Purpose
385
279

Regional
324
251

Table 2-86 NHTSA Fuel Consumption Standards for MY2024 Class 2b-8 Vocational Vehicles
NHTSA STANDARD FOR VEHICLE WITH CI ENGINE EFFECTIVE MY 2024 (FUEL
CONSUMPTION GALLON PER 1,000 TON-MILE)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
37.8193
26.6208
27.7996
Multi-Purpose
33.7917
24.1650
23.7721
Regional
29.0766
21.7092
19.0570
NHTSA Standard for Vehicle with SI Engine
1,000 ton-mile)
iffective MY 2024 (Fuel Consumption gallon per
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
48.6103
34.8824

Multi-Purpose
43.3217
31.3942

Regional
36.4577
28.2435

EPA's vocational vehicle CO2 standards andNHTSA's fuel consumption standards for
the full implementation year of MY 2027 are presented in Table 2-87 and Table 2-88,
respectively. These reflect even greater adoption rates of the same vehicle technologies
considered in the basis for the previous stages of the Phase 2 standards. The MY 2027 standards
for vocational vehicles powered by CI engines reflect additional engine technologies consistent
with those on which the separate MY 2027 CI engine standard is based.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-87 EPA CO2 Standards for MY2027 Class 2b-8 Vocational Vehicles
EPA STANDARD FOR VEHICLE WITH CI ENGINE EFFECTIVE MY2027 (GRAM
CO2/TON-MILE)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
367
258
269
Multi-Purpose
330
235
230
Regional
291
218
189
EPA Standard for Vehicle with SI Engine Effective MY2027 (gram CC^/ton-mile)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
413
297

Multi-Purpose
372
268

Regional
319
247

Table 2-88 NHTSA Fuel Consumption Standards for MY2027 Class 2b-8 Vocational Vehicles
NHTSA STANDARD FOR VEHICLE WITH CI ENGINE EFFECTIVE MY 2027 (FUEL
CONSUMPTION GALLON PER 1,000 TON-MILE)
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7
Heavy Heavy-Duty
Class 8
Urban
36.0511
25.3438
26.4244
Multi-Purpose
32.4165
23.0845
22.5933
Regional
28.5855
21.4145
18.5658
NHTSA Standard for Vehicle with SI Engine
1,000 ton-mile)
iffective MY 2027 (Fuel Consumption gallon per
Duty Cycle
Light Heavy-Duty
Class 2b-5
Medium Heavy-Duty
Class 6-7 (and C8
Gasoline)

Urban
46.4724
33.4196

Multi-Purpose
41.8589
30.1564

Regional
35.8951
27.7934

2.9.6.1 GEM-Based Custom Chassis Standards
Table 2-89 and Table 2-90 present EPA's CO2 standards and NHTSA's fuel consumption
standards, respectively, for custom vocational chassis. These standards may be selected by
custom chassis manufacturers, who retain the option of electing to certify to the primary
standards. (As already noted, these custom chassis vehicles will be required to use engines
meeting the Phase 2 engine standards, and thus, should generally incorporate the same engine
improvements as other vocational vehicles). The agencies have analyzed the technological
feasibility of achieving these optional fuel consumption and CO2 standards, based on projections
of actions manufacturers may take to reduce fuel consumption and emissions to achieve the

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
standards, and believe that the standards are technologically feasible throughout the regulatory
useful life of the program.
These custom vehicle-level standards are predicated on a simpler set of vehicle
technologies than the primary Phase 2 standard for vocational vehicles. In developing these
optional standards, the agencies have evaluated the current levels of fuel consumption and
emissions, the kinds of technologies that could be utilized by manufacturers to reduce fuel
consumption and emissions, the associated lead time, the associated costs for the industry, fuel
savings for the owner/operator, and the magnitude of the CO2 reductions and fuel savings that
may be achieved. After examining the possibilities of vehicle improvements, the agencies are
basing the vehicle-level standards for coach buses, motor homes, school buses, transit buses, and
refuse trucks on the performance of workday idle reduction technologies, tire pressure systems,
simplified transmission improvements, and further tire rolling resistance improvements. The
agencies are basing the standards for concrete mixers and emergency vehicles on use of tires
with current average levels of rolling resistance. The EPA-only air conditioning standard is
based on leakage improvements. Of these technologies, we believe that improved tire rolling
resistance, neutral idle, and air conditioning leakage improvements are available today and may
be adopted as early as MY 2021. The vehicle technology that we believe will benefit from more
development time for engine and vehicle integration is stop-start idle reduction.
The MY 2024 standards reflect broader adoption rates of vehicle technologies already
considered in the technology basis for the MY 2021 standards. EPA's custom chassis CO2
standards and NHTSA's fuel consumption standards for the full implementation year of MY
2027 reflect even greater adoption rates of the same vehicle technologies considered as the basis
for the MY 2024 standards.
As with the other regulatory categories of heavy-duty vehicles, NHTSA and EPA are
adopting standards that apply to custom chassis vocational vehicles at the time of production,
and EPA is adopting standards for a specified period of time in use (e.g., throughout the
regulatory useful life of the vehicle).
The optional standards shown below were derived using baseline vehicle models with
many attributes similar to those developed for the primary program, as described above in
Chapter 2.9.2. For better transparency with respect to the incremental difference between the
MY 2021 and MY 2027 vehicle standards, we have modeled a certified MY 2027 engine for
both vehicle model years of optional custom chassis standards. Thus, chassis manufacturers who
do not make their own engines may compare the two model years of standards presented in
Table 2-89 and Table 2-90 and know that any differences are due solely to vehicle-level
technologies.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-89 EPA Emission Standards for Custom Chassis (gram CCh/ton-mile)

MY 2021
MY 2027
Coach Bus
210
205
Motor Home
228
226
School Bus
291
271
Transit
300
286
Refuse
313
298
Mixer
319
316
Emergency
324
319
Table 2-90 NHTSA Fuel Consumption Standards for Custom Chassis (gallon per 1,000 ton-mile)

MY 2021
MY 2027
Coach Bus
20.6287
20.1375
Motor Home
22.3969
22.2004
School Bus
28.5855
26.6208
Transit
29.4695
28.0943
Refuse
30.7466
29.2731
Mixer
31.3360
31.0413
Emergency
31.8271
31.3360
2.9.6.2 Summary of Vocational Vehicle Package Costs
The agencies have estimated the costs of the technologies that could be used to comply
with the final Phase 2 vocational vehicle standards. The estimated costs are shown in Table 2-91
for MY2021, in for MY2024, and for MY 2027. Fleet average costs are shown for light,
medium and heavy HD vocational vehicles in each duty-cycle-based subcategory - Urban,
Multi-Purpose, and Regional. As shown in Table 2-91, in MY 2021 these range from
approximately $900 for MHD and LHD Regional vehicles, up to $2,600 for HHD Regional
vehicles. Those two lower-cost packages reflect zero hybrids, and the higher-cost package
reflects significant adoption of automated transmissions. Many changes have been made to the
cost estimates since proposal. In the RIA Chapter 2.12.2, the agencies present vocational vehicle
technology package costs differentiated by MOVES vehicle type. These costs do not indicate the
per-vehicle cost that may be incurred for any individual technology. For more specific
information about the agencies' estimates of per-vehicle costs, please see the RIA Chapter 2.11.
The engine costs listed represent the cost of an average package of diesel engine technologies as
set out in RIA Chapter 2.7.7. Individual technology adoption rates for engine packages are
described in RIA Chapter 2.9.1.2.2. For gasoline vocational vehicles, the agencies are projecting
adoption of engine improvements that are reflected exclusively in the vehicle standard, see
Chapter 2.9.1.2.1 above) for an estimated $138 added to the average SI vocational vehicle
package cost beginning in MY 2021.
The details behind all these costs are presented in RIA Chapter 2.11, including the
markups and learning effects applied and how the costs shown here are weighted to generate an

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
overall cost for the vocational segment. These estimates have changed significantly from those
presented in the proposal, due to changes in projected technology adoption rates as well as
changes in direct costs that reflect comments received.
Table 2-91 Technology Package Incremental Costs for Vocational Vehicles for MY2021a b (2013$)

LIGHT HD
MEDIUM HD

HEAVY HD

Urban
Multi-
purpose
Regiona
1
Urban
Multi-
purpose
Regiona
1
Urban
Multi-
purpose
Regional
Engine0
$298
$298
$298
$275
$275
$275
$275
$275
$275
Tires
$0
$27
$27
$9
$9
$9
$13
$13
$13
Tire Pressure
Monitoring
$123
$154
$184
$123
$154
$184
$233
$292
$350
Transmission
$217
$217
$217
$217
$217
$217
$186
$413
$1,519
Axle related
$13
$13
$13
$13
$13
$13
$20
$26
$32
Weight
Reduction
$69
$69
$69
$69
$69
$69
$250
$250
$250
Idle reduction
$155
$155
$12
$160
$160
$12
$68
$68
$12
Hybridization
$178
$178
$0
$178
$178
$0
$178
$178
$0
Air
Conditioning11
$22
$22
$22
$22
$22
$22
$22
$22
$22
Other6
$30
$30
$30
$49
$49
$49
$89
$89
$89
Total
$1,106
$1,164
$873
$1,116
$1,146
$851
$1,334
$1,625
$2,562
Notes:
a Costs shown are for the 2021 model year and are incremental to the costs of a vehicle meeting the Phase 1 standards. These
costs include indirect costs via markups along with learning impacts. For a description of the markups and learning impacts
considered in this analysis and how it impacts technology costs for other years, refer to RIA Chapter 2.11.
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated vehicle subcategories.
c Engine costs shown are for a light HD, medium HD or heavy HD diesel engines. For gasoline-powered vocational vehicles we
are projecting $139 of additional engine-based costs beyond Phase 1.
d EPA's air conditioning standards are presented in Preamble Section V.C.
e Other incremental technology costs include electrified accessories and advanced shift strategy.
Table 2-92 presents estimated incremental costs for MY2024 for light, medium and
heavy HD vocational vehicles in each duty-cycle-based subcategory - Urban, Multi-Purpose,
and Regional. As shown, these range from approximately $1,300 for MHD and LHD Regional
vehicles, up to $4,000 for HHD Regional vehicles. The increased costs above the MY 2021
values reflect increased adoption rates of individual technologies, while the individual
technology costs are generally expected to remain the same or decrease, as explained in the RIA
Chapter 2.11. For example, Chapter 2.11.7 presents MY 2024 hybridization costs that range
from $6,046 to $15,872 per vehicle for vocational vehicles.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-92 Technology Package Incremental Costs for Vocational Vehicles for MY2024a b (2013$)

LIGHT HD
MEDIUM HD
HEAVY HD

Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Engine0
$446
$446
$446
$413
$413
$413
$413
$413
$413
Tires
$0
$31
$33
$10
$10
$33
$13
$13
$53
Tire Pressure
Monitoring
$155
$183
$211
$155
$183
$211
$294
$347
$401
Transmission
$276
$276
$276
$276
$276
$276
$222
$1,032
$2,193
Axle related
$24
$24
$24
$24
$24
$24
$37
$54
$60
Weight
Reduction
$186
$186
$186
$186
$186
$186
$684
$684
$684
Idle reduction
$248
$248
$21
$256
$256
$21
$242
$242
$21
Hybridization
$550
$550
$0
$653
$653
$0
$844
$844
$0
Air
Conditioning11
$20
$20
$20
$20
$20
$20
$20
$20
$20
Othere
$54
$54
$54
$89
$89
$89
$162
$162
$162
Total
$1,959
$2,018
$1,272
$2,082
$2,110
$1,274
$2,932
$3,813
$4,009
Notes:
a Costs shown are for the 2024 model year and are incremental to the costs of a vehicle meeting the Phase 1 standards. These
costs include indirect costs via markups along with learning impacts. For a description of the markups and learning impacts
considered in this analysis and how it impacts technology costs for other years, refer to RIA Chapter 2.11.
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated vehicle subcategories.
c Engine costs shown are for a light HD, medium HD or heavy HD diesel engines. For gasoline-powered vocational vehicles we
are projecting $136 of additional engine-based costs beyond Phase 1.
d EPA's air conditioning standards are presented in Preamble Section V.C.
e Other incremental technology costs include electrified accessories and advanced shift strategy.
Table 2-93 presents estimated incremental costs for MY2027 for light, medium and
heavy HD vocational vehicles in each duty-cycle-based subcategory - Urban, Multi-Purpose,
and Regional. As shown, these range from approximately $1,500 for MHD and LHD Regional
vehicles, up to $5,700 for HHD Regional vehicles. Although the Multipurpose and Urban
subcategories are projected to adopt some high-cost technologies such as hybrids, the HHD
Regional package comes out more costly because it reflects 90 percent adoption of automated
transmissions. The engine costs shown represent the average costs associated with the MY 2027
vocational diesel engine standard described in Section II.D of the Preamble. For gasoline
vocational vehicles, the agencies are projecting adoption of engine technologies with an
estimated $125 added to the average SI vocational vehicle package cost in MY 2027. Further
details on how these SI vocational vehicle costs were estimated are provided above in Chapter
2.9.1.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-93 Technology Package Incremental Costs for Vocational Vehicles for MY2027a b (2013$)

LIGHT HD
MEDIUM HD
HEAVY HD

Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Urban
Multi-
purpose
Regional
Engine0
$481
$481
$481
$446
$446
$446
$446
$446
$446
Tires
$12
$24
$24
$6
$24
$24
$12
$36
$36
Tire Pressure
Monitoring
$187
$214
$240
$187
$214
$240
$355
$405
$456
Transmission
$271
$271
$293
$271
$271
$293
$220
$990
$3,269
Axle related
$35
$35
$35
$35
$35
$35
$52
$82
$87
Weight
Reduction
$294
$294
$294
$294
$294
$294
$1,102
$1,102
$1,102
Idle
reduction
$303
$303
$23
$314
$314
$23
$365
$365
$23
Hybridization
$857
$857
$0
$1,032
$1,032
$0
$1,353
$1,353
$0
Air
Conditioning
d
$20
$20
$20
$20
$20
$20
$20
$20
$20
Other6
$73
$73
$77
$122
$122
$127
$227
$227
$231
Total
$2,533
$2,571
$1,486
$2,727
$2,771
$1,500
$4,151
$5,025
$5,670
Notes:
a Costs shown are for the 2027 model year and are incremental to the costs of a vehicle meeting the Phase 1 standards. These
costs include indirect costs via markups along with learning impacts. For a description of the markups and learning impacts
considered in this analysis and how it impacts technology costs for other years, refer to RIA Chapter 2.11.
b Note that values in this table include projected technology penetration rates. Therefore, the technology costs shown reflect the
average cost expected for each of the indicated vehicle subcategories.
c Engine costs shown are for a light HD, medium HD or heavy HD diesel engines. For gasoline-powered vocational vehicles we
are projecting $125 of additional engine-based costs beyond Phase 1.
d EPA's air conditioning standards are presented in Preamble Section V.C.
e Other incremental technology costs include electrified accessories and advanced shift strategy.
2.10 Technology Application and Estimated Costs - Trailers
The agencies are adopting standards for trailers specifically designed to be pulled by
Class 7 and 8 tractors. These standards are expressed as CO2 and fuel consumption standards,
and would apply to each trailer with respect to the emissions and fuel consumption that would be
expected for a specific standard type of tractor pulling such a trailer. EPA and NHTSA believe it
is appropriate to establish standards for trailers separately from tractors because they are
separately manufactured by distinct companies which control every aspect of their design and
thus are the appropriate entity to certify compliance; the agencies are not aware of any
manufacturers that currently assemble both the finished tractor and the trailer. The legal basis
for setting separate standards for trailers is discussed in the Preamble in Section I.E. This section
of the RIA describes the analyses performed by the agencies as we developed the trailer
program.
2.10.1 Trailer Subcategories Evaluated
The agencies evaluated several trailer subcategories for these rules. Though many of the
same technologies are available for dry and refrigerated vans, the agencies evaluated these trailer

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
types separately. The transport refrigeration unit (TRU) commonly located at the front of
refrigerated trailers adds weight, has the potential to impact the aerodynamic characteristics of
the trailer, and may limit the types of aerodynamic devices that can be applied. Additionally,
"long box" vans in lengths 50 feet or longer and "short box" vans less than 50 feet in length were
evaluated separately due to differences in both weight and use patterns. We have chosen 53-foot
box vans to represent all long box vans in both compliance modeling and testing. Short box vans
are represented by solo 28-foot vans. The agencies did test other trailer lengths and the results
are presented in this chapter.
The agencies identified a list of work-performing devices that are sometimes added to
standard box vans, which may inhibit the use of some aerodynamic devices. Trailer
manufacturers may designate box vans that are restricted from using aerodynamic devices in one
location on the trailer as "partial-aero" box vans. We believe these trailers have the ability to
adopt single aerodynamic technologies, but do not expect them to be able to meet the same
stringencies as the "full-aero" box vans throughout the program.
Additionally, manufacturers may designate box vans that have work-performing devices
in two locations such that they inhibit the use of all practical aerodynamic devices as "non-aero"
box vans that would not be expected to adopt aerodynamic technologies at any point in the
program. These trailers have standards based on the use of tire technologies only. Similarly, we
recognize the potential for CO2- and fuel consumption reduction from three non-box trailers
(e.g., tankers, flatbeds, and container chassis). Standards for these non-box trailers are also based
on the use of tire technologies and do not reflect the use of aerodynamic technologies.
In summary, the agencies are adopting standards for ten trailer subcategories:
-	Long box (longer than 50 feet) dry vans
-	Long box (longer than 50 feet) refrigerated vans
-	Short box (50 feet and shorter) dry vans
-	Short box (50 feet and shorter) refrigerated vans
-	Partial-aero long box dry vans
-	Partial-aero long box refrigerated vans
-	Partial-aero short box dry vans
-	Partial-aero short box refrigerated vans
-	Non-aero box vans (all lengths of dry and refrigerated vans)
-	Non-box trailers (tanker, platform, container chassis only)
The analysis in the following sections describes our evaluation of the cost and
effectiveness of the technologies used in the design of the Phase 2 trailer program. We conclude
with a description of the development of our GEM-based equation that box van manufacturers
will use for compliance.
2.10.2 Defining the Trailer Technology Packages
The impact of a trailer on the overall fuel efficiency and CO2 emissions of a tractor-
trailer vehicle varies depending on three main characteristics of the trailer: aerodynamic drag,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
tire rolling resistance, and weight. In this section, we outline the technologies that address these
characteristics and the ones the agencies evaluated for the standards.
2.10.2.1 Aerodynamic Drag Reduction
The rigid, rectangular shape of box vans creates significant aerodynamic drag and makes
them ideal candidates for aerodynamic technologies that can reduce drag and improve fuel
consumption and CO2 emissions. Current aerodynamic technologies for box vans have shown
significant drag reductions, as discussed below. These technologies are designed to create a
smooth transition of airflow from the tractor, around the trailer, and beyond the trailer. Box vans
provide opportunities to address drag at the front, rear, and underside of the trailer, and the
agencies considered several types of aerodynamic devices designed to address drag at all of these
points. Table 2-94 lists common aerodynamic technologies for use on box vans and a
description of their intended impact. Several versions of each of these technologies are
commercially available and have seen increased adoption over the past decade. Performance of
these devices varies based on their design, their location and orientation on the trailer, and the
vehicle speed.
Table 2-94 Common Bolt-on Aerodynamic Technologies for Box Trailers
LOCATION
ON TRAILER
EXAMPLE TECHNOLOGIES
INTENDED IMPACT ON AERODYNAMICS
Front
Front fairings and gap-reducing
fairings
Reduce cross-flow through gap and smoothly
transition airflow from tractor to the trailer
Rear
Rear fairings, boat tails and flow
diffusers
Reduce pressure drag induced by the trailer wake
Underside
Side fairings and skirts, and
underbody devices
Manage flow of air underneath the trailer to reduce
turbulence, eddies and wake
2.10.2.1.1 Comparison of Technology Performance: SmartWay-Verification
and GEM Results
SmartWay-verified technologies are evaluated on 53-foot dry vans. The verified
technologies are grouped into bins that represent one percent, four percent, or five percent fuel
savings relative to a typical long-haul tractor-trailer at 65-mph cruise conditions. Use of verified
aerodynamic devices totaling at least five percent fuel savings, along with verified tires, qualifies
a 53-foot dry van trailer for the "SmartWay Trailer" designation. In 2014, EPA expanded the
program to include refrigerated vans and provided a "SmartWay Elite" designation if fleets adopt
verified tires and aerodynamic equipment providing nine percent or greater fuel savings. To-
date, ten aerodynamic technology packages from six manufacturers have received the SmartWay
Elite designation. We may refer to SmartWay verification levels in this analysis, since the trailer
industry is most familiar with these values as a measure of trailer performance.
It is important to note that the cruise speed results presented in SmartWay do not
necessarily match the results of EPA's Greenhouse gas Emissions Model (GEM), which is the
tool the agencies will use for trailer standard development and compliance evaluation. Figure
2-56 shows a comparison of the CO2 reductions calculated for the three individual drive cycles
simulated in GEM: 65-mph cruise, 55-mph cruise, and a transient cycle. It also shows

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
reductions using a combination of the three GEM cycles with the cycle weightings the agencies
are assigning to represent long-haul and short-haul operation. The long-haul weighting is
calculated as 86 percent 65-mph cruise, 9 percent 55-mph cruise, and 5 percent transient. The
short-haul weighting is 64 percent 65-mph, 17 percent 55-mph, and 19 percent transient. These
percent values are based on the drive cycle weightings used in EPA's Phase 1 tractor program.178
This figure could be used to estimate the difference in performance that can be expected
when comparing a constant, 65-mph cruise test similar to SmartWay's performance tests (solid
black line) to the results from GEM (wide dashes) or to other driving conditions. These results
suggest that the SmartWay Elite target improvement of nine percent would be closer to eight
percent using GEM's long-haul simulation, while tractor-trailers that drive closer to 55-mph
would likely see improvements of 7 percent. It can also be seen that tractor-trailers driving
under highly transient conditions are likely to observe much smaller improvements. These
results are for illustrative purposes only and do not provide an exact correlation between test
results, results from GEM, and real-world results.
16%
14%
12%
10%
8%
o
3
TJ

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
performance compared to SmartWay Verified technologies (e.g., many skirts on 53-foot vans).
Additionally, short box vans (50 feet and shorter in length) are simulated with the GEM's short
haul drive cycle weightings, which results in performance that is up to two percent lower than
expected from constant 65-mph cruise speeds in the aerodynamic drag range considered in this
program.
Similar to the trend shown in Figure 2-56, even short box vans that operate in 100 percent
transient conditions experience a non-zero benefit from the use of aerodynamic devices. While
the benefit is low in these conditions, we expect a majority of short box vans, even those that
consider themselves exclusively "short-haul", will spend some time at highway speeds of 55-
mph or faster, at which time the trailer will achieve CO2 and fuel consumption reductions of at
least one percent.
Skirts+Gap
(28' dry van)
Skirts
(28' dry van}
Transient
Reduction in Aerodynmamic Drag Area, ACdA (m2)
Figure 2-57 GEM Drive Cycles' Impact on Aerodynamic Performance for a 28-Foot Box Dry Van with a
Tire Rolling Resistance Level of 5.0 kg/ton and No Weight Reduction
2.10.2.1.2 Aerodynamic Testing Results
EPA collected aerodynamic test data for many of the technologies mentioned previously
on several tractor-trailer configurations using the four test methods outlined in our test
procedures: coastdown, constant speed, wind tunnel, and CFD. The testing included multiple
tractor models, trailer models (including 53-foot, 48-foot, 33-foot, and 28-foot lengths), and
aerodynamic technologies. The results that follow are from coastdown, wind tunnel and CFD
testing. Detailed descriptions of test setup and generation of these results, including constant
speed, are provided in Chapter 3.2.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
In this rulemaking, the aerodynamic performance of a tractor-trailer vehicle is quantified
by the aerodynamic drag area, CdA (coefficient of drag multiplied by frontal area), which is a
function of both tractor and trailer aerodynamic characteristics. The following sections highlight
the impact of tractor and trailer characteristics, wind, test procedure, and trailer devices on
aerodynamic performance. These results were used to create the aerodynamic bins for trailer
manufacturers to use in compliance.
2.10.2.1.2.1 Evaluation Trailer Model Effects
The aerodynamic performance of basic trailer models does not vary significantly from
one manufacturer to the next. The wind tunnel results shown in Figure 2-58 indicate there is
very little difference in performance between trailer manufacturers for their basic trailer models.
The results shown are an average of six tractor models with each 53-foot trailer in the given
configuration. A maximum variation of 0.2 m2 is observed between trailer models with
combinations of skirts and a tail. The other configurations have variation less than 0.1 m2
These results suggest that the aerodynamic designs of current box vans do not drastically differ
by manufacturer, and the addition of bolt-on technologies is expected to result in similar
aerodynamic improvements from these base configurations.
ฆ Trailer 1 ~ Trailer 2 ~ Trailer 3
6.5
io io io
lO lO lO
5" 5.5 H II	^ o
s:: II inn inn
No Control	Skirts	Skirts+Tail
Results measured at zero yaw
Figure 2-58 Variation in Performance of Trailer Devices due to Trailer Manufacturer; Average Absolute
CdA of Six Tractors Pulling each 53-foot Basic Dry Van Model
2.10.2.1.2.2 Evaluation Tractor Model Effects
Figure 2-59 shows that there is more variation in aerodynamic performance when
considering tractor models. All of the tractors shown in the figure are Class 8 high roof sleeper
cabs with similar aerodynamic features, but from four separate manufacturers. The absolute
CdA ranges from 0.2 m2 to 0.3 m2 depending on trailer configuration.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
i Tractor 4 ~ Tractor 8 ~ Tractor 9 ~ Tractor 11
CM
E
6.5
6.0
5.5
r-
to LO
ซ ui
CD
T3 5.0
O
4.5
4.0
O IT)
lO
CM
o iri
LO
I
No Control
Skirts	Skirts+Tail
Results measured at zero yaw
Figure 2-59 Variation in Aerodynamic Performance of Trailer Devices due to Tractor Manufacturer;
Average Absolute CdA of Three 53-Foot Dry Vans Pulled by each Tractor Model
By subtracting the absolute CdA value of the "Skirts" and "Skirts+Tail" configurations
from their corresponding "No Control" configuration, we obtain a change in CdA (i.e., "delta
CdA") that gives the relative impact of adding devices compared to a no control trailer.
Considering a delta CdA instead of absolute values reduces some of the impact of the tractor
characteristics and consequently reduces the variation by nearly half. Figure 2-60 shows that the
variation observed between tractor models is 0.15 m2 or less when using delta CdA. This
reduction in variation due to vehicle characteristics is one of the reasons the agencies are
choosing a delta CdA approach for the Phase 2 trailer program's aerodynamic testing. The
aerodynamic performance results in the rest of this section will be presented as delta CdA.
i Tractor 4 ~ Tractor 8 ~ Tractor 9 ~ Tractor 11

1.8

1.6

1.4
cn"
1.2
E
1.0
<
0.8
~o

O
0.6
ra
-i—*
0.4

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.10.2.1.2.3 Evaluation of Yaw Effects
As discussed in Chapter 2.8, the tractor program, which is using wind-averaged drag
results, specifies the coastdown test procedures as a reference test method and manufacturers
apply a correction factor to "alternative methods" (i.e., wind tunnel, CFD, or constant speed) in
order to maintain consistency between methods. The trailer program did not propose to require a
reference test, in order to reduce the test burden for manufacturers and allow them to choose an
appropriate test method for their needs and resources. The agencies also proposed standards that
were developed using zero yaw drag results. The agencies recognize that the benefits of
aerodynamic devices for trailers can be better seen when measured considering multiple yaw
angles, but we did not propose to accept wind-averaged drag results. The coastdown procedure
has near-zero wind restrictions and we were concerned that devices that show larger benefits at
greater yaw angles would not be captured in coastdown testing.
Commenters indicated that it was unlikely they would use coastdown testing for
compliance. Instead, they would rely on wind tunnel and CFD. Additional commenters
suggested that we consider wind-averaged results for the trailer program and, accordingly, we
evaluated the coastdown and wind tunnel results again, including new results from tests that
were completed following publication of the NPRM.
To evaluate the effect of wind, we compared the zero yaw and wind-averaged results
from EPA's wind tunnel tests. All wind-average results in this section are calculated from a
fourth-order polynomial fit to the measured yaw curve. As described in Chapter 3, the agencies
found that the average of the results from the equation at positive and negative 4.5 degrees yaw
angles was consistent with the wind-averaged results at 7 degrees and 65 miles per hour vehicle
speed (see Chapter 3.2 of this RIA, and 40 CFR 1037.810).
The results shown in Figure 2-61 compare the delta CdA at zero yaw with the wind-
averaged values for tests of six different tractors pulling three different models of 53-foot dry
vans. Figure 2-62 shows a similar comparison for two sets of tractor-trailers with solo 28-foot
dry vans. The wind-averaged analysis generally results in a narrower range of performance for a
given technology. The gap reducer technology shows minimal benefit under a zero yaw analysis
for the 53-foot vans, but a measurable benefit when yaw angles are considered. Tails also show
a noticeable improvement under yaw conditions. The short van results show larger increases in
delta CdA when wind-averaged results are considered.

-------
' E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review
1.80
1.60
Compare Technology Effectiveness: Zero Yaw & Wind-Averaged Delta CdA
From Wind Tunnel Testing of 53-Foot Dry Vans
Open = Zero Yaw
Solid = Wind-Averaged
1.40
ฃ 1.20
<
O 1.00
o>
Q 0.80
0.60
0.40
0.20
0.00
3
oo
e i
Ql
Gap
X
X
o
!!
+
o
DTail < Skirts SSkirts+Gap E:Skirts+Tail
Skirts+Tail+Gap
Figure 2-61 Comparison of Zero Yaw and Wind-Averaged Delta CdA for Wind Tunnel Tests of 53-Foot Dry
Vans; Results from Seven Class 8 Sleeper Cab Tractors and Three Dry Van Models
E
<
TJ
o
0)
Q
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
Technology Effectiveness: Zero Yaw & Wind-Averaged Delta CdA
From Wind Tunnel Testing of 28-Foot Dry Vans
Open = Zero Yaw
Solid = Wind-Averaged
0
OO
CGap DTail
*
y*
63
X
X
Si
+
+
o Skirts Skirts+Gap xSkirts+Tail + Skirts+Tail+Gap
Figure 2-62 Comparison of Zero Yaw and Wind-Averaged Delta CdA for Wind Tunnel Tests of 28-Foot Dry
Vans; Results from Two Class 7 Day Cab Tractors and Two Dry Van Models

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
In light of trailer manufacturers' preference for wind tunnel and CFD, and the benefit
observed when testing at higher yaw angles, we are adopting standards based on wind-averaged
delta CdA values. The following section describes the variation seen in our testing of the three
test methods, including a comparison of the wind-averaged wind tunnel and CFD results to the
coastdown values at near-zero yaw angles.
2.10.2.1.2.4 Evaluation of Test Procedure Effects
As mentioned previously, EPA evaluated trailer aerodynamic performance using three
test procedures: coastdown, wind tunnel and CFD. EPA performed its wind tunnel testing at
ARC Indy using a l/8th-scale model of several tractor-trailers. We also obtained data from
National Research Council of Canada (NRC) from a 30 percent scale model in their 9-meter
wind tunnel.179 Figure 2-63 compares the coastdown and two wind tunnel facilities. The tractor
and trailer used in the coastdown and two wind tunnels are similar, but are not exact matches in
these tests and we cannot directly compare the numerical results. The coastdown tractor
corresponds to Tractor #3 in the coastdown results of Chapter 3.2 and the ARC wind tunnel
model corresponds to Tractor #5 in the ARC wind tunnel results.180 The NRC model is a generic
tractor developed by NRC. The comparison of trailers with skirts suggest that the coastdown and
wind tunnel methods produce similar results with these devices, and the effect of accounting for
higher yaw does not improve the performance with these devices. The limited yaw effect with
skirts was also observed in Figure 2. The yaw impact does appear to be larger when a tail is
included in the trailer configuration. The two wind tunnel results are within 0.2 m2, but the
coastdown result is much lower than both wind tunnel values.
ฆ Coastdown nWind Tunnel, 1/8th Scale nWind Tunnel, 30% Scale
1.8
1.6
1.4
I1-2	n
< 1.0
Q
O 0.8
I
Q 0-4 I — H
I I
0.0	1
Skirt	Skirt + Tail
Figure 2-63 Comparison of Coastdown and Wind Tunnel Test Methods using Similar Tractor-Trailers with
a 53-Foot Dry Van
We also compared CFD results from two separate CFD packages. One is based on
Reynolds Averaged Navier-Stokes and the other is Lattice-Boltzmann-based. The two packages
were tested using the same tractor-trailer model, though there were some differences in grid
generation techniques, and open-road environments with a Reynolds number of 1. Ie6. Figure

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
2-64 compares coastdown and wind tunnel results to those predicted by the CFD models. The
coastdown tractor corresponds to Tractor #1 in the coastdown results of Chapter 3.2 and the wind
tunnel tractor corresponds to Tractor #11 in the ARC wind tunnel results.181 The results show
some difference between the CFD packages in the skirt configuration, but the differences remain
within 0.2 m2 between all methods shown. Similar to zero yaw results in Figure 2-61, the
coastdown results are much lower for the configuration with the tail, and we believe this is more
of a yaw effect than a variability between methods.
ฆ Coastdown nWind Tunnel, 1/8th Scale nRANSCFD nL-BCFD
1.8
1.6
ST1-4	_
—12	I	II	
ง1-0	ฆ
I- ฐ'8 	 I
I	II
n fel
™	-L-
Skirt	Skirt + Tail
Figure 2-64 Comparison of Coastdown, Wind Tunnel and CFD Test Methods using Similar Tractor-Trailers
with a 53-Foot Dry Van
In general, Figure 2-63 and Figure 2-64 show that the test methods are reasonably close
for a given tractor-trailer configuration. We believe the lower values from the coastdown tests in
configurations that include tails are likely due to the relatively low yaw angles of that test
method, which was also seen in Figure 2-61 for 53-foot dry vans when comparing the zero yaw
and wind-averaged results of tail configurations.
Figure 2-65 displays all of the aerodynamic test results for used in our analysis of 53-foot
dry vans for the given configurations. Each data point is an individual test and the markers differ
based on test method. You can see that the three test methods (which include two wind tunnel
facilities and two CFD packages) produce similar results for most trailer configurations. With
the exception of the one coastdown data point for the tail configuration, even the coastdown
results at near-zero yaw are grouped relatively close to the results from the other test procedures.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Compare Technology Effectiveness: Wind-Averaged Delta CdA
From Several Test Methods of 53-Foot Dry Vans
ni/8th-Scale Wind Tunnel O30%-Scale Wind Tunnel ACoastdown RANS CFD xL-B CFD
1.80
1.60
1.40
ฃ 1.20
<
o 1.00
to
9
O 0.80
0.60
0.40
0.20
0.00
Figure 2-65 Technology Effectiveness for Several Devices on 53-Foot Dry Vans using Three Test Methods,
Including Two Wind Tunnel Facilities and Two CFD Packages
2.10.2.1.2.5 Evaluation of Aerodynamic Device Performance
Bolt-on aerodynamic technologies can be used individually or in combination. This
section summarizes our comparison of the performance of devices that were tested individually
and in combination with other devices. EPA evaluated several combinations in its aerodynamic
testing and those results are shown below.
Figure 2-66 shows the performance of three bolt-on devices when installed on three
different l/8th-scale trailer models in the wind tunnel. Each trailer is pulled by the same tractor
(i.e., Tractor #4 from the ARC wind tunnel data). These three devices are often used in
combination and it was of interest to investigate if the performance of these devices was additive
when combined, or if the devices work synergistically to achieve greater reductions in
combination.



















-
ปQK








=
A

:
~







A




~
~ A





ฃ
~







-
g	































B
A




Gap	Tail	Skirts Skirts+Gap Skirts+Tail Skirts*
Tail+Gap

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
i Trailer 1 ~ Trailer 2 ~ Trailer 3
1.8
1.6
IN 14
ฃ1.2
< 1.0
o
ns
d>
Q
0.8
0.6
0.4
0.2
0.0
S ฐ H
S ฐ ฐ
CO CO (N
q o o
o o o
I
Gap
Tail
Skirts
Figure 2-66 Wind Tunnel Performance of Individual Bolt-On Trailer Devices; Tractor #4 (ARC Wind
Tunnel Data) Pulling Each Trailer
In comparison to the values shown in Figure 2-66, Figure 2-67 shows that the devices are
more effective when combined, compared to the sum of their individual performances. For
example, the sum of the individual performances of the tail and skirts on Trailer #1 is 0.98 m2
and the sum of all three device performances is 1.02 m2 Yet, when tested in combination, they
achieve 1.13 m2 and 1.17 m2, respectively. Trailer #3 has similar levels of improvement for the
combined devices (about 13 percent compared to the sum of the individual performances).
However, the improvement from Trailer #2 is only about four percent. While these results
suggest there may be synergies between these particular device combinations, we would not be
able to predict a consistent improvement across all tractor and trailer models.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
i Trailer 1 ~ Trailer 2 ~ Trailer 3
1.8
1.6
— 1.4

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
different lengths, and concludes with a comparison of solo and tandem configurations. The
agencies are including these results to give a general idea of the relative performance that could
be expected when trailers of different lengths or configurations are used. Manufacturers will
continue to use data from solo 28-foot and 53-foot trailer testing for compliance.
Figure 2-68 compares the performance of four dry van lengths. The day cab (DC) tractor
is the same for the 28-foot, 48-foot, and 53-foot trailers shown. The 33-foot van was modeled
with a MY 2014 sleeper cab in a separate test set. We are including the 33-foot results in the
plot for qualitative assessment. You can see that the individual devices do not show a consistent
trend in performance based on trailer length, but there is a noticeable trend of increased
performance with increased length for combinations of devices.
1.80
1.60
1.40
_ 1.20
ฃ_
ง 1.00
o
ซ 0.80
0.60
0.40
0.20
0.00
Technology Effectiveness: Wind-Averaged Delta CdA
From Wind Tunnel Testing Performed on Several Van Lengths




























a




CL


0
+




ro
O









ฃ


+
r
CO



CT3
a


+






+


r




a


Skirts
Y—
+

j*:
CO
s
e
JC
CO















Q.
O

TO
O r=-|

a.

Q-
(O





O

O

28-ft 2012 DC
33-ft 2014 SC
48-ft 2012 DC
53-ft 2012 DC
Figure 2-68 Comparison of Aerodynamic Performance of Devices on Several Dry Van Lengths; 2012 DC is a
6x4 Day Cab Tractor, and 2014 SC is a 6x4 Sleeper Cab
It should be noted that the 53-foot van is the only "long box van" in this set of trailers.
The 28-foot, 33-foot, and 48-foot trailers are considered "short box vans" in this trailer program
and are represented by a 28-foot trailer for compliance. These results suggest that the shorter
surrogate test trailer will underestimate performance for the longer trailers in its regulatory
subcategory, providing a conservative measure of potential benefits when the longer trailers are
in use.
EPA also tested the 28-foot and 33-foot van in a tandem configuration. Each van pair
was tested with skirts on the first trailer only, skirts on the second trailer only, skirts on both
trailers, skirts and a gap reducer on both trailers, and skirts and a gap reducers on both trailers

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review **
with a tail on the second trailer. As shown in Figure 2-69, the skirts perform similarly for a
given length van when they are on an individual van only, but provide almost twice the benefit
when installed on both vans. The addition of the tail further improves the performance of the
pair of trailers.
Technology Effectiveness: Wind-Averaged Delta CdA
From Wind Tunnel Testing Performed on Tandem Dry Vans

1.80

1.60

1.40
(X
1.20 --
E


-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review *
these results suggest that there is an added performance benefit if customers were to purchase
and deploy a tail on vans that may be used in tandem.
Technology Effectiveness: Wind-Averaged Delta CdA
From Wind Tunnel Testing Performed on Solo & Tandem Dry Vans
1.80
28-ft 6x4 DC
28-ft 6x4 DC, Tandem
33-ft SC
33-ft SC, Tandem
Figure 2-70 Comparison of Aerodynamic Device Performance on Solo and Tandem Dry Vans; the 28-foot
Van is Pulled by a 6x4 Day Cab Tractor, and the 33-foot Van is Pulled by as a Sleeper Cab Tractor
2.10.2.1.3 Performance Bins for Aerodynamic Technologies
The agencies developed aerodynamic bins based on delta CdA to encompass technologies
that are expected to provide similar improvements in drag, and which are intended to account for
variability due to tractor model, test method, device manufacturer, and trailer manufacturer. The
proposed bins were based on zero yaw test results. For the final rulemaking, we are adopting
standards based on wind-averaged aerodynamic test data, for reasons explained immediately
below. In addition, we completed several test programs after the NPRM. The bins described
here reflect the new test results, and our use of wind-averaged values.
Figure 2-71 overlays the aerodynamic bins that we proposed in the NPRM on our recent
wind-averaged test results. While some of the technologies fit into those bins, many of the same
technologies overlap two or more bins. In addition, when the results are wind-averaged, tails and
skirts have similar performance, suggesting that they should be in the same bin.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***

1.80

1.60

1.40
CN
E
1.20
<

u
1.00
(U
ฆ*->

O

a
0.80

0.60

0.40

0.20

0.00
Compare Technology Effectiveness: Wind-Averaged Delta CdA
From Several Test Methods of 53-Foot Dry Vans
ni/8th-Scale Wind Tunnel ซ>30%-Scale Wind Tunnel ACoastdown RANS CFD XL-B CFD
NPRM Bin VIII = 18












I—, NPR
W Bin VII = 1.4





B











A

u
~
NPF
M Bin VI = 1.0





J
i





~
u




tT)
~

NP
iM Bin V= 0.7


n









J




NPF
M Bin IV = 0.5


_
3?













NPF
!M Bin III =0.3







	




NP
?M Bin II =0.1
	






Gap	Tail	Skirts Skirts+Gap Skirts+Tail Skirts-*-
Tail+Gap
Figure 2-71 Wind-Averaged Trailer Aerodynamic Test Results Relative to the NPRM Bins
We adjusted the aerodynamic bins to reflect the additional data and the use of wind-
averaged results, as seen in Figure 2-72. The most notable difference is that we expanded the
lower bins. The Bin II threshold delta CdA remains 0.1 m2 Anything below that threshold is
assigned a value of zero. The NPRM Bins III, IV and V were reduced to two bins, such that
Bins II, III and IV are each a width of 0.3 m2 Technologies that achieve a threshold value of 0.4
m2 or greater, such as most of the skirts and tails tested, are assigned to Bin III. Bin IV, which
has a threshold of 0.7 m2, includes the configurations tested with skirts and gap reducers, and
some of the lower performing skirt and tail combinations. A majority of the skirts and tail
combinations and skirts, tails and gap reducer combinations are in Bin V, which is assigned a
value of 1.0 m2 These combinations represent the highest performing devices that we tested.
Bins V, VI, and VII are identical to the highest bins from the NPRM. The agencies observed one
device combination that presently meets Bin VI, suggesting that this bin can be met with
combinations of existing aerodynamic technologies. The agencies believe that there is ample
lead time to optimize additional existing Bin V combinations such that they can also meet Bin VI
by MY 2027.

-------
1.80
1.60
1.40
ฃ 1.20
<
o 1.00
(U
9
Q 0.80
0.60
0.40
0.20
r E. O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review
Compare Technology Effectiveness: Wind-Averaged Delta CdA
From Several Test Methods of 53-Foot Dry Vans
ni/8th-Scale Wind Tunnel <0>3O%-Scale Wind Tunnel ACoastdown RANS CFD XL-B CFD
Bin VII = 1.8













BinVI = 1.4





B











A

u
~

Bin V = 1.0





J






~
u
A




A	
ฃT)
~


Bin IV = 0.7




—
A "*ฆ






p

-






$

-I




Bin III = 0 4



Zi




	





Bin II =0.1
—






Gap	Tail	Skirts Skirts+Gap Skirts+Tail Skirts*
Tail+Gap
Figure 2-72 Wind-Averaged 53-Foot Dry Van Aerodynamic Test Results Relative to the Aerodynamic Bins
that will be Used for Compliance
Much of our testing focused on 53-foot trailers, but we did test several combinations of
solo 28-foot trailers that will be used to represent all short box vans in compliance testing.
Figure 2-73 shows the wind-averaged results for two 28-foot dry vans in several configurations
from wind tunnel and coastdown testing. Similar to the 53-foot dry van results, the performance
of tails and skirts fit into the same bin. It is interesting to note that these results suggest a 28-foot
dry van with skirts and a gap reducer have similar performance as a skirts and tail combination.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
Compare Technology Effectiveness: Wind-Averaged Delta CdA
From Wind Tunnel and Coastdown on 28-Foot Dry Vans
~ Wind Tunnel oCoastdown
Bin VII = 1.8




















Bin VI = 1.4



























Bin V = 1.0




















Bin IV = 0.7





~




~
~
~




ฆ
n

Bin III =0.4


u
ฅ










o
n




Bin II = 0 1
u






Gap	Tail	Skirts Skirts+Gap Skirts+Tail Skirts*
Tail+Gap
Figure 2-73 Wind-Averaged 28-Foot Dry Van Aerodynamic Test Results Relative to the Aerodynamic Bins
that will be Used for Compliance
While the agencies have chosen to test and regulate 28-foot box vans individually, they
are often pulled in a tandem configuration, which restricts the types of aerodynamic devices that
can be applied on the rear of the trailers. We expect rear devices such as boat tails would not be
practical for 28-foot box vans, since those devices are only deployable when the trailer is in the
rear position. We did not base our standards on the use of rear devices. However, the short box
van subcategories include other trailer lengths (e.g., 40-foot and 48-foot) that would be able to
use rear aerodynamic devices and we do not restrict the use of those devices as a means of
achieving compliance. We presented results from 28-foot configurations that included tails to
demonstrate the level of performance that can be expected when operating with those devices.
Table 2-95 below summarizes the bin structure that the agencies will use as the basis for
compliance. Also included in the table are example aerodynamic packages that the agencies
used for our cost analysis summarized below in Chapter 2.10.4.3 and fully described in in
Chapters 2.11 and 2.12. Note that the same technologies are assumed to work for dry and
refrigerated vans in each length category. We assume manufacturers that wish to achieve bins
where our example packages include gap reducers can have a different, similarly effective
technology installed in a separate location on refrigerated vans without additional cost. In each
set of example technologies, we present packages for bin performance that were not observed in
our testing. We considered these packages to be "Optimized Combinations" and assume their

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
cost to be that of an appropriately sized skirt, tail and gap reducer. The highest bins in each
category is assumed to require changes to the design of the trailer, and we did not estimate a cost
for those bins.
Table 2-95 Aerodynamic Technology Bins used to Evaluate Trailer Benefits and Costs
BIN
DELTA CDA
EXAMPLE TECHNOLOGY PACKAGES
Measured
GEM Input
Value
Long Vans
Short Vans
Bin I
<0.10
0.0
No Aero Devices
No Aero Devices
Bin II
0.10-0.39
0.1
High Performing Gap Reducer
Skirts or Tail
Bin III
0.40-0.69
0.4
Skirts or Tail
Skirts + Gap Reducer
Bin IV
0.70-0.99
0.7
Skirts + Gap Reducer
Optimized Combinations
Bin V
1.00 - 1.39
1.0
Skirts + Tail
Changes to Trailer Design
Bin VI
1.39 - 1.79
1.4
Optimized Combinations

Bin VII
> 1.80
1.8
Changes to Trailer Design

The agencies used EPA's Greenhouse gas Emissions Model (GEM) vehicle simulation
tool to conduct this analysis. Within GEM, the aerodynamic performance of each trailer
subcategory is evaluated by subtracting the delta CdA shown in Table 2-95 from the CdA value
representing a specific standard tractor pulling a trailer with no CO2- or fuel consumption-
reducing technologies (i.e., a "no-control" trailer). EPA's aerodynamic testing of Class 8 high
roof sleeper cab tractors pulling standard 53-foot dry vans in its no-control baseline
configuration (zero aerodynamic trailer technologies) produced an average CdA value of 5.9 m2
in coastdown testing and an average wind-averaged CdA from wind tunnel tests was 6.0 m2 The
average CdA value for the solo 28-foot dry van in its no-control configuration was 5.3 m2 for
coastdown and the average CdA from wind tunnel results were 5.6 m2 when wind-averaged.
The agencies chose to model the no-control long dry van subcategory using a default
CdA value of 6.0 m2 (the mean wind-averaged CdA from EPA's wind tunnel testing) in GEM.
We also chose the wind tunnel result of 5.6 m2 to represent the short dry van subcategory. The
agencies did not test any refrigerated vans, but we assumed a refrigerated van's TRU would
behave similar to a gap reducer. Our test results did not show gap reducer technologies to have a
significant effect on CdA and the agencies assigned the same default CdA to refrigerated and dry
box vans in GEM. The trailer subcategories that have design standards (i.e., non-box and non-
aero box trailers) do not have numerical standards to meet, and thus do not have defaults in
GEM. Table 2-96 illustrates the no-control drag areas (CdA) associated with each trailer
subcategory.
Table 2-96 Default CdA Values Associated with the No Control Trailer Configuration within GEM
TRAILER
DRY VAN
SUBCATEGORY

Long Dry Van
6.0
Short Dry Van
5.6
Long Ref. Van
6.0
Short Ref. Van
5.6

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.10.2.2 Tire Rolling Resistance
2.10.2.2.1	Lower Rolling Resistance Tires
On a typical Class 8 long-haul tractor-trailer, over 40 percent of the total energy loss from
tires is attributed to rolling resistance from the trailer tires.182 Trailer tire rolling resistance
values were collected by the agencies to use in the GEM-simulated tractor-trailer vehicle for
Phase 1. The agencies found that the average coefficient of rolling resistance (CRR) for new
trailer tires at that time was 6.0 kg/ton. This value was applied in GEM for the standard trailer
used for tractor compliance in the Phase 1 tractor program. For Phase 2, the agencies are
adopting the same baseline CRR for trailer tires and consider all box van tires with CRR values
below 6.0 kg/ton to be "lower rolling resistance" (LRR) tires. For reference, a trailer tire that
qualifies as a SmartWay-verified tire must meet a CRR value of 5.1 kg/ton, a 15 percent CRR
reduction from the trailer tire identified in Phase 1. Our research of rolling resistance indicates
an additional CRR reduction of 15 percent or more from the SmartWay verification threshold is
possible with tires that are available in the commercial market today.
Similar to the case of tractor tires, LRR tires are available as either dual or as single wide-
based tires for trailers. Single wide-based tires achieve CRR values that are similar to their dual
counterparts, but have an added benefit of weight reduction, which can be an attractive option for
trailers that frequently maximize cargo weight.
2.10.2.2.2	Performance Levels for LRR Tires
Similar to the Phase 2 tractor and vocational vehicle programs, the trailer program is
based on performance reflecting adoption of lower rolling resistance tires (or, for the non-aero
subcategories, actually adopting such tires). Feedback from several box trailer manufacturers
indicates that the standard tires offered on their new trailers are SmartWay-verified tires (i.e.,
CRR of 5.1 kg/ton or better). An informal survey of members from the Truck Trailer
Manufacturers Association (TTMA) indicates about 85 percent of box vans sold today have
SmartWay tires.183 While some trailers continue to be sold with tires of higher rolling
resistances, the agencies believe most box trailer tires currently achieve the baseline trailer tire
CRR of 6.0 kg/ton or better.
The agencies evaluated two levels of box van tire performance for these rules beyond the
baseline trailer tire with a CRR of 6.0 kg/ton. The first performance level was set at the criteria
for SmartWay-verification for trailer tires, 5.1 kg/ton, which is a 15 percent reduction in CRR
from the baseline. As mentioned previously, several tire models available today achieve rolling
resistance values well below the present SmartWay threshold. The agencies expect that tire
manufacturers will continue to respond to demand for more efficient tires and will offer
increasing numbers of tire models with rolling resistance values significantly better than today's
typical LRR tires. We believe it is reasonable to expect the trailer industry could adopt tires with
rolling resistances at a second performance level early in the program. The agencies prosed
standards based on meeting an additional eight percent reduction in rolling resistance by MY
2024, but, given that such a high fraction of new box vans are already adopting LRR tires, we are
adopting standards based on a CRR performance of 4.7 kg/ton by MY 2021. The agencies

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
evaluated these three tire rolling resistance levels, summarized in Table 2-97, in the feasibility
analysis of the following sections.
We received comment from Michelin supporting the use of 6.0 kg/ton as the box van tire
rolling resistance baseline, but they expressed concern that the SmartWay threshold of 5.1 kg/ton
does not apply for non-box trailers, and could compromise their operation. In addition, the
Rubber Manufacturers Association indicated that a baseline of 6.0 kg/ton does not apply to non-
box trailers. The agencies agree that the baseline tires for non-box trailers should have a higher
roller resistance, but we did not receive any comments that included Crr data. For the analysis
for the final rules, the agencies used 2014 tire rolling resistance information submitted by tractor
and vocational manufacturers for Phase 1 compliance to establish a revised baseline Crr value of
6.5 kg/ton for non-box trailer manufacturer. Table 2-97 summarizes the rolling resistance levels
we evaluated in the Phase 2 trailer program.
Table 2-97 Summary of Trailer Tire Rolling Resistance Levels Evaluated
ROLLING
RESISTANCE LEVEL
CRR (KG/TON)
Level 1 (Non-Box Baseline)
6.5
Level 2 (Box Van Baseline)
6.0
Level 3
5.1
Level 4
4.7
2.10.2.3 Tire Pressure Systems
The inflation pressure of tires also impacts the rolling resistance. Tractor-trailers
operating with all tires under-inflated by 10 psi have been shown to increase fuel consumed by
up to one percent.184 Tires can gradually lose pressure from small punctures, leaky valves or
simply diffusion through the tire casing. Changes in ambient temperature can also affect tire
pressure. Trailers that remain unused for long periods of time between hauls may experience any
of these conditions. A 2003 FMCSA report found that nearly one in five trailers had at least one
tire under-inflated by 20 psi or more. If drivers or fleets are not diligent about checking and
attending to under-inflated tires, the trailer may have much higher rolling resistance and much
higher CO2 emissions and fuel consumption.
2.10.2.3.1 Types of Tire Pressure Systems
Tire pressure monitoring systems (TPMS) and automatic tire inflation systems (ATIS)
are designed to address under-inflated tires. Both systems alert drivers if a tire's pressure drops
below its set point. TPMS simply monitors the tires and require user-interaction to reinflate to
the appropriate pressure. Today's ATIS take advantage of trailers' air brake systems to supply
air back into the tires (continuously or on demand) until a selected pressure is achieved. In the
event of a slow leak, ATIS have the added benefit of maintaining enough pressure to allow the
driver to get to a safe stopping area.185 As described in Chapter 2.4.3.3, the agencies will
recognize both systems in the Phase 2 trailer program.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.10.2.3.2 Performance of Tire Pressure Systems
Estimates of the benefits of tire pressure systems vary depending on the base level of
maintenance already performed by the driver or fleet, as well as the number of miles the trailer
travels. Trailers that are well maintained or that travel fewer miles would experience less
benefits from these systems compared to trailers that often drive with poorly inflated tires or log
many miles. The agencies believe these systems can provide a CO2 and fuel consumption
benefit to most trailers. With ATIS use, trailers that have lower annual vehicle miles traveled
(VMT) due to long periods between uses would be less susceptible to low tire pressures when
they resume activity. Trailers with high annual VMT or frequent changes in ambient conditions
would experience the fuel savings associated with consistent tire pressures. TPM systems would
provide a warning of inappropriate tire pressure and the agencies believe the operators have
sufficient incentive to correct the pressure as soon as possible. Tire inflation systems could
provide a CO2 and fuel consumption savings of 0.5-2.0 percent, depending on the degree of
under-inflation in the trailer system.
Maintaining tire pressure is important to fuel consumption. Tire manufacturers estimate
a tire pressure 10 psi below target results in a 0.9 percent increase in fuel consumption. Two
studies have evaluated truck and trailer tire inflation including FMCSA (2003) and TMC
(2002). 186>187 In the 2003 FMCSA study, tire inflation (psi) was measured in 3,200 tractors and
1,300 trailers. The TMC study measured tire inflation rates in two fleets and found that only 38
percent of sampled trailer tires were within +/- 5 psi of target pressure as prescribed by tire
manufacturers. The study also found that more than 20 percent of tires were 20 psi or more
underinflated and four percent of tires were 50 psi or more underinflated compared to the
target. The FMCSA study found similar results. These figures suggest under inflation of tractor
and trailer tires in the U.S. fleet could result in an increase in fuel consumption of approximately
one to two percent. Most recently, FMCSA (2014) evaluated trailer ATIS on trailers in two test
fleets.188 The study found ATIS on trailers, in conjunction with TPMS use on tractors, improved
fuel consumption 1.4 percent in test trucks as compared to control trucks in those fleets.
NHTSA and EPA recognize the role of proper tire inflation in maintaining optimum tire
rolling resistance during normal trailer operation. For these rules, rather than require
performance testing of tire pressure systems, the agencies will recognize the with a single default
reduction for manufacturers that incorporate ATIS or TPMS into their trailer designs. Based on
information available today, we believe that there is a narrow range of performance among
technologies available and among systems in typical use. We proposed to assign a 1.5 percent
reduction in CO2 and fuel consumption for all trailers that implement ATIS, and no credit for
TPMS due to their inherent dependence on operator interaction.189 Based on comments, we are
assigning a 1.2 percent reduction for ATIS and a 1.0 for TPMS. The discounted TPMS value is
meant to reflect our acceptance that a notification will incentivize an operator to address the
problem, but we cannot ensure that it will be done. We believe the use of these systems can
improve tire pressure maintenance and reduce tire rolling resistance.
2.10.2.4 Weight Reduction
Reduction in trailer tare (or empty) weight can lead to fuel consumption reductions in two
ways. For applications where payload is not limited by weight restrictions, the overall weight of

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
the tractor and trailer would be reduced and would lead to improved fuel efficiency. For
applications where payload is limited by weight restrictions, the lower trailer weight would allow
additional payload to be transported during the truck's trip, so g/ton-mile emissions would
decrease. Weight reduction opportunities in trailers exist in both the structural components and
in the wheels and tires. Manufacturers commonly replace components such as roof posts, bows,
side posts, cross members, floor joists, and floor sections with lighter weight options.
Major lower-weight options are not offered consistently by all trailer manufacturers
across the industry. For example, some manufacturers have already marketed lower-weight
major components for many years, while others to date have not done so. There is no clear
"baseline" for current trailer weight against which lower-weight designs could be compared for
regulatory purposes. Trailer manufacturers do not generally sell a single model. Instead, each
sale is likely to include customer-specified configurations with application-specific components.
For this reason, the agencies do not believe it would be appropriate or fair across the industry to
identify a single trailer as a standard baseline from which to apply overall weight reductions
toward compliance. However, the agencies do believe it would be appropriate to allow a
manufacturer to account for weight reductions that involve substituting very specific,
traditionally heavier components with lower-weight options that are not currently widely adopted
in the industry. This method allows manufacturers to easily identify and install components that
will improve benefit them in compliance.
The agencies recognize that when weight reduction is applied to a trailer, some operators
will replace that saved weight with additional payload. To account for this in the average trailer
represented in the GEM vehicle simulation tool, it is assumed that one-third of the weight
reduction is applied to the payload. For tractor-trailers simulated in GEM, it takes a weight
reduction of nearly 1,000 pounds before a one percent fuel savings is achieved and about a 2,500
pound reduction to reach three percent savings. The component substitutions identified by the
agencies result in weight reductions of less than 500 pounds, yet can cost over $1,000. The
agencies believe that few trailer manufacturers would apply weight reduction solely as a means
of achieving reduced fuel consumption and CO2 emissions, and the standards that can be met
without reducing weight. However, we will offer weight reduction as an option for box trailer
manufacturers who wish to apply it to some of their trailers as part of their compliance strategy.
2.10.2.4.1 Weight Reduction Options Recognized in these Rules
For these rules, the agencies have identified several conventional components with
available lighter-weight substitutes (e.g., substituting conventional dual tires with steel wheels
with single wide-based tires and aluminum wheels). We are adopting values for the associated
weight-related savings that would be applied with these substitutions for compliance. We
believe that the initial cost of these component substitutions is currently substantial enough that
only a relatively small segment of the industry has adopted these technologies today.
In addition to weight reduction associated with replacing standard steel wheels with
aluminum versions, and adopting single wide-based tires in place of dual tires, the agencies have
identified 11 common trailer components that have lighter weight options available.I90-191-192-193
Some of the references include confidential data that outlined weight savings and costs
associated with these material substitutions. Table 2-98 lists the components, and estimates of

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
weight savings and costs obtained by the agencies. The table includes one update to the weight
reduction value assigned to floor cross-members. The Aluminum Association indicated that this
value should be 250 pounds and we adjusted the table accordingly.
Manufacturers that adopt these technologies would sum the associated weight reductions
and apply those values in GEM. Steel wheels can be replaced with aluminum wheels and two
dual tires can be replaced with single wide-based tires on aluminum wheels. Relatively large
weight savings are possible by replacing steel upper coupler assemblies or suspension sub-
frames with aluminum versions, but these substitutions are more expensive and more labor-
intensive to install.
Table 2-98 Weight Reduction Options for Trailers
COMPONENT
MATERIAL
WEIGHT

SUBSTITUTION
REDUCTION (LB)
Hub and Drum (per axle)
Cast Iron to Aluminum
80
Floor
Hardwood to Aluminum
375
Floor
Hardwood to Composite
245
Floor Crossmembers
Steel to Aluminum
250
Landing Gear
Steel to Aluminum
50
Rear Door
Steel to Aluminum
187
Rear Door Surround
Steel to Aluminum
150
Roof Bows
Steel to Aluminum
100
Side Posts
Steel to Aluminum
300
Slider Box
Steel to Aluminum
150
Structure for Suspension Assembly
Steel to Aluminum
280
Upper Coupler Assembly
Steel to Aluminum
430
In addition to these conventional components, manufacturers have the option to evaluate
their own trailer weight reduction through the off-cycle testing provisions outlined in the
regulations. Manufacturers can seek approval of a baseline trailer from their own recent
production, and compare its weight to a new, lighter-weight model through an "A to B" weight
measurement. The difference between these two trailers can be applied in GEM for a weight
reduction value.
2.10.2.5 Effectiveness of Technologies
The final standards for trailers are predicated on four performance parameters:
aerodynamic drag reduction, tire rolling resistance reduction, and the adoption of tire pressure
systems and weight reduction. Table 2-99 summarizes the performance levels for each of these
parameters based on the technology characteristics outlined in Chapter 2.10.2.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-99 Performance Parameters for the Trailer Program
AERODYNAMICS (DELTA CDA, M2)
Bin I
0.0
Bin II
0.1
Bin III
0.4
Bin IV
0.7
Bin V
1.0
Bin VI
1.4
Bin VII
1.8
Tire Rolling Resistance (CRR, kg/ton)
Level 1 (Non-Box Baseline)
6.5
Level 2 (Box Van Baseline)
6.0
Level 3
5.1
Level 4
4.7
Tire Inflation System (% reduction)
ATIS
1.2
TPMS
1.0
Weight Reduction (pounds)
Weight
1/3 added to payload,

remaining reduces overall

vehicle weight
As part of the process of demonstrating compliance, trailer manufacturers will perform an
aerodynamic test and measure a delta CdA. The delta CdA value will determine which Bin value
the manufacturer will supply to GEM (i.e. the GEM equation) for compliance. While
manufacturers are required to use the exact value assigned to the aerodynamic bins, they are free
to use any tire rolling resistance value obtained from tire testing.
These performance parameters have different effects on each trailer subcategory due to
differences in the simulated trailer characteristics. Table 2-100 shows the agencies' estimates of
the effectiveness of each parameter for four box trailer types. Each technology was evaluated in
GEM using the baseline parameter values for the other technology categories. For example, each
aerodynamic bin was evaluated using the Tire Level 1 (6.0 kg/ton) and the Base weight reduction
option (zero pounds). The table shows that aerodynamic improvements offer the largest
potential for CO2 emissions and fuel consumption reductions, making them relatively effective
technologies.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-100 Effectiveness (Percent Reduction in CO2 Emissions and Fuel Consumption) of Technologies for
the Box Van Subcategories
AERODYNAMICS
DELTA CDA (M2)
DRY VAN
REFRIGERATED VAN
Long
Short
Long
Short
Bin I
0.0
0%
0%
0%
0%
Bin II
0.1
1%
1%
1%
1%
Bin III
0.4
3%
3%
3%
3%
Bin IV
0.7
5%
5%
5%
5%
Bin V
1.0
7%
7%
7%
7%
Bin VI
1.4
9%
10%
9%
10%
Bin VII
1.8
12%
13%
12%
13%
Tire Rolling Resistance
CRR (kg/ton)
Dry Van
Refrigerated Van
Long
Short
Long
Short
Level 2 (Baseline)
6.0
0%
0%
0%
0%
Level 3
5.1
2%
1%
2%
1%
Level 4
4.7
3%
2%
3%
2%
Weight Reduction
Weight (lb)
Dry Van
Refrigerated Van
Long
Short
Long
Short
Baseline
0
0%
0%
0%
0%
Option 1
100
0%
0%
0%
0%
Option 2
500
1%
1%
1%
1%
Option 3
1000
1%
2%
1%
2%
Option 4
2000
2%
4%
2%
4%
2.10.3 Defining the Baseline Trailers
2.10.3.1 No-Control Default Tractor-Trailer Vehicles within GEM
The regulatory purpose of EPA's heavy-duty vehicle compliance tool, GEM, is to
combine the effects of trailer technologies through simulation so that they can be expressed as
kg/ton-mile and gal/100 ton-mile and thus avoid the need for direct testing of each trailer model
being certified. The trailer program has separate standards for each trailer subcategory, and a
unique tractor-trailer vehicle was chosen to represent each subcategory for compliance. In the
Phase 2 update to GEM, each trailer subcategory is modeled as a particular trailer being pulled
by a standard tractor depending on the physical characteristics and use pattern of the trailer.
Table 2-101 highlights the relevant vehicle characteristics for the no-control default tractor-
trailer of each subcategory. Level 1 trailer tires are used, and the drag area, which is a function
of the aerodynamic characteristics of both the tractor and trailer, is set to the Bin I values shown
previously in Table 2-96. Weight reduction and tire pressure systems are not applied in these
baselines. In general, long box vans are pulled by sleeper cab tractors, and short box vans are
pulled by 4x2 day cabs.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-101 Characteristics of the No-Control Default Tractor-Trailer Vehicles in GEM

DRY VAN
REFRIGERATED VAN
Trailer Length
Long
Short
Long
Short
Standard Tractor




Class
Class 8
Class 7
Class 8
Class 7
Cab Type
Sleeper
Day
Sleeper
Day
Roof Height
High
High
High
High
Axle Configuration
6x4
4x2
6x4
4x2
Engine
2018 MY
2018 MY
2018 MY
2018 MY

15L, 455 HP
11L,350 HP
15L, 455 HP
11L, 350 HP
Steer Tire RR (kg/ton)
6.54
6.54
6.54
6.54
Drive Tire RR (kg/ton)
6.92
6.92
6.92
6.92
Drag Area, C,iA (m2)
6.0
5.6
6.0
5.6
Number of Trailer Axles
2
1
2
1
Trailer Tire RR (kg/ton)
6.00
6.00
6.00
6.00
Total Weight (kg)
31978
18306
33778
20106
Payload (tons)
19
10
19
10
Tire Pressure System Use
0
0
0
0
Weight Reduction (lb)
0
0
0
0
Drive Cycle Weightings




65-MPH Cruise
86%
64%
86%
64%
55-MPH Cruise
9%
17%
9%
17%
Transient Driving
5%
19%
5%
19%
2.10.3.2 Baseline Tractor-Trailer Vehicles to Evaluate Benefits and Costs
In order to evaluate the benefits and costs of the standards, it is necessary to establish a
reference point for comparison. The trailer technologies described in this section exist in the
market today, and their adoption is driven by available fuel savings as well as by the voluntary
SmartWay Partnership and California's Heavy Duty Greenhouse Gas Emission Reduction
Measure tractor-trailer requirements. To estimate the costs and benefits for these rules, the
agencies identified baseline tractor-trailers for each trailer subcategory based on the technology
adoption rates we project would exist if this trailer program was not implemented.
The agencies received comments suggesting our baseline adoption rates were too low for
several technologies and we made changes to our baseline trailers that in most cases should
address the comments. First, we created separate baselines for box vans that qualify as full-aero,
partial-aero and non-aero. We believe market forces will not significantly drive adoption of
CO2- and fuel-consumption reducing technologies for trailers with work performing equipment
(e.g., lift gates) and we are accordingly projecting zero adoption of the technologies in the
baselines for partial-and non-aero box vans. Similarly, we project zero adoption of these
technologies for the non-box trailers. We updated the baseline tire rolling resistance level for
non-box trailers to reflect the lower 6.5 kg/ton value in response to RMA's comment that these
trailers have different operational characteristics and should not have the same baseline tires as
box vans.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
An informal survey of TTMA members in 2014 indicated that 35 percent of long vans
and less than 2 percent of vans under 53-foot in length include aerodynamic devices, yet over 80
percent have adopted lower rolling resistance tires. The agencies believe the trailers for which
manufacturers have adopted these technologies are likely to be trailers that would qualify as
"full-aero" vans, and we created separate baselines to reflect these values. We project that
aerodynamics will increase to 40 percent adoption for full-aero long vans (dry and refrigerated)
and 5 percent for full-aero short vans by 2018 without this rulemaking. We project adoption of
lower rolling resistance tires (Level 3) to 90 percent and ATIS to 45 percent. We held these
adoption rates constant throughout the timeframe of the rules. Table 2-102 summarizes the
updated baseline trailers for each trailer subcategory.
Table 2-102 Adoption Rates and Average Performance Parameters for the Flat Baseline Trailers
TECHNOLOGY
LONG
SHORT
ALL PARTIAL-AERO,
ALL NON-BOX

VANS
VANS
NON-AERO VANS
TRAILERS
Aerodynamics
Bin I
55%
95%
100%
100%
Bin II

5%


Bin III
40%



Bin IV
5%



Bin V




Bin VI




Bin VII




Average Delta CdA (m2) a
0.2
0.0
0.0
0.0
Tire Rolling Resistance
Level 1



100%
Level 2
10%
10%
100%

Level 3
90%
90%


Level 4




Average Crr (kg/ton) a
5.2
5.2
6.0
6.5
Tire Pressure Systems
ATIS
45%
30%


TPMS




Average % Reduction a
0.5%
0.3%
0.0%
0.0%
Weight Reduction
Weight (lb) h
Notes:
a Combines adoption rates with performance levels shown in Table 2-99
b Weight reduction was not projected for the baseline trailers
Also shown in Table 2-102 are average aerodynamic performance (delta CdA), average
tire rolling resistance (CRR), and average reductions due to use of tire pressure and weight
reduction for each stage of the program. These values indicate the performance of theoretical
average tractor-trailers that the agencies project would be in use if no federal regulations were in
place for trailer CO2 and fuel consumption. These average tractor-trailer vehicles serve as
baselines for each trailer subcategory.
Because the agencies cannot be certain about future trends, we also considered a second
baseline. This dynamic baseline reflects the possibility that absent a Phase 2 regulation, there
will be continuing adoption of aerodynamic technologies in the long box trailer market after
2018 that reduce fuel consumption and CO2 emissions. This case assumes the research funded

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
and conducted by the federal government, industry, academia and other organizations will, after
2018, result in the adoption of additional aerodynamic technologies beyond the levels required to
comply with existing regulatory and voluntary programs. One example of such research is the
Department of Energy Super Truck program which had a goal of demonstrating cost-effective
measures to improve the efficiency of Class 8 long-haul freight trucks by 50 percent by 2015.ฐ
This baseline assumes that by 2040, 75 percent of new full-aero long vans will be equipped with
SmartWay-verified aerodynamic devices. The agencies project that the lower rolling resistance
tires and ATIS adoption will remain constant. Table 2-103 shows the agencies' projected
adoption rates of technologies in the dynamic baseline.
Table 2-103 Projected Adoption Rates and Average Performance Parameters for the Dynamic Baseline for
Long Dry and Refrigerated Vans (all other trailers are the same as Table 2-102)
TECHNOLOGY
LONG DRY AND REFRIGERATED
Model Year
2018
2021
2024
2027
2040
Aerodynamics





Bin I
55%
50%
45%
40%
20%
Bin II





Bin III
40%
45%
50%
55%
75%
Bin IV
5%
5%
5%
5%
5%
Bin V





Bin VI





Bin VII





Average Delta CdA (m2) a
0.2
0.3
0.3
0.3
0.4
Tire Rolling Resistance





Level 1





Level 2
10%
10%
10%
10%
10%
Level 3
90%
90%
90%
90%
90%
Level 4





Average Crr (kg/ton) a
5.2
5.2
5.2
5.2
5.2
Tire Inflation





ATIS
45%
45%
45%
45%
45%
TPMS





Average % Reduction a
0.5%
0.5%
0.5%
0.5%
0.5%
Weight Reduction (lbs)





Weighth





Notes:
A blank cell indicates a zero value
a Combines adoption rates with performance levels shown in Table 2-99
b Weight reduction was not projected for the baseline trailers
The agencies applied the vehicle attributes from Table 2-101 and the average
performance values from Table 2-102 in the Phase 2 GEM vehicle simulation to calculate the
CO2 emissions and fuel consumption performance of the reference tractor-trailers. The results of
these simulations are shown in Table 2-104. We used these CO2 and fuel consumption values to
calculate the relative benefits of the standards. Note that the large difference between the per
0 Daimler Truck North America. SuperTruck Program Vehicle Project Review. June 19, 2014. Docket EPA-HQ-
OAR-2014-0827.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
ton-mile values for long and short trailers is due primarily to the large difference in assumed
payload (19 tons compared to 10 tons) and the differing drive cycles as seen in Table 2-101. The
small difference between the dry and refrigerated vans of the same length is due to the weight
difference between the subcategories. Refrigerated vans have an additional 1800 pounds added
to account for the TRU. The alternative baseline in Table 2-103 impacts the long-term
projections of benefits beyond 2027, which are analyzed in Chapters 5 through 7 of this RIA.
The non-box trailers and non-aero box vans are not included in this baseline analysis, because we
are adopting design standards for these trailers. As such, these trailers would not have standards
to meet. Instead, they would have minimum tire technology requirements.
Table 2-104 CO2 Emissions and Fuel Consumption Results for the Baseline Tractor-Trailers

FULL-AERO
DRY VAN
FULL-AERO
REFRIGERATED
VAN
PARTIAL-AERO
DRY VAN
PARTIAL-AERO
REFRIGERATED VAN
Length
Long
Short
Long
Short
Long
Short
Long
Short
CO2 Emissions
(g/ton-mile)
83.2
126.5
84.9
130.3
86.1
128.5
87.9
132.4
Fuel
Consumption
(gal/1000 ton-
miles)
8.17289
12.42633
8.33988
12.79961
8.45776
12.62279
8.63458
13.00589
2.10.4 Effectiveness and Costs of the Standards
The agencies evaluated several alternatives for the trailer program. The analysis below is
for the alternative we believe reflects the agencies' statutory authorities. This alternative is fully
implemented in model year (MY) 2027.
2.10.4.1 Projected Technology Adoption Rates for the Final Standards
The agencies designed the trailer program to have no averaging in MY 2018 through MY
2026. In those years, all box vans sold must meet the standards using any combination of
available technologies. In MY 2027, when the trailer manufacturers are more comfortable with
compliance and the industry is more familiar with the technologies, the agencies are adopting
averaging provisions to allow additional flexibility for the full-aero box van subcategories that
have the most stringent standards. See Section IV.F(5)(a) of the Preamble to this rulemaking for
additional information about averaging. Table 2-105 through Table 2-107 present sets of
assumed adoption rates for aerodynamic, tire, and tire pressure technologies that a manufacturer
could apply to meet the box van standards. Since the agencies are not adopting averaging for
MY 2018-MY 2026, the adoption rates consist of the combination of a single aerodynamic bin,
tire rolling resistance level, and tire pressure system. As mentioned previously, manufacturers
can choose other combinations to meet the standards.
The adoption rates in Table 2-98 begins with all long box trailers achieving current
SmartWay-level aerodynamics (Bin III) in MY 2018 with a stepwise progression to achieving
Bin V in 2024. The adoption rates for short box trailers assume no adoption of aerodynamic

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
devices in MY 2018, adoption of single aero devices in MY 2021, and combinations of devices
by MY 2024. The shorter lengths of these trailers can restrict the design of aerodynamic
technologies that fully match the SmartWay-like performance levels of long boxes and we don't
assume adoption at the same Bin-levels. We nevertheless expect that trailer and device
manufacturers will continue to innovate skirt, under-body, rear, and gap-reducing devices and
combinations to achieve improved aerodynamic performance on these shorter trailers.
The MY 2027 standards for the full-aero box vans are based on an averaging program.
The gradual increase in assumed adoption of aerodynamic technologies throughout the phase-in
to the MY 2027 standards recognizes that even though many of the technologies are available
today and technologically feasible throughout the phase-period, their adoption on the scale of the
program will likely take time. EPA's aerodynamic testing does not show technologies capable
of achieving Bin VI for long vans or Bin IV for short vans. As a result, we did not assume a
similar step-wise progression to 100 percent adoption of those bins. We do believe that the
interim standards provide an incentive to drive innovation over the 10 years leading up to MY
2027 and that aerodynamic improvements at these highest performance levels will be possible
when the program is fully implemented.
We are aware that there is already a high adoption of SmartWay-verified tires (Level 3)
and we expect most manufacturers will install these tires to meet the standards in MY 2018, and
will adopt even lower rolling resistance tires as they become available. By MY 2021, we project
that adoption of Level 4 tires will be used to meet the standards. The agencies are also assuming
that all box vans will adopt ATIS throughout the program, though manufacturers do have the
option to install TPMS if they would prefer to make up the difference using other technologies.
As mentioned previously, the agencies did not include weight reduction in their technology
adoption projections, but certain types of weight reduction could be used as a compliance
pathway.
The agencies proposed that the partial-aero box vans would track with the full-aero van
standards until MY 2024. Wabash commented that these trailers would not be able to meet
standards after MY 2021. The agencies reconsidered the partial-aero standards and recognize
that it would be difficult to meet the proposed MY 2024 standards without the use of multiple
devices and that partial-aero trailers, by definition, are restricted from using multiple devices.
For these reasons, the agencies redesigned the partial-aero standards, such that trailers with
qualifying work-performing equipment can meet standards that would be achievable with the use
of a single aerodynamic device throughout the program. The partial-aero standards do, however,
increase in stringency slightly in MY 2021 to reflect the use of improved lower rolling resistance
tires.
Similar to our analyses of the baseline cases, the agencies derived a single set of
performance parameters for each subcategory by weighting the performance levels included in
Table 2-99 by the corresponding adoption rates. These performance parameters represent a
compliant vehicle for each trailer subcategory and we present these values in the tables.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-105 Projected Adoption Rates and Average Performance Parameters for Long Box Vans
TECHNOLOGY
LONG BOX
DRY & REFRIGERATED VANS
Model Year
2018
2021
2024
2027
Aerodynamic Technologies
Bin I




Bin II




Bin III
100%



Bin IV

100%


Bin V


100%
30%
Bin VI



70%
Bin VII




Average Delta CdA (m2) a
0.4
0.7
1.0
1.3
Trailer Tire Rolling Resistance
Level 1




Level 2



5%
Level 3
100%



Level 4

100%
100%
95%
Average Crr (kg/ton) "
5.1
4.7
4.7
4.8
Tire Pressure Systems
ATIS
100%
100%
100%
100%
TPMS




Average Reduction (%>) a
1.2%
1.2%
1.2%
1.2%
Weight Reduction
Weight (lb) h
Notes:
A blank cell indicates a zero value
a Combines projected adoption rates with performance levels shown in Table 2-99
b This set of adoption rates did not apply any assumed weight reduction to meet these standards for these trailers

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-106 Projected Adoption Rates and Average Performance Parameters for Short Box Vans
TECHNOLOGY

SHORT BOX


DRY & REFRIGERATED VANS
Model Year
2018
2021
2024
2027
Aerodynamic Technologies
Bin I




Bin II

100%


Bin III


100%
40%
Bin IV



60%
Bin V




Bin VI




Bin VII




Average Delta CdA (m2) h
0.0
0.1
0.4
0.6
Trailer Tire Rolling Resistance
Level 1




Level 2



5%
Level 3
100%



Level 4

100%
100%
95%
Average Crr (kg/ton) b
5.1
4.7
4.7
4.8
Tire Pressure Systems
ATIS
100%
100%
100%
100%
TPMS




Average Reduction (%)c
1.2%
1.2%
1.2%
1.2%
Weight Reduction
Weight (lb) h
Notes:
A blank cell indicates a zero value
a The majority of short box trailers are 28 feet in length. We recognize that they are often operated in tandem, which limits the
technologies that can be applied (for example, boat tails).
b Combines projected adoption rates with performance levels shown in Table 2-99
c This set of adoption rates did not apply any assumed weight reduction to meet these standards for these trailers

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-107 Projected Adoption Rates and Average Performance Parameters for Partial-Aero Box Vans
TECHNOLOGY
PARTIAL-AERO
PARTIAL-AERO

LONG BOX VANS
SHORT BOX VANS
Model Year
2018
2021+
2018
2021+
Aerodynamic Technologies
Bin I




Bin II



100%
Bin III
100%
100%


Bin IV




Bin V




Bin VI




Bin VII




Bin VIII




Average Delta CjA (m2) h
0.4
0.4
0.0
0.1
Trailer Tire Rolling Resistance
Level 1




Level 2




Level 3
100%

100%

Level 4

100%

100%
Average Crr (kg/ton) b
5.1
4.7
5.1
4.7
Tire Pressure Systems
ATIS
100%
100%
100%
100%
TPMS




Average Reduction (%) c
1.2%
1.2%
1.2%
1.2%
Weight Reduction
Weight (lb) h
Notes:
A blank cell indicates a zero value
a Combines projected adoption rates with performance levels shown in Table 2-99
b This set of adoption rates did not apply weight reduction to meet these standards for these trailers
The adoption rates shown in these tables are one set of many possible combinations that
box trailer manufacturers could apply to achieve the same average stringency. If a manufacturer
chose these adoption rates, a variety of technology options exist within the aerodynamic bins,
and several models of LRR tires exist for the levels shown. Alternatively, technologies from
other aero bins and tire levels could be used to comply. It should be noted that van
manufacturers are not limited to specific aerodynamic and tire technologies, since these are
performance-based standards, and manufacturers will not be constrained to adopt any particular
way to demonstrate compliance. Certain types of weight reduction, for example, may be used as
a compliance pathway.
Non-aero box vans with two or more work-related special components, and non-box
trailers (tankers, flatbeds, and container chassis) are not shown in the tables above, because they
have design-based tire standards. These trailers will install tires that meet a specified rolling
resistance and tire pressure systems. A tire-based program significantly reduces the compliance
burden for these manufacturers by reducing the amount of tracking and eliminating the need to
run GEM (or utilize the equation derived from GEM). The agencies are adopting these tire-only
requirements in two stages. In MY 2018, manufacturers would be required to use tires meeting a
rolling resistance of Level 3 or better and install tire pressure systems on all non-aero box vans.
Non-box trailers would also need tire pressure systems, but their tire rolling resistance threshold

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
is Level 2. In model years 2021 and later, these trailers would continue to install tire pressure
systems, but an additional level of rolling resistance is required. At minimum, manufacturers of
non-aero box vans and non-box trailers must install TPMS to comply with the standard;
however, they have the option to install ATIS though they will not receive any additional credit
for doing so. The agencies are assuming, as shown in Table 2-108, that manufacturers of these
trailers would adopt TPMS at all stages of the program.
Table 2-108 Design Standard Tire Technology Requirements for the Non-Aero Box Van and Non-Box
Trailers
TECHNOLOGY
NON-AERO BOX VANS
NON-BOX TRAILERS
Model Year
2018
2021+
2018
2021+
Minimum CRR (kg/ton)
5.1
4.7
6.0
5.1
Tire Pressure System
TPMS or ATIS
TPMS or ATIS
TPMS or ATIS
TPMS or ATIS
2.10.4.2 Derivation of the Standards
The average performance parameters from the previous tables were applied as input
values to the GEM vehicle simulation to derive the HD Phase 2 fuel consumption and CO2
emissions standards for each subcategory of box trailers.
The standards are shown in Table 2-109 and Table 2-110. Over the four stages of the
trailer program, the full-aero box vans longer than 50 feet will reduce their CO2 emissions and
fuel consumption by two percent, five percent, seven percent and nine percent compared to their
flat baselines for each year in Table 2-104. Full-aero box vans 50-feet and shorter will achieve
reductions of one percent, two percent, four percent and six percent compared to their flat
baseline cases. The partial-aero long and short box van standards will reduce CO2 and fuel
consumption by six percent and four percent, respectively, by MY 2021. The design-based tires
standards for non-box trailers and non-aero box vans would provide reductions of two percent in
MY 2018 and three percent in MY 2021 and later.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-109 Standards for Full-Aero Box Vans
MODEL
YEAR
SUBCATEGORY
DRY VAN
REFRIGERATED VAN
Length
Long
Short
Long
Short
2018 -
2020
EPA Standard
(CO 2 Grams per Ton-Mile)
81.3
125.4
83.0
129.1
Voluntary NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.98625
12.31827
8.15324
12.68173
2021 -
2023
EPA Standard
(CO 2 Grams per Ton-Mile)
78.9
123.7
80.6
127.5
NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.75049
12.15128
7.91749
12.52456
2024 -
2026
EPA Standard
(CO 2 Grams per Ton-Mile)
77.2
120.9
78.9
124.7
NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.58350
11.87623
7.75049
12.24951
2027 +
EPA Standard
(CO 2 Grams per Ton-Mile)
75.7
119.4
77.4
123.2
NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.43615
11.72888
7.60314
12.10216
Table 2-110 Standards for Partial-Aero Box Vans
MODEL
YEAR
SUBCATEGORY
DRY VAN
REFRIGERATED VAN
LENGTH
LONG
SHORT
LONG
SHORT
2018 -2020
EPA Standard
(CO2 Grams per Ton-Mile)
81.3
125.4
83.0
129.1
Voluntary NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.98625
12.31827
8.15324
12.68173
2021 +
EPA Standard
(CO2 Grams per Ton-Mile)
80.6
123.7
82.3
127.5
NHTSA Standard
(Gallons per 1,000 Ton-Mile)
7.91749
12.15128
8.08448
12.52456
2.10.4.3 Projected Cost of Trailer Standards
The agencies evaluated technology costs for 53-foot dry and refrigerated vans and 28-
foot dry vans, which we believe are representative of the majority of trailers in the long and short
box trailer categories, respectively. Similar tire technology costs were assumed for the non-box
trailer subcategory. We identified costs for each technology package evaluated and projected out
the costs for each year of the program. A summary of the technology costs is included in Table
2-111 through Table 2-114 for the four phases of the trailer program, with additional details
available in RIA Chapter 2.12. Costs shown in the following tables are for the specific model
year indicated and are incremental to the average baseline costs, which includes some level of
adoption of these technologies as shown in Table 2-102. For example, the tire costs for the full-
aero subcategories are $l-$2, because there is already a very high adoption of LRR tires in the
baseline. Therefore, the technology costs in the following tables reflect the average cost
expected for each of the indicated trailer subcategories. Throughout the trailer program
discussion, the non-aero box van subcategory is treated as a single category, because all lengths
of these trailers have identical design standards. However, two costs for this subcategory are

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
shown to reflect the difference in the number of tires expected on the different length trailers
(i.e., long vans are assumed to have two axles and eight tires, while short vans have a single axle
and four tires).
Note that these costs do not represent actual costs for the individual components, because
some fraction of the component costs has been subtracted to reflect some use of these
components in the baseline. These costs include indirect costs via markups along with learning
impacts and also reflect estimated costs of the compliance process. For more on the estimated
technology costs exclusive of adoption rates, refer to Chapter 2.12.
Table 2-111 Trailer Technology Incremental Costs in the 2018 Model Year
(2013$)

LONG
VANS,
FULL
AERO
LONG
VANS,
PARTIAL
AERO
SHORT
VANS,
FULL
AERO
SHORT
VANS,
PARTIAL
AERO
LONG
VANS,
NO
AERO
SHORT
VANS,
NO
AERO
NON-
BOX
Aerodynamics
$367
$742
$0
$0
$0
$0
$0
Tires
$2
$40
$1
$20
$40
$20
$28
Tire inflation
system
$347
$659
$338
$494
$421
$210
$421
Total
$716
$1,441
$339
$514
$461
$231
$448
Table 2-112 Trailer Technology Incremental Costs in the 2021 Model Year
(2013$)

LONG
VANS,
FULL
AERO
LONG
VANS,
PARTIAL
AERO
SHORT
VANS,
FULL
AERO
SHORT
VANS,
PARTIAL
AERO
LONG
VANS,
NO
AERO
SHORT
VANS,
NO
AERO
NON-
BOX
Aerodynamics
$743
$679
$450
$475
$0
$0
$0
Tires
$17
$49
$9
$25
$49
$25
$23
Tire inflation
system
$321
$609
$313
$457
$389
$195
$389
Total
$1,081
$1,337
$772
$957
$438
$219
$412

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-113 Trailer Technology Incremental Costs in the 2024 Model Year
	(2013$)	

LONG
LONG
SHORT
SHORT
LONG
SHORT
NON-

VANS,
VANS,
VANS,
VANS,
VANS,
VANS,
BOX

FULL
PARTIAL
FULL
PARTIAL
NO
NO


AERO
AERO
AERO
AERO
AERO
AERO

Aerodynamics
$899
$645
$879
$451
$0
$0
$0
Tires
$11
$48
$6
$24
$48
$24
$27
Tire inflation







system
$294
$558
$286
$418
$357
$178
$357
Total
$1,204
$1,251
$1,171
$894
$405
$202
$383
Table 2-114 Trailer Technology Incremental Costs in the 2027 Model Year
	(2013$)	

LONG
VANS,
FULL
AERO
LONG
VANS,
PARTIAL
AERO
SHORT
VANS,
FULL
AERO
SHORT
VANS,
PARTIAL
AERO
LONG
VANS,
NO
AERO
SHORT
VANS,
NO
AERO
NON-
BOX
Aerodynamics
$1,069
$623
$921
$436
$0
$0
$0
Tires
$22
$44
$11
$22
$44
$22
$16
Tire inflation
system
$279
$529
$272
$397
$338
$169
$338
Total
$1,370
$1,196
$1,204
$855
$382
$191
$354
2.10.5 Evaluation of Compliance Option using GEM-Based Equation
EPA created the Greenhouse gas Emissions Model (GEM) as a compliance tool for
heavy-duty vehicles. Users provide specific performance parameters to the model and GEM
calculates CO2 emissions and fuel consumption results. As described previously, the Phase 2
GEM is designed to accept four performance variables as trailer inputs: change in drag area
(delta CdA), tire rolling resistance level (TRRL), tire pressure systems, and weight reduction
(WR). The reduction applied when using a tire pressure system is accounted for after the vehicle
simulation is complete. The other performance parameters directly impact the results of the
vehicle simulation, by changing the drag, rolling resistance and weight of the simulated vehicle.
We performed a sensitivity analysis for delta CdA, TRRL and WR to evaluate their effect
on the model's results. In the analysis to follow, all of the calculations are shown in terms of
CO2 emissions; use a conversion of 10,180 grams CO2 per gallon of diesel fuel to calculate the
corresponding fuel consumption values. Figure 2-74 through Figure 2-77 show GEM's CO2
results from the proposal for a parameter sweep of a simulated Class 8 tractor pulling each of the
four box van trailers. It can be seen that each of the three parameters has a linear impact on CO2
emissions. A curve fit was applied to each data set and the equation is displayed on each plot.
The intercept in each parameter sweep data set is the baseline CO2 result considering a no-
control trailer, and this value is consistent for all parameters for a given trailer. The coefficients
indicate the relationship between the assessed parameter and the model's CO2 result. A similar
analysis was repeated with the GEM version that was updated since the NPRM. The coefficients
of the regression curves differ, but the trends remain the same.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Impact of AC DA Parameter
Long Dry Van, TRRL = 6.0 kg/ton, WR = 0 lb
90
ฆ| 85
ฆ
c
o
2 80
o
ฐ 75
70
ฆ	



	
••	
	-



		
"	_
y = -5.8216X
+ 86.066

'ฆ
0.0
0.5
1.0
Delta CDA (m2)
1.5
2.0
(a)
Impact of ATRRL Parameter
Long Dry Van, ACdA = 0 m2, WR = 0 lb
90
I 85
i
C
o
% 80
U)
oj
8 75
70
ฆ	















y = -1.667x + 86.072



-1.0 -0.5 0.0 0.5 1.0
Delta TRRL (kg/ton)
1.5
2.0
(b)
Impact ofWR Parameter
Long Dry Van, ACdA = 0 m2, TRRL = 6.0 kg/ton
90
f 85
l
c
o
2 80

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Impact of ACdA Parameter
Long Reefer, TRRL = 6.0 kg/ton, WR = 0 lb
90
ฆ| 85
ฆ
c
o
3 80
CM
O
ฐ 75
y = -5.7834X +87.915
70
0.0	0.5	1.0	1.5	2.0
Delta CDA (m2)
(a)
Impact of ATRRL Parameter
Long Reefer, ACDA = 0 m2, WR = 0 lb
90
f 85
C
0
1	80
CM
o
o 75










y = -1.7506x +87.919



70
-1.0 -0.5 0.0 0.5 1.0 1.5 2.0
Delta TRRL (kg/ton)
(b)
Impact of WR Parameter
Long Reefer, ACDA = 0 m2, TRRL = 6.0 kg/ton
90
ฃ 85
C
o
3 80
CM
O
ฐ 75
70
y = -0.001X + 87.896
0	1000 2000 3000 4000 5000
Weight Reduction (lb)
(c)
Figure 2-75 Impact of (a) Delta CdA, (b) Delta Crr, and (c) Weight Reduction on CO2 Results of a GEM-
Simulated Long Refrigerated Van

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Impact of ACdA Parameter
Short Dry Van, TRRL = 6.0 kg/ton, WR = 0 lb
140
- 130
E
I 120
3
n 110
o
o
100
y = -9.4835X + 130.18
90
0.0	0.5	1.0	1.5	2.0
Delta CDA (m2)
(a)
Impact of ATRRL Parameter
Short Dry Van, ACDA = 0 m2, WR = 0 lb
140
_ 130
I
| 120
D)
-110
o
ฐ 100
B	





















y = -1.7801x + 128.43



90
-1.0 -0.5 0.0 0.5 1.0 1.5 2.0
Delta TRRL (kg/ton)
(b)
Impact of WR Parameter
Short Dry Van, ACDA = 0 m2, TRRL = 6.0 kg/ton
140
=r130
ฃ
i
o 120
O 110
o
100
90
y = -0.0026X + 128.33
0	1000 2000 3000 4000 5000
Weight Reduction (lb)
(c)
Figure 2-76 Impact of (a) Delta CdA, (b) Delta Crr, and (c) Weight Reduction on CO2 Results of a GEM-
Simulated Short Dry Van

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Impact of ACdA Parameter
Short Reefer, TRRL = 6.0 kg/ton, WR = 0 lb

140

130
1

c
0
120
3

CM
110
O

O


100

90
y = -9.3557x + 134.25
0.0	0.5	1.0	1.5	2.0
Delta CDA (m2)
(a)
Impact of ATRRL Parameter
Short Reefer, ACDA = 0 m2, WR = 0 lb
140
130
ง 120
1	






















y = -1.8839x+132.37



110
100
90
-1.0 -0.5 0.0 0.5 1.0 1.5 2.0
Delta TRRL (kg/ton)
(b)
Impact of WR Parameter
Short Reefer, ACDA = 0 m2, TRRL = 6.0 kg/ton
140
^130
E
I 120
g 110
o
100
90
y = -0.0026x + 132.3
0	1000 2000 3000 4000 5000
Weight Reduction (lb)
(c)
Figure 2-77 Impact of (a) Delta CdA, (b) Delta Crr, and (c) Weight Reduction on CO2 Results of a GEM-
Simulated Short Refrigerated Van
Additional GEM simulations were performed for each of the four box trailer
subcategories to assess the combined effect of these parameters. As seen in Figure 2-78 and
Figure 2-79 for the long dry van simulation, the coefficients of the curve fit equations were not

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
significantly changed, indicating that the combined impacts of these parameters on GEM's CO2
results were additive. Similar trends were seen with the simulations for the other trailer
subcategories, though the results are not shown here.
90
— 85

c
o
80
O)
Combined Impact of ACdA and TRRL
(WR = 0 lb)
ฆTRRL=7.0, WR=0 OTRRL=6.0, WR=0 ATRRL=4, WR=0
o
A
o
o
75
70
y = -5.8x +87.7
y = -5.8x + 86.1
y = -5.8x + 82.7
0.0
0.5
o
A
1.0
Delta CdA (m2)
o
A
1.5
o
A
2.0
Figure 2-78 Combined Impact of Drag Area and Tire Rolling Resistance Level on CO2 Results of a GEM-
Simulated Long Dry Van with No Weight Reduction
Combined Impact of ACdA and WR
(TRRL = 6.0 kg/ton)
90
C
O
^80
O)
O
0 75
70
ฆTRRL=6.0, WR=0 OTRRL=
J*	
6.0, WR=1000 ATRRL=6, WR=2000

1.

y = -5.8x +86.1

	 .
y = -5.8x +85.0
y = -5.7x + 84.0

-	
0.0
0.5
1.0
Delta CdA (m2)
1.5
2.0
Figure 2-79 Combined Impact of Drag Area and Weight Reduction on CO2 Results of a GEM-Simulated
Long Dry Van at a Tire Rolling Resistance Level of 5.1 kg/ton
The results presented Figure 2-78 and Figure 2-79 suggest that these parameters could be
combined into a single equation to calculate CO2 emissions. Equation 2-3 is the result of
combining the updated curve fit equations for long box dry vans.
Equation 2-3 Combination of Curve Fit Equations for Long Dry Van GEM Input Parameters
y = 86.1-1. 7(ATRRL) - 5.8(ACDA) - 0. 0010(Wi?)

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Our regulations specify that TRRL be an absolute measure of a tire's coefficient of
rolling resistance (not a change in rolling resistance). As a result, Equation 2-3 was modified
such that the variables of the equation matched the trailer inputs required by GEM. Equation 2-4
is the resulting equation.
Equation 2-4 Modified Equation for Long Dry Vans to Account for TRRL Input Parameter
y = 16.1 + 1. 7(TRRL) - 5.8(ACDA) - 0. 0010(Wi?)
Each of the trailer subcategories follows the same general format and a generic equation
is shown in Equation 2-5. Table 2-115 summarizes the corresponding constants for each of the
trailer subcategories.
Equation 2-5 General GEM-Based CO2 Equation for Trailer Subcategories
eC02 = Ct + C2(TRRL) + C3(ACdA) + C4(WR)
Table 2-115 Constants for GEM-Based CO2 Equation for Trailer Subcategories (See Equation 2-5)
TRAILER SUBCATEGORY
Ci
c2
c3
c4
Long Dry Van
76.1
1.67
-5.82
-0.00103
Long Refrigerated Van
77.4
1.75
-5.78
-0.00103
Short Dry Van
117.8
1.78
-9.48
-0.00258
Short Refrigerated Van
121.1
1.88
-9.36
-0.00264
Over 100 GEM vehicle simulations were performed for a range of delta CdA, TRRL and
weight reduction values. The results of these simulations were compared to CO2 results
calculated using Equation 2-5 for each trailer subcategory. The following figures show the
equation and GEM have nearly identical CO2 results.

-------
*** E. O. 12866 Review — Revised - Do Not Cite, Quote, or Release During Review ***
Compare GEM and Calculated C02 Results
Long Dry Van
y = 1.02x-1.6274
Ra = 0.9995
ซ 80
a> 70
CO2 = 76.1 + 1.7 CRR - 5.8 ACdA - 0.0010 WR
o 65
GEM Simulation CQ2 Result (g/ton-mi)
Figure 2-80 Comparison of GEM and Calculated CO2 Results for a Long Dry Van
Compare GEM and Calculated CQ2 Results
Long Refrigeraged Van
y = 1.0198X-1.6407
R! = 0.9995
O 75
CO2 = 77.4 + 1.8 CRR - 5.8 ACdA - 0.0010 WR
iJ 65
95
GEM Simulation C02 Result (g/ton-mi)
Figure 2-81 Comparison of GEM and Calculated CO2 Results for a Long Refrigerated Van

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
Compare GEM arid Calculated C02 Results
_	Short Dry Van
| 135
O 130
3 125
3 120
w
ซ 115
(M 110
0	105
"g 100
1	95
o 90
o 90 95 100 105 110 115 120 125 130 135
GEM Simulation C02 Result (g/ton-mi)
Figure 2-82 Comparison of GEM and Calculated CO2 Results for a Short Dry Van
Compare GEM and Calculated C02 Results
_	Short Refrigerated Van
? 140
| 135
3 130
3 125
| 120
cm 115
o 110
~5 105
ซ 100
J 95
O 95 100 105 110 115 120 125 130 135 140
Calculated C02 Result (g/ton-mi)
Figure 2-83 Comparison of GEM and Calculated CO2 Results for a Short Refrigerated Van
The comparisons shown in Figure 2-80 through Figure 2-83 suggest that an equation may offer a simplified
approach for trailer manufacturers to calculate CO2 without the use of GEM. Equation 2-6 below is a slight
modification to Equation 2-5. As mentioned previously, the trailer program is also offering the use of tire
pressure systems as a means achieving the standards. This parameter is not considered in Equation 2-5.
Equation 2-6 includes a constant, Cs, to address the use of tire pressure systems. Constant Cs is equal to
unity (1.0) for trailers that do not have tire pressure systems installed, equal to 0.988 (accounting for the 1.2
percent reduction) for trailers that include ATIS, and equal to 0.990 for trailers that include TPMS. As
y = 1.0336X-3.9652
Rs = 0.9991
C02 = 118 + 1.8 CRR-9.5 ACdA - 0.0026 WR
y = 1.0327X -4.0149
R2 = 0.9992
CO2 = 121 + 1.9 CRR - 9.3 ACdA - 0.0027 WR

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
mentioned previously, one can use a conversion factor of 10,180 grams CO2 per gallon of diesel fuel to
calculate the corresponding fuel consumption values.
Table 2-116 summarizes the constants available to manufacturers when using Equation
2-6 for compliance.
Equation 2-6 GEM-Based Compliance Equation for Phase 2 Trailer Program
eC02 = [Ci + C2 ฆ (TRRL) + C3 ฆ (ACDA) + C4 ฆ (WR)] ฆ C5
Table 2-116 Constants for GEM-Based CO2 Equation for Trailer Subcategories (See Equation 2-6)
TRAILER
SUBCATEGORY
Ci
C2
C3
c4
C5
No Tire
Pressure
System
ATIS
Installed
TPMS
Installed
Long Dry Van
76.1
1.67
-5.82
-0.00103
1.000
0.988
0.990
Long Refrigerated Van
77.4
1.75
-5.78
-0.00103
Short Dry Van
117.8
1.78
-9.48
-0.00258
Short Refrigerated Van
121.1
1.88
-9.36
-0.00264
The updates to GEM that were made following the NPRM impacted the trailer model and
resulted in a change to the constants for the GEM-based compliance equation that will be used
by trailer manufacturers. We repeated the process of generating and validating the new
constants, and, similar to the proposal, these updated values accurately recreate the GEM
calculations for each trailer subcategory. Consequently, the agencies are adopting this equation-
based compliance approach with the new constants shown in Table 2-116 for the final Phase 2
trailer program.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11 Technology Costs
2.11.1 Overview of Technology Cost Methodology Learning Effects on
Technology Costs
Chapter 2.11.1.2 presents the methods used to address indirect costs in this analysis.
Chapter 2.11.1.3 presents the learning effects applied throughout this analysis. In Chapter 2.11.2
through 2.11.10 we present individual technology costs including: the direct manufacturing costs
(DMC), their indirect costs (IC) and their total costs (TC, TC=DMC+IC). Note that we also
present technology penetration rates for most technologies and the resultant total cost as applied
to a technology package (which we have denoted as TCp, where TCp=TC x Adoption Rate).
The tables presented show the adoption rate for, generally, alternatives la and 3 where la
represents the reference case (or the "no action" case) and 3 represents the preferred policy case
(i.e. the standards adopted in this final rule). Note also that some TCp values appear as negative
values in some tables (notably the lower rolling resistance (LRR) tire tables). This is because
certain LRR tires are expected in the reference case but are then expected to be removed in the
policy case and replaced by more aggressive LRR tires. In such cases, the reference case tires
show negative TCp costs since they are being removed and replaced.
2.11.1.1 Direct Manufacturing Costs
The direct manufacturing costs (DMCs) used throughout this analysis are derived from
several sources. Many of the tractor, vocational and trailer DMCs can be sourced to the Phase 1
rules which, in turn, were sourced largely from a contracted study by ICF International for
EPA.194 There was no serious disagreement regarding these estimated costs in the public
comments to the Phase 1 rules. We have updated those costs by converting them to 2012 dollars,
as described in Section IX.B.l.e of the Preamble, and by continuing the learning effects
described in the Phase 1 rules and in Section IX. B.l.c of the Preamble. The new tractor,
vocational and trailer costs can be sourced to a more recent study conducted by Southwest
Research Institute (SwRI) under contract to NHTS A.195 The cost methodology used by SwRI in
that study was to estimate retail costs then work backward from there to derive a DMC for each
technology. The agencies did not agree with the approach used by Tetra Tech to move from
retail cost to DMC as it disagreed with EPA's look at retail price equivalents in the HD engine
and truck industry on which EPA has based the indirect cost markup approach to estimate
indirect costs, as discussed more in Chapter 2.11.1.2. As such, the agencies have used an
approach consistent with past GHG/CAFE/fuel consumption rules by dividing estimated retail
prices by our estimated retail price equivalent markups to derive an appropriate DMC for each
technology. We describe our RPEs in Chapter 2.11.1.2.
For HD pickups and vans, we have relied primarily on the Phase 1 rules and the light-
duty 2017-2025 model year rule since most technologies expected on these vehicles are, in
effect, the same as those used on light-duty pickups. Many of those technology DMCs are based
on cost teardown studies which the agencies consider to be the most robust method of cost
estimation. However, many of the HD versions of those technologies would be expected to be
more costly than their light-duty counterparts because of the heavier HD vehicles and/or the
higher power and torque characteristics of their engines. Therefore, we have scaled upward

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
where appropriate many of the light-duty DMCs for this analysis. We have also used some costs
developed under contract to NHTSA by SwRI (the study mentioned above).196
Importantly, in our methodology, all technologies are treated as being sourced from a
supplier rather than being developed and produced in-house. As such, some portion of the total
indirect costs of making a technology or system—those costs incurred by the supplier for
research, development, transportation, marketing etc.—are contained in the sales price to the
engine and/or vehicle manufacturer (i.e., the original equipment manufacturer (OEM)). That sale
price paid by the OEM to the supplier is the DMC we estimate.
2.11.1.2 Indirect Costs
To produce a unit of output, engine and truck manufacturers incur direct and indirect
costs. Direct costs include cost of materials and labor costs. Indirect costs are all the costs
associated with producing the unit of output that are not direct costs - for example, they may be
related to production (such as research and development [R&D]), corporate operations (such as
salaries, pensions, and health care costs for corporate staff), or selling (such as transportation,
dealer support, and marketing). Indirect costs are generally recovered by allocating a share of
the costs to each unit of a good sold (e.g., an engine, a truck, etc.). Although it is possible to
account for direct costs allocated to each unit of good sold, it is more challenging to account for
indirect costs allocated to a unit of goods sold. To make a cost analysis process more feasible,
markup factors, which relate total indirect costs to total direct costs, have been developed. These
factors are often referred to as retail price equivalent (RPE) multipliers.
Cost analysts and regulatory agencies (including both EPA and NHTSA) have frequently
used these multipliers to predict the resultant impact on costs associated with manufacturers'
responses to regulatory requirements. The best approach, if it were possible, to determining the
impact of changes in direct manufacturing costs on a manufacturer's indirect costs would be to
actually estimate the cost impact on each indirect cost element. However, doing this within the
constraints of an agency's time or budget is not always feasible, or the technical, financial, and
accounting information to carry out such an analysis may simply be unavailable.
RPE multipliers provide, at an aggregate level, the relative shares of revenues (Revenue =
Direct Costs + Indirect Costs + Net Income) to direct manufacturing costs. Using RPE
multipliers implicitly assumes that incremental changes in direct manufacturing costs produce
common incremental changes in all indirect cost contributors as well as net income. However, a
concern in using the RPE multiplier in cost analysis for new technologies added in response to
regulatory requirements is that the indirect costs of vehicle modifications are not likely to be the
same for different technologies. For example, less complex technologies could require fewer
R&D efforts or less warranty coverage than more complex technologies. In addition, some
simple technological adjustments may, for example, have no effect on the number of corporate
personnel and the indirect costs attributable to those personnel. The use of RPEs, with their
assumption that all technologies have the same proportion of indirect costs, is likely to
overestimate the costs of less complex technologies and underestimate the costs of more
complex technologies. Table 2-117 shows the RPE factors used in developing indirect costs in
past, and this, agency analyses.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-117 Industry Retail Price Equivalent (RPE) Factors
INDUSTRY
RPE
Heavy engine manufacturers
1.28
Heavy truck manufacturers
1.36
Light-duty vehicle manufacturers
1.50
To address this concern, modified multipliers have been developed by EPA, working
with a contractor, for use in rulemakings. These multipliers are referred to as indirect cost
multipliers (or ICMs). In contrast to RPE multipliers, ICMs assign unique incremental changes
to each indirect cost contributor as well as net income.
ICM = (direct cost + adjusted indirect cost)/(direct cost)
Developing the ICMs from the RPE multipliers requires developing adjustment factors
based on the complexity of the technology and the time frame under consideration: the less
complex a technology, the lower its ICM, and the longer the time frame for applying the
technology, the lower the ICM. This methodology was used in the cost estimation for the recent
light-duty MYs 2012-2016 and MYs 2017-2025 rulemaking and for the heavy-duty MYs 2014-
2018 rulemaking. There was no serious disagreement with this approach in the public comments
to any of these rulemakings. The ICMs for the light-duty context were developed in a peer-
reviewed report from RTI International and were subsequently discussed in a peer-reviewed
journal article.197 Importantly, since publication of that peer-reviewed journal article, the
agencies have revised the methodology to include a return on capital (i.e., profits) based on the
assumption implicit in ICMs (and RPEs) that capital costs are proportional to direct costs, and
businesses need to be able to earn returns on their investments.
For the heavy-duty pickup truck and van cost projections in this rule, the agencies have
used ICM adjustment factors developed for light-duty vehicles, inclusive of a return on capital,
primarily because the manufacturers involved in this segment of the heavy-duty market are the
same manufacturers that build light-duty trucks.
For the combination tractors, vocational vehicles, and heavy-duty engine cost projections
in this rule, the agencies are again using the ICMs used in the HD Phase 1 rules. Those ICMs
were developed by RTI International under EPA contract to update EPA's methodology for
accounting for indirect costs associated with changes in direct manufacturing costs for heavy-
duty engine and truck manufacturers.198 In addition to the indirect cost contributors varying by
complexity and time frame, there is no reason to expect that the contributors would be the same
for engine manufacturers as for truck manufacturers. The resulting report from RTI provides a
description of the methodology, as well as calculations of the indirect cost multipliers that are
being used as the basis for the markups used in this rule. These indirect cost multipliers were
used, along with calculations of direct manufacturing costs, to provide estimates of the full
additional costs associated with new technologies.
As explained in the Phase 1 final rules, and entirely consistent with the analysis
supporting that program, the agencies have made some changes to both the ICM factors and to
the method of applying those factors relative to the factors developed by RTI and presented in

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
their reports. The first of these changes was done in response to continued thinking among the
agencies about how past ICMs have been developed and about which data sources are the most
appropriate on which to rely in determining the appropriate ICMs. The second change was done
in response to both staff concerns and public feedback suggesting that the agencies were
inappropriately applying learning effects to indirect costs via the multiplicative approach to
applying the ICMs.
Regarding the first change - to the ICM factors themselves - a little background must
first be provided. In the original work done under contract to EPA by RTI International,199 EPA
experts had undergone a consensus approach to determining the impact of specific technology
changes on the indirect costs of a company. Subsequently, EPA experts underwent a blind
survey to make this determination on a different set of technology changes. This subsequent
effort, referred to by EPA as a modified-Delphi approach, resulted in different ICM
determinations. This effort is detailed in a memorandum contained in the docket for this
rulemaking.200 Upon completing this effort, EPA determined that the original RTI values should
be averaged with the modified-Delphi values to arrive at the final ICMs for low and medium
complexity technologies and that the original RTI values would be used for high complexity
level 1 while the modified-Delphi values would be used for high complexity level 2. These final
ICMs were used in the 2012-2016 light-duty GHG/CAFE rulemaking. Subsequent to that, EPA
contracted with RTI to update their light-duty report with an eye to the heavy-duty industry. In
that effort, RTI determined the RPE of both the heavy-duty engine and heavy truck industries,
then applied the light-duty indirect cost factors—those resulting from the averaging of the values
from their original report with the modified-Delphi values—to the heavy-duty RPEs to arrive at
heavy-duty specific ICMs. That effort is described in their final heavy-duty ICM report
mentioned above.201
During development of the Phase 1 heavy-duty final rules, the agencies decided that the
original light-duty RTI values, given the technologies considered for low and medium
complexity, should no longer be used and that we should rely solely on the modified-Delphi
values for these complexity levels. The original light-duty RTI study used low rolling resistance
tires as a low complexity technology example and a dual clutch transmission as a medium
complexity technology. Upon further thought, the technologies considered for the modified
Delphi values (passive aerodynamic improvements for low complexity and turbocharging with
downsizing for medium complexity) were considered by the agencies to better represent the
example technologies. As a result, the modified-Delphi values were to become the working
ICMs for low and medium complexity rather than averaging those values with the original RTI
report values. The agencies have also re-examined the technology complexity categories that
were assigned to each light-duty technology and modified these assignments to better reflect the
technologies that are now used as proxies for each category. This decision impacted the low and
medium complexity heavy-duty ICMs too because the modified-Delphi values alone were to be
applied to the heavy-duty RPEs to arrive at heavy-duty ICMs rather than using the averaged
values developed for the light-duty 2012-2016 rulemaking.
A secondary-level change was also made as part of this ICM recalculation to the light-
duty ICMs and, therefore, to the ICMs used in the Phase 1 HD final rules and again in this
analysis for HD pickups and vans. That change was to revise upward the RPE level reported in
the original RTI report from an original value of 1.46 to 1.5 to reflect the long term average RPE.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The original RTI study was based on 2008 data. However, an analysis of historical RPE data
indicates that, although there is year to year variation, the average RPE has remained roughly
1.5. ICMs are applied to future year's data and therefore the agencies believed and continue to
believe that it is most appropriate to base ICMs on the historical average rather than a single
year's result. Therefore, ICMs were adjusted to reflect this average level. As a result, the High 1
and High 2 ICMs used for HD pickups and vans were changed for the Phase 1 final rules and we
continue to use those changed values here.
Table 2-118 shows the ICM values used in this rule. Near term values are used in early
years, depending on the technology, and account for differences in the levels of R&D, tooling,
and other indirect costs that would be incurred. Once the program has been fully implemented,
some of the indirect costs would no longer be attributable to the standards and, as such, a lower
ICM factor is applied to direct costs in later years.
Table 2-118 Indirect Cost Multipliers Used in this Analysis"
CLASS
COMPLEXITY
NEAR
TERM
LONG
TERM
HD Pickup Trucks and Vans
Low
1.24
1.19
Medium
1.39
1.29
Highl
1.56
1.35
High2
1.77
1.50
Loose diesel engines
Low
1.15
1.13
Medium
1.24
1.18
Highl
1.28
1.19
High2
1.44
1.29
Loose gasoline engines
Low
1.24
1.19
Medium
1.39
1.29
Highl
1.56
1.35
High2
1.77
1.50
Vocational Vehicles,
Combination Tractors and
Trailers
Low
1.18
1.14
Medium
1.30
1.23
Highl
1.43
1.27
High2
1.57
1.37
Note:
a Rogozhin, A., et. al., "Using indirect cost multipliers to estimate the total cost of adding
new technology in the automobile industry," International Journal of Production
Economics (2009); "Documentation of the Development of Indirect Cost Multipliers for
Three Automotive Technologies," Helfand, G., and Sherwood, T., Memorandum dated
August 2009; "Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers,"
Report prepared by RTI International and Transportation Research Institute, University of
Michigan, July 2010.
The second change made to the ICMs during development of the Phase 1 final rules had
to do with the way in which the ICMs were applied. Until that time, we had applied the ICMs,
as done in any analysis that relied on RPEs, as a pure multiplicative factor. This way, a direct
manufacturing cost of, say, $100 would have been multiplied by an ICM of 1.24 to arrive at a
marked up technology cost of $124. However, as learning effects (discussed below) are applied
to the direct manufacturing cost, the indirect costs are also reduced accordingly. Therefore, in
year 2 the $100 direct manufacturing cost might reduce to $97 and the marked up cost would

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
become $120 ($97 x 1.24). As a result, indirect costs have been reduced from $24 to $23. Given
that indirect costs cover many things such as facility-related costs, electricity, etc., it is perhaps
not appropriate to apply the ICM to the learned direct costs, at least not for those indirect cost
elements unlikely to change with learning. The agencies decided that it was more appropriate
only to allow warranty costs to decrease with learning since warranty costs are tied to direct
manufacturing costs (since warranty typically involves replacement of actual parts which should
be less costly with learning).p However, the remaining elements of the indirect costs should
remain constant year-over-year, at least until some of those indirect costs are no longer
attributable to the rulemaking effort that imposed them (such as R&D).
As a result, the ICM calculation became more complex with the analysis supporting the
Phase 1 final rules, and we continue to use that more complex calculation here. We first
establish the year in which the direct manufacturing costs are considered "valid." For example, a
cost estimate might be considered valid today, or perhaps not until high volume production is
reached in some future model year. That year is considered the base year for the estimated cost.
That cost is the cost used to determine the "non-warranty" portion of the indirect costs. For
example, the near term non-warranty portion of the loose diesel engine low complexity ICM is
0.149 (the warranty versus non-warranty portions of the ICMs are shown in Table 2-119). For
the improved water pump technology we have estimated a direct manufacturing cost of $82.66
(2012$) in MY 2014. So the non-warranty portion of the indirect costs would be $12.32 ($82.66
x 0.149). This value would be added to the learned direct manufacturing cost for each year
through 2022 since the near term markup is considered appropriate for that technology through
2022. Beginning in 2023, when long-term indirect costs begin, the additive factor would become
$10.08 ($82.66 x 0.122). Additionally, the $82.66 cost in 2014 would become $80.18 in MY
2015 due to learning ($82.66 x (1-3 percent)). So, while the warranty portion of the indirect
costs would be $0.49 ($82.66 x 0.006) in 2014, they would decrease to $0.48 ($80.18 x 0.006) in
2015 as warranty costs decrease with learning. The resultant indirect costs for the water pump
would be $12.81 ($12.32+$0.49) in MY 2014 and $12.80 ($12.32+$0.48) in MY2015, and so on
for subsequent years.
Importantly, since the bulk of the indirect costs calculated using this methodology are the
non-warranty costs, and since those costs do not change over with learning, one cannot look at
the ICMs shown in Table 2-118 and assume that our HD pickup and van total costs are, in
general, 1.24 or 1.39 times the direct costs (since most technologies considered for application in
HD pickups and vans are low and medium technologies). This can be illustrated by building on
the example presented above for a water pump on a heavy diesel engine. We already calculated
the MY 2014 total cost as $95.46 (2012$, $82.66+$12.32+$0.49). This is an effective markup of
1.155 ($95.46/$82.66). This is expected since the cost is based in 2014 and the near term ICM is
1.155. In MY2022, the final year of near term markups for this technology, the total cost would
be $80.21 since the learned direct cost has reduced to $67.50, the non-warranty indirect costs
(calculated above) remain $12.32, and the warranty indirect costs have become $0.39
($67.50x0.006). So, in MY2022, we now have an effective markup of 1.19 ($80.21/$67.50).
p We note that the labor portion of warranty repairs does not decrease due to learning. However, we do not have
data to separate this portion and so we apply learning to the entire warranty cost. Because warranty costs are a small
portion of overall indirect costs, this has only a minor impact on the analysis.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-119 Warranty and Non-Warranty Portions of ICMs


SHORT-TERM
LONG-TERM
CLASS
COMPLEXITY
WARRANTY
NON-
WARRANTY
WARRANTY
NON-
WARRANTY
HD Pickup and
Vans
Low
0.012
0.230
0.005
0.187
Medium
0.045
0.343
0.031
0.259
Highl
0.065
0.499
0.032
0.314
High2
0.074
0.696
0.049
0.448
Loose diesel
engines
Low
0.006
0.149
0.003
0.122
Medium
0.022
0.213
0.016
0.165
Highl
0.032
0.249
0.016
0.176
High2
0.037
0.398
0.025
0.265
Loose gasoline
engines
Low
0.012
0.230
0.005
0.187
Medium
0.045
0.343
0.031
0.259
Highl
0.065
0.499
0.032
0.314
High2
0.074
0.696
0.049
0.448
Vocational
Vehicles,
Combination
Tractors and
Trailers
Low
0.013
0.165
0.006
0.134
Medium
0.051
0.252
0.035
0.190
Highl
0.073
0.352
0.037
0.233
High2
0.084
0.486
0.056
0.312
The complexity levels and subsequent ICMs applied throughout this analysis for each
technology are shown in Table 2-120. One notable change since the proposal is to waste heat
recovery which used a short term markup through 2025 in the proposal but uses that markup
through 2027 in this final rule.
Table 2-120 Indirect Cost Markups and Near Term/Long Term Cutoffs Used in this Analysis
TECHNOLOGY
APPLIED TO
ICM
NEAR TERM


COMPLEXITY
THRU
Cylinder head improvements 1
LH/MH/HH Engines
Low
2022
Cylinder head improvements 2
LH/MH/HH Engines
Low
2027
Turbo efficiency improvements 1
LH/MH/HH, HD Pickup & Van Engines
Low
2022
Turbo efficiency improvements 2
LH/MH/HH Engines
Low
2027
EGR cooler efficiency improvements 1
LH/MH/HH Engines
Low
2022
EGR cooler efficiency improvements 2
LH/MH/HH Engines
Low
2027
Water pump improvements 1
LH/MH/HH Engines
Low
2022
Water pump improvements 2
LH/MH/HH Engines
Low
2027
Oil pump improvements 1
LH/MH/HH Engines
Low
2022
Oil pump improvements 2
LH/MH/HH Engines
Low
2027
Fuel pump improvements 1
LH/MH/HH Engines
Low
2022
Fuel pump improvements 2
LH/MH/HH Engines
Low
2027
Fuel rail improvements 1
LH/MH/HH Engines
Low
2022
Fuel rail improvements 2
LH/MH/HH Engines
Low
2027
Fuel injector improvements 1
LH/MH/HH Engines
Low
2022
Fuel injector improvements 2
LH/MH/HH Engines
Low
2027
Piston improvements 1
LH/MH/HH Engines
Low
2022
Piston improvements 2
LH/MH/HH Engines
Low
2027
Valve train friction reductions 1
LH/MH/HH Engines
Low
2022
Valve train friction reductions 2
LH/MH/HH Engines
Low
2027
Turbo compounding 1
LH/MH/HH Engines
Low
2022
Turbo compounding 2
LH/MH/HH Engines
Low
2027
Aftertreatment improvements 1
LH/MH/HH Engines
Low
2022

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Aftertreatment improvements 2
LH/MH/HH Engines
Low
2024
Model based control
LH/MH/HH Engines
Low
2022
Waste heat recovery
HH Engines
Medium
2027
Engine friction reduction 1
HD Pickup & Van Engines
Low
2018
Engine friction reduction 2
HD Pickup & Van Engines
Low
2024
Engine changes to accommodate low friction
lubes
HD Pickup & Van Engines
Low
2018
Variable valve timing - coupled
HD Pickup & Van Engines
Low
2018
Variable valve timing - dual
HD Pickup & Van Engines
Medium
2018
Stoichiometric gasoline direct injection
HD Pickup & Van Engines
Medium
2018
Cylinder deactivation
HD Pickup & Van Engines
Medium
2018
Cooled EGR
HD Pickup & Van Engines
Medium
2024
Turbocharging & downsizing
HD Pickup & Van Engines
Medium
2018
"Right sized" diesel engine
HD Pickup & Van vehicles, Tractors
Low
2022
6 speed transmission
HD Pickup & Van vehicles
Medium
2018
8 speed transmission
HD Pickup & Van vehicles, Vocational
Medium
2018
Automated & Automated manual transmission
(AMT)
Vocational, Tractors
Medium
2022
High efficiency gearbox (HEG)
Vocational, Tractors, HD Pickup &
Vans
Low
2022,2024
Early torque converter lockup (TORQ)
Vocational, HD Pickup & Vans
Low
2022,2018
Auto transmission, power-shift
Tractors
Medium
2022
Dual clutch transmission
Tractors
Medium
2022
Driveline integration
Vocational
Low
2022
6x2 axle
Tractors
Low
2022
Axle disconnect
Vocational
Low
2022
Axle downspeed
Tractors
Low
2022
High efficiency axle
Vocational, Tractors
Low
2022
Lower RR tires 1
HD Pickup & Van vehicles
Low
2018
Lower RR tires 2
HD Pickup & Van vehicles
Low
2024
Low drag brakes
HD Pickup & Van vehicles
Low
2018
Electric power steering
HD Pickup & Van vehicles
Low
2018
High efficiency transmission
HD Pickup & Van vehicles
Low
2024
Driveline friction reduction
HD Pickup & Van vehicles
Low
2022
Improved accessories (electrification)
HD Pickup & Van vehicles
Low
2018
Improved accessories (electrification)
Vocational, Tractors
Low
2022
Lower RR tires 1
Vocational, Tractors, Trailers
Low
2022
Lower RR tires 2
Vocational, Tractors, Trailers
Low
2022
Lower RR tires 3
Vocational, Tractors, Trailers s
Medium
2025
Lower RR tires 4
Vocational, Tractors, Trailers
Medium
2028
Lower RR tires 5
Vocational, Tractors, Trailers
Medium
2031
Automated Tire Inflation System (ATIS)
Tractors, Trailers
Low
2022
Tire Pressure Monitoring System
Vocational, Tractors & Trailers
Low
2022
Aero 1
HD Pickup & Van vehicles
Low
2018
Aero 2
HD Pickup & Van vehicles
Medium
2024
Aero Bins 1 thru 4
Tractors
Low
2022
Aero Bin 5 thru 7
Tractors
Medium
2025
Aero Bins 1 thru 8
Trailers
Low
2018
Weight reduction (via single wide tires and/or
aluminum wheels)
Tractors
Low
2022
Weight reduction via material changes
HD Pickup & Van vehicles
Low
2018
Weight reduction via material changes - 200
lbs, 400 lbs
Vocational
Low
2022
Weight reduction via material changes - 1000
lbs
Vocational
Medium
2022
Weight reduction via material changes
Tractors
Low
2022
Auxiliary power unit (APU), battery APU,
APU with DPF
Tractors
Low
2022

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Fuel operated heater (FOH)
Tractors
Low
2022
Air conditioning leakage
Vocational, Tractors
Low
2022
Air conditioning efficiency
Tractors
Low
2022
Neutral idle
Vocational
Low
2022
Stop-start (no regeneration)
HD Pickup & Van vehicles
Medium
2018
Stop-start (with enhancements)
Vocational
Medium
2022
Auto Engine Shutdown System
Vocational, Tractors
Low
2022
Mild hybrid
HD Pickup & Van vehicles
Highl
2024
Mild hybrid
Vocational
Highl
2025
Strong hybrid
HD Pickup & Van vehicles
Highl
2024
Hybrid without stop-start
Vocational
Highl
2022
Advanced cruise control
Tractors
Low
2022
There is some level of uncertainty surrounding both the ICM and RPE markup factors.
The ICM estimates used in this rule group all technologies into three broad categories and treat
them as if individual technologies within each of the three categories (low, medium, and high
complexity) would have the same ratio of indirect costs to direct costs. This simplification
means it is likely that the direct cost for some technologies within a category will be higher and
some lower than the estimate for the category in general. More importantly, the ICM estimates
have not been validated through a direct accounting of actual indirect costs for individual
technologies. RPEs themselves are inherently difficult to estimate because the accounting
statements of manufacturers do not neatly categorize all cost elements as either direct or indirect
costs. Hence, each researcher developing an RPE estimate must apply a certain amount of
judgment to the allocation of the costs. Moreover, RPEs for heavy- and medium-duty trucks and
for engine manufacturers are not as well studied as they are for the light-duty automobile
industry. Since empirical estimates of ICMs are ultimately derived from the same data used to
measure RPEs, this affects both measures. However, the value of RPE has not been measured
for specific technologies, or for groups of specific technologies. Thus, even if we assume that
the examined technology accurately represents the average impact on all technologies in its
representative category, applying a single average RPE to any given technology by definition
overstates costs for very simple technologies, or understates them for more advanced
technologies in that group.
2.11.1.3 Learning Effects on Technology Costs
For some of the technologies considered in this analysis, manufacturer learning effects
would be expected to play a role in the actual end costs. The "learning curve" or "experience
curve" describes the reduction in unit production costs as a function of accumulated production
volume. In theory, the cost behavior it describes applies to cumulative production volume
measured at the level of an individual manufacturer, although it is often assumed—as both
agencies have done in past regulatory analyses—to apply at the industry-wide level, particularly
in industries that utilize many common technologies and component supply sources. Both
agencies believe there are indeed many factors that cause costs to decrease over time. Research
in the costs of manufacturing has consistently shown that, as manufacturers gain experience in
production, they are able to apply innovations to simplify machining and assembly operations,
use lower cost materials, and reduce the number or complexity of component parts. All of these
factors allow manufacturers to lower the per-unit cost of production (i.e., the manufacturing
learning curve).202

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The agencies have a detailed description of the learning effect in the light-duty 2012-
2016 rulemaking. Most studies of the effect of experience or learning on production costs appear
to assume that cost reductions begin only after some initial volume threshold has been reached,
but not all of these studies specify this threshold volume. The rate at which costs decline beyond
the initial threshold is usually expressed as the percent reduction in average unit cost that results
from each successive doubling of cumulative production volume, sometimes referred to as the
learning rate. Many estimates of experience curves do not specify a cumulative production
volume beyond which cost reductions would no longer occur, instead depending on the
asymptotic behavior of the effect for learning rates below 100 percent to establish a floor on
costs.
In past rulemaking analyses, as noted above, both agencies have used a learning curve
algorithm that applied a learning factor of 20 percent for each doubling of production volume.
NHTSA has used this approach in analyses supporting recent CAFE rules. In its analyses, EPA
has simplified the approach by using an "every two years" based learning progression rather than
a pure production volume progression {i.e., after two years of production it was assumed that
production volumes would have doubled and, therefore, costs would be reduced by 20 percent).
In the light-duty 2012-2016 rulemaking, the agencies employed an additional learning
algorithm to reflect the volume-based learning cost reductions that occur further along on the
learning curve. This additional learning algorithm was termed "time-based" learning simply as a
means of distinguishing this algorithm from the volume-based algorithm mentioned above,
although both of the algorithms reflect the volume-based learning curve supported in the
literature.203 To avoid confusion, we now refer to this learning algorithm as the "flat-portion" of
the learning curve. This way, we maintain the clarity that all learning is, in fact, volume-based
learning, and the level of cost reductions depend only on where on the learning curve a
technology's learning progression is. We distinguish the flat-portion of the curve from the steep-
portion of the curve to indicate the level of learning taking place in the years following
implementation of the technology. The agencies have applied the steep-portion learning
algorithm for those technologies considered to be newer technologies likely to experience rapid
cost reductions through manufacturer learning and the flat-portion learning algorithm for those
technologies considered to be mature technologies likely to experience minor cost reductions
through manufacturer learning. As noted above, the steep-portion learning algorithm results in
20 percent lower costs after two full years of implementation {i.e., the 2016 MY costs are 20
percent lower than the 2014 and 2015 model year costs). Once the steep-portion learning steps
have occurred (for technologies having the steep-portion learning algorithm applied), flat-portion
learning at 3 percent per year becomes effective for 5 years. For technologies having the flat-
portion learning algorithm applied), flat-portion learning at 3 percent per year begins in year 2
and remains effective for 5 years. Beyond 5 years of learning at 3 percent per year, 5 years of
learning at 2 percent per year, then 5 at 1 percent per year become effective. There was no
serious disagreement with this approach in the public comments to any of the GHG/fuel
economy/consumption rulemakings.
Learning effects are applied to most but not all technologies because some of the
expected technologies are already used rather widely in the industry and, presumably, learning
impacts have already occurred. The steep-portion learning algorithm was applied for only a
handful of technologies that are considered to be new or emerging technologies. Most

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
technologies have been considered to be more established given their current use in the fleet and,
hence, the lower flat-portion learning algorithm has been applied. The learning algorithms
applied to each technology are summarized in Table 2-121. One change has been made since the
proposal to waste heat recovery which used learning algorithm 12 in the proposal but uses a new
learning algorithm 14 in this final rule.
Table 2-121 Learning Effect Algorithms Applied to Technologies Used in this Analysis
TECHNOLOGY
APPLIED TO
LEARNING
ALGORITHM
LEARNING
FACTOR
"CURVE" A
Cylinder head improvements 1
LH/MH/HH Engines
Flat
2
Cylinder head improvements 2
LH/MH/HH Engines
Flat
13
Turbo efficiency improvements 1
LH/MH/HH, HD Pickup
& Van Engines
Flat
2
Turbo efficiency improvements 2
LH/MH/HH Engines
Flat
13
EGR cooler efficiency improvements 1
LH/MH/HH Engines
Flat
2
EGR cooler efficiency improvements 2
LH/MH/HH Engines
Flat
13
Water pump improvements 1
LH/MH/HH Engines
Flat
2
Water pump improvements 2
LH/MH/HH Engines
Flat
13
Oil pump improvements 1
LH/MH/HH Engines
Flat
2
Oil pump improvements 2
LH/MH/HH Engines
Flat
13
Fuel pump improvements 1
LH/MH/HH Engines
Flat
2
Fuel pump improvements 2
LH/MH/HH Engines
Flat
13
Fuel rail improvements 1
LH/MH/HH Engines
Flat
2
Fuel rail improvements 2
LH/MH/HH Engines
Flat
13
Fuel injector improvements 1
LH/MH/HH Engines
Flat
2
Fuel injector improvements 2
LH/MH/HH Engines
Flat
13
Piston improvements 1
LH/MH/HH Engines
Flat
2
Piston improvements 2
LH/MH/HH Engines
Flat
13
Valve train friction reductions 1
LH/MH/HH Engines
Flat
2
Valve train friction reductions 2
LH/MH/HH Engines
Flat
13
Turbo compounding 1
LH/MH/HH Engines
Flat
2
Turbo compounding 2
LH/MH/HH Engines
Flat
13
Aftertreatment improvements 1 & 2
LH/MH/HH Engines
Flat
2
Model based control
LH/MH/HH Engines
Flat
13
Waste heat recovery
HH Engines
Steep
14
Engine friction reduction 1 & 2
HD Pickup & Van
Engines
None
1
Engine changes to accommodate low
friction lubes
HD Pickup & Van
Engines
None
1
Variable valve timing
HD Pickup & Van
Engines
Flat
8
Stoichiometric gasoline direct injection
HD Pickup & Van
Engines
Flat
7
Cylinder deactivation
HD Pickup & Van
Engines
Flat
8
Cooled EGR
HD Pickup & Van
Engines
Flat
7
Turbocharging & downsizing
HD Pickup & Van
Engines
Flat
7
"Right sized" diesel engine
HD Pickup & Van
vehicles, Tractors
None
1

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
6 speed transmission
HD Pickup & Van
vehicles
Flat
7
8 speed transmission
HD Pickup & Van
vehicles, Vocational
Flat
7
Automated & Automated manual
transmission (AMT)
Vocational, Tractors
Flat
12
High efficiency gearbox (HEG)
Vocational, Tractors, HD
Pickup & Vans
Flat
13,6
Early torque converter lockup (TORQ)
Vocational, HD Pickup &
Vans
Flat
13, 8
Auto transmission, power-shift
Tractors
Flat
12
Dual clutch transmission
Tractors
Flat
12
Driveline integration
Vocational
Flat
13
6x2 axle
Tractors
Flat
12
Axle disconnect
Vocational
None
1
Axle downspeed
Tractors
Flat
12
High efficiency axle
Vocational, Tractors
Flat
12
Lower RR tires 1
HD Pickup & Van
vehicles
None
1
Lower RR tires 2
HD Pickup & Van
vehicles
Steep
11
Low drag brakes
HD Pickup & Van
vehicles
None
1
Electric power steering
HD Pickup & Van
vehicles
Flat
8
High efficiency transmission
HD Pickup & Van
vehicles
Flat
6
Driveline friction reduction
HD Pickup & Van
vehicles
Flat
3
Improved accessories (electrification)
HD Pickup & Van
vehicles
Flat
8
Improved accessories
Tractors
Flat
12
Improved fan
Tractors
Flat
12
Lower RR tires 1
Vocational, Tractors,
Trailers
Flat
2
Lower RR tires 2
Vocational, Tractors,
Trailers
Flat
2
Lower RR tires 3
Vocational, Tractors,
Trailers
Flat
12
Lower RR tires 4
Vocational, Tractors,
Trailers
Flat
13
Lower RR tires 5
Vocational, Tractors,
Trailers

13
Automated Tire Inflation System (ATIS)
Tractors, Trailers
Flat
12
Tire Pressure Monitoring System (TPMS)
Vocational, Tractors,
Trailers
Flat
12
Aero 1 & 2
HD Pickup & Van
vehicles
Flat
8
Aero Bins 1 & 2
Tractors
None
1
Aero Bin 3
Tractors
Flat
2
Aero Bins 4 thru 7
Tractors
Steep
4
Aero Bins 1 thru 8
Trailers
Flat
2
Weight reduction (via single wide tires
and/or aluminum wheels)
Tractors
Flat
2

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Weight reduction via material changes
HD Pickup & Van
vehicles
Flat
6
Weight reduction via material changes
Vocational, Tractors
Flat
13
Auxiliary power unit (APU), battery
APU, APU with DPF
Tractors
Flat
2
Fuel operated heater (FOH)
Tractors
Flat
2
Air conditioning leakage
Vocational, Tractors
Flat
2
Air conditioning efficiency
Tractors
Flat
12
Neutral idle
Vocational
None
1
Stop-start (no regeneration)
HD Pickup & Van
vehicles
Steep
9
Stop-start (with enhancements)
Vocational
Flat
13
Mild hybrid
HD Pickup & Van
vehicles
Flat
6
Mild hybrid
Tractors
Flat
12
Strong hybrid
HD Pickup & Van
vehicles
Steep
11
Hybrid without stop-start
Vocational
Steep
11
Advanced cruise control
Tractors
Flat
12
Note:
" See table and figure below.
The actual year-by-year factors for the numbered curves shown in Table 2-121 are shown
in Table 2-122 and are shown graphically in Figure 2-84.
Table 2-122 Year-by-year Learning Curve Factors for the Learning Curves Used in this Analysis
CURVEA
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
1
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
2
1.000
0.970
0.941
0.913
0.885
0.868
0.850
0.833
0.817
0.800
0.784
0.769
0.761
0.753
3
1.031
1.000
0.970
0.941
0.913
0.894
0.877
0.859
0.842
0.825
0.808
0.792
0.784
0.777
4
1.000
1.000
0.800
0.800
0.640
0.621
0.602
0.584
0.567
0.550
0.533
0.517
0.507
0.497
6
1.096
1.063
1.031
1.000
0.970
0.941
0.913
0.885
0.859
0.842
0.825
0.808
0.792
0.776
7
0.941
0.913
0.885
0.868
0.850
0.833
0.817
0.800
0.784
0.769
0.753
0.738
0.731
0.723
8
1.031
1.000
0.970
0.951
0.932
0.913
0.895
0.877
0.859
0.842
0.825
0.809
0.801
0.793
9
1.250
1.000
1.000
0.970
0.941
0.913
0.885
0.859
0.833
0.808
0.784
0.760
0.745
0.730
11
1.563
1.563
1.563
1.563
1.563
1.250
1.250
1.000
0.970
0.941
0.913
0.885
0.859
0.842
12
1.130
1.096
1.063
1.031
1.000
0.970
0.941
0.913
0.894
0.877
0.859
0.842
0.825
0.808
13
1.238
1.201
1.165
1.130
1.096
1.063
1.031
1.000
0.970
0.941
0.913
0.894
0.877
0.859
14
1.563
1.563
1.563
1.563
1.563
1.250
1.250
1.000
1.000
0.800
0.800
0.640
0.621
0.602
Note:
" Curves 5 and 10 were generated but subsequently not used so are not included in the table.

-------
*** E.O. 12866 Review — Revised —Do Not Cite, Quote, or Release During Review ***
1.60
1.40
1.20
1.00
0.80
0.60
0.40
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
Figure 2-84 Year-by-year Learning Curve Factors for the Learning Curves used in this Analysis
Importantly, where the factors shown in Table 2-122 and, therefore, the curves shown in
Figure 2-84 equal "1.00" represents the year for which any particular technology's cost is based.
In other words, for example, the cost estimate that we have for cylinder head improvements 2 is
"based" in 2021 (curve 13). Therefore, its learning factor equals 1.00 in 2021 and then decreases
going forward to represent lower costs due to learning effects. Its learning factors are greater
than 1.00 in years before 2021 to represent "reverse" learning, i.e., higher costs than our 2021
estimate since production volumes have, presumably, not yet reached the point where our cost
estimate can be considered valid.
2.11.1.4 Technology Penetration Rates and Package Costs
Determining the stringency of the standards involves a balancing of relevant factors -
chiefly technology feasibility and effectiveness, costs, and lead time. For each of the standards,
the agencies have projected a technology path to achieve the standards reflecting an application
rate of those technologies the agencies consider to be available at reasonable cost in the lead
times provided. The agencies do not expect each of the technologies for which costs have been
developed to be employed by all engines and vehicles across the board. Further, many of today's
vehicles are already equipped with some of the technologies and/or are expected to adopt them
by MY2018 to comply with the HD Phase 1 standards. Estimated penetration rates in both the
reference and control cases are necessary for each vehicle category. The penetration rates for

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
many technologies are zero in the reference case; however, for some technologies—notably aero
and tire technologies—the reference case penetration rate is not always zero. These reference
and control case penetration rates are then applied to the technology costs with the result being a
package cost for each vehicle category. As such, package costs are rarely if ever a simple sum of
all the technology costs since each technology would be expected to be adopted at different rates.
For HD pickups and vans, the CAFE model predicts the technology penetration rates that
most cost effectively meet the standards being adopted. Similar to vocational vehicles, tractors
and trailers, package costs are rarely if ever a simple sum of all the technology costs since each
technology would be expected to be adopted at different rates. The methods for estimating
technology penetration rates and resultant costs (and other impacts) for HD pickups and vans are
discussed in Chapter 10 of this RIA.
2.11.1.5 Conversion of Technology Costs to 2013 U.S. Dollars
As noted above in Section IX C. 1, the agencies are using technology costs from many
different sources. These sources, having been published in different years, present costs in
different year dollars (i.e., 2009 dollars or 2010 dollars). For this analysis, the agencies sought to
have all costs in terms of 2013 dollars to be consistent with the dollars used by AEO in its 2015
Annual Energy Outlook.204 While the factors used to convert from 2009 dollars (or other) to
2013 dollars are small, the agencies prefer to be overly diligent in this regard to ensure
consistency across our benefit-cost analysis. The agencies have used the GDP Implicit Price
Deflator for Gross Domestic Product as the converter, with the actual factors used as shown in
Table 2-123.205
Table 2-123 Implicit Price Deflators and Conversion Factors for Conversion to 2013$
CALENDAR YEAR
2005
2006
2007
2008
2009
2010
2011
2012
2013
Price index for GDP
91.988
94.814
97.337
99.246
100
101.221
103.311
105.214
106.929
Factor applied for
2013$
1.162
1.128
1.099
1.077
1.069
1.056
1.035
1.016
1.000
The sections above describe the technologies expected to be used to enable compliance
with the standards and the penetration rates we estimate to be possible. Here we present the cost
of each technology, the markups used for each, the learning effect applied, etc. The tables here
present the direct manufacturing cost (DMC) we have estimated for each technology, the indirect
costs (IC) associated with that technology, and the resultant total cost (TC) of each (where
TC=DMC+IC). Each table also presents, where appropriate, the expected adoption rate of each
technology in both the reference case (i.e., alternative la or the "no new controls" case) and the
policy case (the standards). For most technologies, the reference case adoption rate will be
shown as 0 percent (or blanks in the tables) since the Phase 2 technologies are expected to be in
limited or no use in the regulatory timeframe. However, for some technologies—notably tire and
aero technologies—there is expected to considerably adoption of Phase 2 technologies in the
reference case. The final row(s) of the tables shown here include the penetration rates applied to
the technology costs to arrive at a total cost of each technology as it is applied to the ultimate
package (noted as TCp). In Chapter 2.12 of this RIA, we sum these costs (the TCp costs) into
total cost applied to the packages presented later in Chapter 7 of this RIA. We also describe how
we moved from the total cost applied to the packages developed for the regulatory classes (i.e.,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Class 8 Sleeper cab, LH vocational medium-speed, etc.) to the MOVES sourcetypes (i.e., transit
bus, refuse truck, combination long haul, etc.) in order to develop program costs. This final
step—moving from regulatory classes to MOVES sourcetypes, was necessary because MOVES
populations, sales, inventory calculations, etc., are based on sourcetypes, not regulatory classes,
and to allow for a more granular look at payback as presented in Chapter 7.2.4 of this RIA.
Note that the text surrounding the tables presented here refer to low/medium/high
complexity ICMs and to learning curves used. We discuss both the ICMs and the learning
effects used in this analysis in Chapter 2.11.1.2 and 2.11.1.3 of this RIA, respectively.
We received some comments on our technology costs, both direct and indirect costs, and
on learning impacts. We address those comments in Section 11.3 of the Response to Comments
document.
2.11.2 Costs of Engine Technologies
2.11.2.1 Aftertreatment Improvements
We have estimated the cost of aftertreatment improvements based on the aftertreatment
improvements technology discussed in the Phase 1 rules. That technology was estimated at $25
(DMC, 2008$, in 2014) for each percentage improvement in fuel consumption, or $100 (DMC,
2008$, in 2014) for the 4 percent improvement expected as a result of that program. In Phase 2,
we are expecting only a 0.6 percent improvement in fuel consumption resulting from
aftertreatment improvements. Therefore, the cost in Phase 2 including updates to 2013$ is $16
(DMC, 2013$, in 2014). We consider this technology to be on the flat portion of the learning
curve (curve 2) and have applied a low complexity ICM with short term markups through 2024.
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-124 Costs of Aftertreatment Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aftertreatment
improvements - level 2
DMC
$14
$14
$14
$13
$13
$13
$13
$12
$12
$12
Aftertreatment
improvements - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Aftertreatment
improvements - level 2
TC
$17
$17
$16
$16
$16
$15
$15
$15
$15
$15
Aftertreatment
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aftertreatment
improvements - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Aftertreatment
improvements - level 2
TCp
$0
$0
$0
$8
$8
$8
$14
$13
$13
$15
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-125 Costs of Aftertreatment Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aftertreatment
improvements - level 2
DMC
$14
$14
$14
$13
$13
$13
$13
$12
$12
$12
Aftertreatment
improvements - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Aftertreatment
improvements - level 2
TC
$17
$17
$16
$16
$16
$15
$15
$15
$15
$15
Aftertreatment
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aftertreatment
improvements - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Aftertreatment
improvements - level 2
TCp
$0
$0
$0
$7
$7
$7
$14
$14
$14
$15
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.2 Cylinder Head Improvements
We have estimated the cost of cylinder head improvements based on the cylinder head
improvements technology discussed in the Phase 1 rules. That technology was estimated at $9
(DMC, 2008$, in 2014) for light HDD engines and at $5 (DMC, 2008$, in 2014) for medium and
heavy HDD engines. In Phase 2, we are estimating equivalent costs for an additional level of
cylinder head improvements. With updates to 2013$, we estimate the costs at $10 (DMC,
2013$, in 2021) for light HDD engines and at $6 (DMC, 2013$, in 2021) for medium and heavy
HDD engines. We consider this technology to be on the flat portion of the learning curve (curve
13) and have applied a low complexity ICM with short term markups through 2027. The
resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-126 Costs for Cylinder Head Improvements - Level 2
Light HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Cylinder head
improvements - level 2
DMC
$11
$11
$10
$10
$10
$10
$9
$9
$9
$9
Cylinder head
improvements - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Cylinder head
improvements - level 2
TC
$13
$12
$12
$12
$11
$11
$11
$11
$10
$10
Cylinder head
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Cylinder head
improvements - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Cylinder head
improvements - level 2
TCp
$0
$0
$0
$6
$6
$6
$10
$10
$9
$10
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-127 Costs for Cylinder Head Improvements - Level 2
Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Cylinder head
improvements - level 2
DMC
$6
$6
$6
$6
$6
$6
$5
$5
$5
$5
Cylinder head
improvements - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Cylinder head
improvements - level 2
TC
$7
$7
$7
$7
$7
$6
$6
$6
$6
$6
Cylinder head
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Cylinder head
improvements - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Cylinder head
improvements - level 2
TCp
$0
$0
$0
$3
$3
$3
$6
$6
$5
$6
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-128 Costs for Cylinder Head Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Cylinder head
improvements - level 2
DMC
$6
$6
$6
$6
$6
$6
$5
$5
$5
$5
Cylinder head
improvements - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Cylinder head
improvements - level 2
TC
$7
$7
$7
$7
$7
$6
$6
$6
$6
$6
Cylinder head
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Cylinder head
improvements - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Cylinder head
improvements - level 2
TCp
$0
$0
$0
$3
$3
$3
$6
$6
$6
$6
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.3 Turbocharger Efficiency Improvements
We have estimated the cost of turbo efficiency improvements based on the turbo
efficiency improvements technology discussed in the Phase 1 rules. That technology was
estimated at $16 (DMC, 2008$, in 2014) for all HDD engines. In Phase 2, we are estimating
equivalent costs for an additional level of turbo efficiency improvements. With updates to
2013$, we estimate the costs at $17 (DMC, 2013$, in 2021) for all HDD engines. We consider
this technology to be on the flat portion of the learning curve (curve 13) and have applied a low
complexity ICM with short term markups through 2027. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-129 Costs for Turbocharger Efficiency Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Turbo efficiency
improvements - level 2
DMC
$18
$18
$17
$17
$16
$16
$15
$15
$15
$14
Turbo efficiency
improvements - level 2
IC
$3
$3
$3
$3
$3
$3
$3
$3
$3
$3
Turbo efficiency
improvements - level 2
TC
$21
$21
$20
$19
$19
$18
$18
$18
$17
$17
Turbo efficiency
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Turbo efficiency
improvements - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Turbo efficiency
improvements - level 2
TCp
$0
$0
$0
$10
$9
$9
$16
$16
$16
$17
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-130 Costs for Turbocharger Efficiency Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Turbo efficiency
improvements - level 2
DMC
$18
$18
$17
$17
$16
$16
$15
$15
$15
$14
Turbo efficiency
improvements - level 2
IC
$3
$3
$3
$3
$3
$3
$3
$3
$3
$3
Turbo efficiency
improvements - level 2
TC
$21
$21
$20
$19
$19
$18
$18
$18
$17
$17
Turbo efficiency
improvements - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Turbo efficiency
improvements - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Turbo efficiency
improvements - level 2
TCp
$0
$0
$0
$9
$9
$8
$17
$17
$16
$17
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
For HD diesel pickups and vans, we are estimating use of the Phase 1 level of turbo
efficiency improvements, or $17 (DMC, 2012$, in 2014). We consider this technology to be on
the flat portion of the learning curve (curve 2) and have applied a low complexity ICM with
short term markups through 2022. The resultant technology costs are shown below.
Table 2-131 Costs for Turbocharger Efficiency Improvements - Level 1
HD Pickups & Vans (2012$)
TECHNOLOGY

2021
2022
2023
2024
2025
2026
2027
Turbo efficiency improvements - level 1
DMC
$14
$14
$13
$13
$13
$13
$12
Turbo efficiency improvements - level 1
IC
$3
$3
$2
$2
$2
$2
$2
Turbo efficiency improvements - level 1
TC
$16
$16
$15
$15
$15
$15
$15
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.2.4 Turbo Compounding
We have estimated the cost of turbo compounding based on the turbo compounding
technology discussed in the Phase 1 rules. That technology was estimated at $813 (DMC,
2008$, in 2014) for all HDD tractor engines. In Phase 2, we are estimating equivalent costs for
an additional level of turbo compounding improvements. With updates to 2013$, we estimate
the costs at $875 (DMC, 2013$, in 2021) for all HDD tractor engines. We consider this
technology to be on the flat portion of the learning curve (curve 13) and have applied a low
complexity ICM with short term markups through 2027. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-132 Costs for Turbocharger Compounding - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Turbo compounding
- level 2
DMC
$959
$930
$902
$875
$849
$824
$799
$783
$767
$752
Turbo compounding
- level 2
IC
$136
$136
$136
$136
$135
$135
$135
$135
$135
$135
Turbo compounding
- level 2
TC
$1,095
$1,066
$1,038
$1,011
$985
$959
$934
$918
$902
$887
Turbo compounding
- level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Turbo compounding
- level 2
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
10%
Turbo compounding
- level 2
TCp
$0
$0
$0
$51
$49
$48
$93
$92
$90
$89
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.5 Valve Actuation
We have estimated the cost of valve actuation based on the dual cam phasing cost
estimate used in the 2017-2025 light-duty rule. In that analysis, we estimated costs at $151
(DMC, 2010$, in 2015) for a large V8 engine. In this HD Phase 2 program, we are estimating
equivalent costs for this technology. With updates to 2013$, we estimate the costs at $160
(DMC, 2013$, in 2015) for all HDD engines. We consider this technology to be on the flat
portion of the learning curve (curve 8) and have applied a medium complexity ICM with short
term markups through 2018. The resultant technology costs, penetration rates and total cost
applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-133 Costs for Valve Actuation
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Valve actuation
DMC
$149
$146
$143
$140
$137
$135
$132
$129
$128
$127
Valve actuation
IC
$61
$46
$46
$46
$46
$46
$45
$45
$45
$45
Valve actuation
TC
$210
$192
$189
$186
$183
$180
$177
$175
$173
$172
Valve actuation
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Valve actuation
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Valve actuation
All
$0
$0
$0
$93
$92
$90
$160
$157
$156
$172
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-134 Costs for Valve Actuation
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Valve actuation
DMC
$149
$146
$143
$140
$137
$135
$132
$129
$128
$127
Valve actuation
IC
$61
$46
$46
$46
$46
$46
$45
$45
$45
$45
Valve actuation
TC
$210
$192
$189
$186
$183
$180
$177
$175
$173
$172
Valve actuation
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Valve actuation
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Valve actuation
All
$0
$0
$0
$84
$82
$81
$169
$166
$165
$172
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
For HD pickups and vans, we have estimated the costs of dual cam phasing based on the
DMC, IC and TC presented above in Table 2-133.
For discrete variable valve lift (DVVL), we have again used the 2017-2025 light-duty
FRM values updated to 2012$ to arrive at a cost of $259 (DMC, 2012$, in 2015). We consider
this technology to be on the flat portion of the learning curve (curve 8) and have applied medium
complexity markups with short term markups through 2024. The resultant costs are presented
below.
Table 2-135 Costs for Discrete Variable Valve Lift (DWL)
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Discrete variable
valve lift (DWL)
DMC
$227
$223
$218
$214
$210
$207
$205
Discrete variable
valve lift (DWL)
IC
$74
$74
$74
$74
$74
$73
$73
Discrete variable
valve lift (DWL)
TC
$301
$297
$292
$288
$283
$281
$279
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.2.6 EGR
We have estimated the cost of EGR cooler improvements based on the EGR cooler
improvements technology discussed in the Phase 1 rules. That technology was estimated at $3

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
(DMC, 2008$, in 2014) for all HDD engines. In Phase 2, we are estimating equivalent costs for
an additional level of EGR cooler improvements. With updates to 2013$, we estimate the costs
at $3 (DMC, 2013$, in 2021) for all HDD engines. We consider this technology to be on the flat
portion of the learning curve (curve 13) and have applied a low complexity ICM with short term
markups through 2027. The resultant technology costs, penetration rates and total cost applied to
the package are shown below.
Table 2-136 Costs for EGR Cooler Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
EGR cooler - level 2
DMC
$4
$4
$3
$3
$3
$3
$3
$3
$3
$3
EGR cooler - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
EGR cooler - level 2
TC
$4
$4
$4
$4
$4
$4
$4
$4
$3
$3
EGR cooler - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
EGR cooler - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
EGR cooler - level 2
TCp
$0
$0
$0
$2
$2
$2
$3
$3
$3
$3
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-137 Costs for EGR Cooler Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
EGR cooler - level 2
DMC
$4
$4
$3
$3
$3
$3
$3
$3
$3
$3
EGR cooler - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
EGR cooler - level 2
TC
$4
$4
$4
$4
$4
$4
$4
$4
$3
$3
EGR cooler - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
EGR cooler - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
EGR cooler - level 2
TCp
$0
$0
$0
$2
$2
$2
$3
$3
$3
$3
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
For HD pickups and vans, we have estimated the costs of adding cooled EGR to a
gasoline engine based on the values used in the 2017-2025 light-duty FRM. We have scaled
upward the light-duty value by 25 percent and converted to 2012$ to arrive at a cost of $317
(DMC, 2012$, in 2012). We consider this technology to be on the flat portion of the learning
curve (curve 7) and have applied medium complexity markups with near term markups through
2024. The resultant costs are presented below.
Table 2-138 Costs for Cooled EGR
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Cooled EGR
DMC
$253
$248
$243
$239
$234
$231
$229
Cooled EGR
IC
$120
$120
$119
$119
$89
$89
$89
Cooled EGR
TC
$373
$368
$363
$358
$323
$321
$318
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.2.7 Water Pump Improvements
We have estimated the cost of water pump improvements based on the water pump
improvements technology discussed in the Phase 1 rules. That technology was estimated at $78
(DMC, 2008$, in 2014) for all HDD engines. In Phase 2, we are estimating equivalent costs for
an additional level of water pump improvements. With updates to 2013$, we estimate the costs
at $84 (DMC, 2013$, in 2021) for all HDD engines. We consider this technology to be on the
flat portion of the learning curve (curve 13) and have applied a low complexity ICM with short
term markups through 2027. The resultant technology costs, penetration rates and total cost
applied to the package are shown below.
Table 2-139 Costs for Water Pump Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Water pump - level 2
DMC
$92
$89
$87
$84
$82
$79
$77
$75
$74
$72
Water pump - level 2
IC
$13
$13
$13
$13
$13
$13
$13
$13
$13
$13
Water pump - level 2
TC
$105
$103
$100
$97
$95
$92
$90
$88
$87
$85
Water pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Water pump - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Water pump - level 2
TCp
$0
$0
$0
$58
$57
$55
$81
$79
$78
$85
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-140 Costs for Water Pump Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Water pump - level 2
DMC
$92
$89
$87
$84
$82
$79
$77
$75
$74
$72
Water pump - level 2
IC
$13
$13
$13
$13
$13
$13
$13
$13
$13
$13
Water pump - level 2
TC
$105
$103
$100
$97
$95
$92
$90
$88
$87
$85
Water pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Water pump - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Water pump - level 2
TCp
$0
$0
$0
$44
$43
$41
$85
$84
$82
$85
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.8 Oil Pump Improvements
We have estimated the cost of oil pump improvements based on the oil pump
improvements technology discussed in the Phase 1 rules. That technology was estimated at just
under $4 (DMC, 2008$, in 2014) for all HDD engines. In Phase 2, we are estimating equivalent
costs for an additional level of oil pump improvements. With updates to 2013$, we estimate the
costs at just over $4 (DMC, 2013$, in 2021) for all HDD engines. We consider this technology
to be on the flat portion of the learning curve (curve 13) and have applied a low complexity ICM
with short term markups through 2027. The resultant technology costs, penetration rates and
total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-141 Costs for Oil Pump Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Oil pump - level 2
DMC
$5
$4
$4
$4
$4
$4
$4
$4
$4
$4
Oil pump - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Oil pump - level 2
TC
$5
$5
$5
$5
$5
$5
$4
$4
$4
$4
Oil pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Oil pump - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Oil pump - level 2
TCp
$0
$0
$0
$3
$3
$3
$4
$4
$4
$4
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-142 Costs for Oil Pump Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Oil pump - level 2
DMC
$5
$4
$4
$4
$4
$4
$4
$4
$4
$4
Oil pump - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Oil pump - level 2
TC
$5
$5
$5
$5
$5
$5
$4
$4
$4
$4
Oil pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Oil pump - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Oil pump - level 2
TCp
$0
$0
$0
$2
$2
$2
$4
$4
$4
$4
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.9 Fuel Pump Improvements
We have estimated the cost of fuel pump improvements based on the fuel pump
improvements technology discussed in the Phase 1 rules. That technology was estimated at just
under $4 (DMC, 2008$, in 2014) for all HDD engines. In Phase 2, we are estimating equivalent
costs for an additional level of fuel pump improvements. With updates to 2013$, we estimate the
costs at just over $4 (DMC, 2013$, in 2021) for all HDD engines. We consider this technology
to be on the flat portion of the learning curve (curve 13) and have applied a low complexity ICM
with short term markups through 2027. The resultant technology costs, penetration rates and
total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-143 Costs for Fuel Pump Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel pump - level 2
DMC
$5
$4
$4
$4
$4
$4
$4
$4
$4
$4
Fuel pump - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Fuel pump - level 2
TC
$5
$5
$5
$5
$5
$5
$4
$4
$4
$4
Fuel pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel pump - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Fuel pump - level 2
TCp
$0
$0
$0
$3
$3
$3
$4
$4
$4
$4
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-144 Costs for Fuel Pump Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel pump - level 2
DMC
$5
$4
$4
$4
$4
$4
$4
$4
$4
$4
Fuel pump - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Fuel pump - level 2
TC
$5
$5
$5
$5
$5
$5
$4
$4
$4
$4
Fuel pump - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel pump - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Fuel pump - level 2
TCp
$0
$0
$0
$2
$2
$2
$4
$4
$4
$4
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.10 Fuel Rail Improvements
We have estimated the cost of fuel rail improvements based on the fuel rail improvements
technology discussed in the Phase 1 rules. That technology was estimated at $10 (DMC, 2008$,
in 2014) for LHDD engines and just under $9 (DMC, 2008$, in 2014) for MHDD and HHDD
engines. In Phase 2, we are estimating equivalent costs for an additional level of fuel rail
improvements. With updates to 2013$, we estimate the costs at $11 (DMC, 2013$, in 2021) for
LHDD and at just over $9 (DMC, 2013$, in 2021) for MHDD and HHDD engines. We consider
this technology to be on the flat portion of the learning curve (curve 13) and have applied a low
complexity ICM with short term markups through 2027. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-145 Costs for Fuel Rail Improvements - Level 2
Light HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel rail - level 2
DMC
$12
$12
$11
$11
$11
$10
$10
$10
$10
$9
Fuel rail - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Fuel rail - level 2
TC
$14
$13
$13
$13
$12
$12
$12
$11
$11
$11
Fuel rail - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel rail - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Fuel rail - level 2
TCp
$0
$0
$0
$8
$7
$7
$11
$10
$10
$11
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-146 Costs for Fuel Rail Improvements - Level 2
Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel rail - level 2
DMC
$10
$10
$10
$9
$9
$9
$8
$8
$8
$8
Fuel rail - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Fuel rail - level 2
TC
$12
$11
$11
$11
$10
$10
$10
$10
$10
$9
Fuel rail - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel rail - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Fuel rail - level 2
TCp
$0
$0
$0
$6
$6
$6
$9
$9
$9
$9
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-147 Costs for Fuel Rail Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel rail - level 2
DMC
$10
$10
$10
$9
$9
$9
$8
$8
$8
$8
Fuel rail - level 2
IC
$1
$1
$1
$1
$1
$1
$1
$1
$1
$1
Fuel rail - level 2
TC
$12
$11
$11
$11
$10
$10
$10
$10
$10
$9
Fuel rail - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel rail - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Fuel rail - level 2
TCp
$0
$0
$0
$5
$5
$5
$9
$9
$9
$9
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.11 Fuel Injector Improvements
We have estimated the cost of fuel injector improvements based on the fuel injector
improvements technology discussed in the Phase 1 rules. That technology was estimated at $13
(DMC, 2008$, in 2014) for LHDD engines and $9 (DMC, 2008$, in 2014) for MHDD and
HHDD engines. In Phase 2, we are estimating equivalent costs for an additional level of fuel
injector improvements. With updates to 2013$, we estimate the costs at $13 (DMC, 2012$, in
2021) for LHDD and at $10 (DMC, 2013$, in 2021) for MHDD and HHDD engines. We
consider this technology to be on the flat portion of the learning curve (curve 13) and have
applied a low complexity ICM with short term markups through 2027. The resultant technology
costs, penetration rates and total cost applied to the package are shown below.
Table 2-148 Costs for Fuel Injector Improvements - Level 2
Light HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel injectors - level 2
DMC
$15
$14
$14
$13
$13
$13
$12
$12
$12
$12
Fuel injectors - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Fuel injectors - level 2
TC
$17
$16
$16
$16
$15
$15
$14
$14
$14
$14
Fuel injectors - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel injectors - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Fuel injectors - level 2
TCp
$0
$0
$0
$8
$8
$7
$13
$13
$12
$14
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-149 Costs for Fuel Injector Improvements - Level 2
Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel injectors - level 2
DMC
$11
$11
$10
$10
$10
$10
$9
$9
$9
$9
Fuel injectors - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Fuel injectors - level 2
TC
$13
$12
$12
$12
$11
$11
$11
$11
$10
$10
Fuel injectors - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel injectors - level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Fuel injectors - level 2
TCp
$0
$0
$0
$6
$6
$6
$10
$10
$9
$10
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-150 Costs for Fuel Injector Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Fuel injectors - level 2
DMC
$11
$11
$10
$10
$10
$10
$9
$9
$9
$9
Fuel injectors - level 2
IC
$2
$2
$2
$2
$2
$2
$2
$2
$2
$2
Fuel injectors - level 2
TC
$13
$12
$12
$12
$11
$11
$11
$11
$10
$10
Fuel injectors - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Fuel injectors - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Fuel injectors - level 2
TCp
$0
$0
$0
$5
$5
$5
$10
$10
$10
$10
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.12 Piston Improvements
We have estimated the cost of piston improvements based on the piston improvements
technology discussed in the Phase 1 rules. That technology was estimated at just over $2 (DMC,
2008$, in 2014) for all HDD engines. In Phase 2, we are estimating equivalent costs for an
additional level of fuel pump improvements. With updates to 2013$, we estimate the costs at $3
(DMC, 2013$, in 2021) for all HDD engines. We consider this technology to be on the flat
portion of the learning curve (curve 13) and have applied a low complexity ICM with short term
markups through 2027. The resultant technology costs, penetration rates and total cost applied to
the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-151 Costs for Piston Improvements - Level 2
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Piston improvements -
level 2
DMC
$3
$3
$3
$3
$2
$2
$2
$2
$2
$2
Piston improvements -
level 2
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Piston improvements -
level 2
TC
$3
$3
$3
$3
$3
$3
$3
$3
$3
$3
Piston improvements -
level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Piston improvements -
level 2
Alt 3
0%
0%
0%
50%
50%
50%
90%
90%
90%
100%
Piston improvements -
level 2
TCp
$0
$0
$0
$1
$1
$1
$2
$2
$2
$3
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-152 Costs for Piston Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Piston improvements -
level 2
DMC
$3
$3
$3
$3
$2
$2
$2
$2
$2
$2
Piston improvements -
level 2
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Piston improvements -
level 2
TC
$3
$3
$3
$3
$3
$3
$3
$3
$3
$3
Piston improvements -
level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Piston improvements -
level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Piston improvements -
level 2
TCp
$0
$0
$0
$1
$1
$1
$3
$3
$2
$3
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.13 Valvetrain Friction Reduction
We have estimated the cost of valvetrain friction reduction based on the valvetrain
friction reduction technology discussed in the Phase 1 rules. That technology was estimated at
$94 (DMC, 2008$, in 2014) for LHDD engines and $70 (DMC, 2008$, in 2014) for MHDD and
HHDD engines. In Phase 2, we are estimating equivalent costs for an additional level of fuel
injector improvements. With updates to 2013$, we estimate the costs at $101 (DMC, 2013$, in
2021) for LHDD and at $76 (DMC, 2013$, in 2021) for MHDD and HHDD engines. We
consider this technology to be on the flat portion of the learning curve (curve 13) and have
applied a low complexity ICM with short term markups through 2027. The resultant technology
costs, penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-153 Costs for Valvetrain Friction Improvements - Level 2
Light HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Valvetrain friction
reduction - level 2
DMC
$111
$107
$104
$101
$98
$95
$92
$90
$89
$87
Valvetrain friction
reduction - level 2
IC
$16
$16
$16
$16
$16
$16
$16
$16
$16
$16
Valvetrain friction
reduction - level 2
TC
$126
$123
$120
$117
$114
$111
$108
$106
$104
$102
Valvetrain friction
reduction - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Valvetrain friction
reduction - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Valvetrain friction
reduction - level 2
TCp
$0
$0
$0
$70
$68
$66
$97
$95
$94
$102
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-154 Costs for Valvetrain Friction Improvements - Level 2
Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Valvetrain friction
reduction - level 2
DMC
$83
$81
$78
$76
$73
$71
$69
$68
$66
$65
Valvetrain friction
reduction - level 2
IC
$12
$12
$12
$12
$12
$12
$12
$12
$12
$12
Valvetrain friction
reduction - level 2
TC
$95
$92
$90
$87
$85
$83
$81
$79
$78
$77
Valvetrain friction
reduction - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Valvetrain friction
reduction - level 2
Alt 3
0%
0%
0%
60%
60%
60%
90%
90%
90%
100%
Valvetrain friction
reduction - level 2
TCp
$0
$0
$0
$52
$51
$50
$73
$71
$70
$77
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-155 Costs for Valvetrain Friction Improvements - Level 2
HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Valvetrain friction
reduction - level 2
DMC
$83
$81
$78
$76
$73
$71
$69
$68
$66
$65
Valvetrain friction
reduction - level 2
IC
$12
$12
$12
$12
$12
$12
$12
$12
$12
$12
Valvetrain friction
reduction - level 2
TC
$95
$92
$90
$87
$85
$83
$81
$79
$78
$77
Valvetrain friction
reduction - level 2
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Valvetrain friction
reduction - level 2
Alt 3
0%
0%
0%
45%
45%
45%
95%
95%
95%
100%
Valvetrain friction
reduction - level 2
TCp
$0
$0
$0
$39
$38
$37
$77
$75
$74
$77
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.14 "Right-sized" Diesel Engine
We have estimated the cost of a slightly smaller diesel engine at a $500 savings (DMC,
2013$, in any year) for all HDD tractor engines. We believe this represents an opportunity for
lower costs because smaller diesel engines contain less materials and are, generally, less costly to
produce than a larger diesel engine. As this cost is considered applicable in any year, we have
not applied learning effects (curve 1). We have applied a low complexity ICM with short term
markups through 2022. The resultant technology costs, penetration rates and total cost applied to
the package are shown below. For HD pickups and vans, we estimated the right-sized diesel
engine cost as cost neutral to any reference case diesel engine and limited the technology to
diesel vans. We have not included any costs associated with lost utility of the smaller diesel
engine. We believe that the smaller engine would be attractive to some buyers, but not all, and
that those buyers would not be concerned by any possible lost utility. For that reason, we have
used a limited application rate for this technology. Note that, for HD pickups and vans, we have
considered this technology to be cost neutral.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-156 Costs for "Right-sized" HDD Tractor Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Right-sized
diesel engine
DMC
-$500
-$500
-$500
-$500
-$500
-$500
-$500
-$500
-$500
-$500
Right-sized
diesel engine
IC
$89
$89
$89
$89
$89
$89
$89
$89
$89
$89
Right-sized
diesel engine
TC
-$411
-$411
-$411
-$411
-$411
-$411
-$411
-$411
-$411
-$411
Right-sized
diesel engine
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Right-sized
diesel engine
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Right-sized
diesel engine
TCp
$0
$0
$0
-$41
-$41
-$41
-$82
-$82
-$82
-$123
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.15 Waste Heat Recovery
In the proposal, we estimated the cost of waste heat recovery based on the estimate from
Tetra Tech showing it at $12,000 (retail, 2013$). Using that $12,000 estimate and dividing by a
1.36 RPE (see Chapter 2.11.1.2 of this RIA) and converting to 2012$, we arrived at our
estimated DMC of $8,692 (DMC, 2012$, in 2018). For this final rule, we have updated our cost
of waste heat recovery based on new understanding of this technology. For this final rule, we
have chosen to start with one specific source considered by TetraTech in developing their cost
estimate. That source is the NESCCAF/ICCT/TIAX work which estimated the cost of the
technology at $15,100 having used an RPE of 2.0.206 Using the description of the technology by
NESCCAF, et al., TetraTech estimated the bill of materials (BOM) costs as shown below. Using
that BOM, along with updated understanding of more recent and future waste heat recovery
systems, EPA eliminated some of the items as unnecessary for the type of system and
effectiveness values that we envision (see Chapter 2.3 and 2.7 of this RIA). As shown in the
table below, EPA estimates the costs of waste heat recovery at $5463 (DMC, 2013$, in 2021)
and has considered this to be an applicable cost for MY2021.
Table 2-157 Direct Manufacturing Costs (DMC) for Waste Heat Recovery

MY2015 Cost


estimated by
EPA updates

TetraTech
(2013$)

(2009$)

Turbine generator & flywheel
$2160
$2309
Condenser
$550
$588
EGR boiler
$400
$428
Stack boiler
$1000
Not needed
Packaging, assembly, labor
$2000
$2138
Controls
$400
Not needed
Power electronics
$900
Not needed
Energy storage
$150
Not needed
Subtotal (direct mfg cost DMC)
$7560
$5463
RPE (2x subtotal)
$15120


-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
We consider this technology to be on the steep portion of the learning curve and have
generated a new learning curve in the final rule to accommodate this reworked cost estimate
(curve 14). We have applied a medium complexity ICM with short term markups through 2027.
The resultant technology costs, penetration rates and total cost applied to the package are
shown below.
Table 2-158 Costs for Waste Heat Recovery (WHR)
HDD Tractor Engines (2013$)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
WHR
DMC
$8,536
$6,829
$6,829
$5,463
$5,463
$4,370
$4,370
$3,496
$3,391
$3,290
WHR
IC
$1,807
$1,721
$1,721
$1,652
$1,652
$1,596
$1,596
$1,552
$1,547
$1,541
WHR
TC
$10,343
$8,550
$8,550
$7,115
$7,115
$5,967
$5,967
$5,048
$4,938
$4,831
WHR
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
WHR
Alt 3
0%
0%
0%
1%
1%
1%
5%
5%
5%
25%
WHR
TCp
$0
$0
$0
$71
$71
$60
$298
$252
$247
$1,208
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.16 Model-based Control
We have estimated the cost of model-based controls at $100 (DMC, 2013$, in 2021). We
consider this technology to be on the flat portion of the learning curve (curve 13) and have
applied a low complexity ICM with short term markups through 2022. The resultant technology
costs, penetration rates and total cost applied to the package are shown below.
Table 2-159 Costs for Model Based Controls
Light/Medium/Heavy HDD Vocational Engines (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Model-based control
DMC
$110
$106
$103
$100
$97
$94
$91
$89
$88
$86
Model-based control
IC
$16
$16
$15
$15
$15
$15
$15
$15
$15
$15
Model-based control
TC
$125
$122
$119
$115
$112
$110
$107
$105
$103
$101
Model-based control
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Model-based control
Alt 3
0%
0%
0%
25%
25%
25%
30%
30%
30%
40%
Model-based control
TCp
$0
$0
$0
$29
$28
$27
$32
$31
$31
$41
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.2.17 Engine Friction Reduction and Accommodating Low Friction
Lubes
We have based the costs for accommodating low friction lubes (LUB) on the costs used
in the light-duty 2017-2025 FRM but have scaled upward that cost by 50 percent to account for
the larger HD engines. Using that cost ($3 DMC, 2006$, in any year) and converting to 2012$
results in a cost of $5 (DMC, 2012$, in any year). We consider this technology to be beyond
learning (curve 1) and have applied low complexity markups with near term markups through
2018. The resultant costs for HD pickups and vans are shown in are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-160 Costs for Accommodating Low Friction Lubes
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Engine friction reduction - level 1
DMC
$5
$5
$5
$5
$5
$5
$5
Engine friction reduction - level 1
IC
$1
$1
$1
$1
$1
$1
$1
Engine friction reduction - level 1
TC
$6
$6
$6
$6
$6
$6
$6
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
We have based the costs for engine friction reduction level 1 (EFR1) on the costs used in
the light-duty 2017-2025 FRM. That cost is based on an original estimate of $11/cylinder
(DMC, 2006$, in any year). Using that cost for an 8 cylinder engine and converting to 2012$
results in a cost of $97 (DMC, 2012$, in any year). We consider this technology to be beyond
learning (curve 1) and have applied low complexity markups with near term markups through
2018. The resultant costs for HD pickups and vans are shown in are shown below.
Table 2-161 Costs for Engine Friction Reduction - Level 1
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Engine friction reduction - level 1
DMC
$97
$97
$97
$97
$97
$97
$97
Engine friction reduction - level 1
IC
$19
$19
$19
$19
$19
$19
$19
Engine friction reduction - level 1
TC
$116
$116
$116
$116
$116
$116
$116
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
For engine friction reduction level 2 (EFR2, which includes costs for accommodating low
friction lubes) we have used the same approach as used in the light-duty 2017-2025 rule in that
we have doubled the DMC associated with LUB and EFR1. As with those technologies, we
consider EFR2 to be beyond learning (curve 1) and have applied low complexity markups but
have applied near term markups through 2024. The resultant costs for gasoline HD pickups and
vans are shown below.
Table 2-162 Costs for Engine Friction Reduction - Level 2
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Engine friction reduction - level 2
DMC
$205
$205
$205
$205
$205
$205
$205
Engine friction reduction - level 2
IC
$50
$50
$50
$50
$39
$39
$39
Engine friction reduction - level 2
TC
$254
$254
$254
$254
$244
$244
$244
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
For diesel HD pickups and vans, we have used the above costs for EFR level 2 and added
to that costs associated with improvements to other parasitic loads on the engine. For that latter
portion of the cost, we have used the light HDD engine DMCs for improved water pump level 1,
improved oil pump level 1, improved fuel pump level 1, improved fuel injectors level 1 and
valvetrain friction reduction level 1, which together result in a cost of $193 (DMC, 2012$, in and
year). We consider this combined set of technologies to be beyond the effects of learning (curve
1) and have applied low complexity markups with near term markups through 2022. The
resultant costs for diesel HD pickups and vans are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-163 Costs for Engine Friction Reduction & Improvements to Other Parasitics
Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Engine friction reduction - diesel
DMC
$397
$397
$397
$397
$397
$397
$397
Engine friction reduction - diesel
IC
$96
$96
$87
$87
$77
$77
$77
Engine friction reduction - diesel
TC
$494
$494
$484
$484
$474
$474
$474
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.2.18 Cylinder Deactivation
For cylinder deactivation on HD pickups and vans, we have based the costs on values
presented in the light-duty 2017-2025 FRM with updates to 2012$ to arrive at a cost of $169
(DMC, 2012$, in 2015). We consider this technology to be on the flat portion of the learning
curve (curve 8) and have applied medium complexity markups with near term markups through
2018. The resultant costs are presented below.
Table 2-164 Costs for Cylinder Deactivation
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Cylinder deactivation
DMC
$148
$145
$142
$139
$137
$135
$134
Cylinder deactivation
IC
$48
$48
$48
$48
$48
$48
$48
Cylinder deactivation
TC
$196
$193
$190
$187
$185
$183
$182
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.2.19 Stoichiometric Gasoline Direct Injection (SGDI)
For gasoline direct injection on HD pickups and vans, we have based the costs on values
presented in the light-duty 2017-2025 FRM with updates to 2012$ to arrive at a cost of $417
(DMC, 2012$, in 2012). We consider this technology to be on the flat portion of the learning
curve (curve 7) and have applied medium complexity markups with near term markups through
2018. The resultant costs are presented below.
Table 2-165 Costs for Direct Injection
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Gasoline direct injection
DMC
$333
$327
$320
$314
$307
$304
$301
Gasoline direct injection
IC
$118
$118
$118
$117
$117
$117
$117
Gasoline direct injection
TC
$451
$445
$438
$431
$425
$422
$418
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost.
2.11.2.20 Turbocharging & Downsizing
For turbocharging and downsizing (TDS) on HD pickups and vans, we have based the
costs on values presented in the light-duty 2017-2025 FRM with updates to 2012$. For the twin
turbo configuration expected on a V6 engine (downsized from a V8), we estimate the cost at
$735 (DMC, 2012$, in 2012). We consider this technology to be on the flat portion of the
learning curve (curve 7) and have applied medium complexity markups with near term markups
through 2018. For downsizing from an overhead valve (OHV) V8 to an overhead cam (OHC)

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
V6 valvetrain, we have estimated the cost at $340 (DMC, 2012$, in 2017). We consider this
technology to be on the flat portion of the learning curve (curve 6) and have applied medium
complexity markups with near term markups through 2018. For downsizing from an OHC V8 to
an OHC V6, we have estimated the cost at -$295 (DMC, 2012$, in 2012). We consider this
technology to be on the flat portion of the learning curve to arrive at a cost of $417 (DMC,
2012$, in 2012). We consider this technology to be on the flat portion of the learning curve
(curve 7) and have applied medium complexity markups with near term markups through 2024.
The resultant costs for the turbocharging system and for downsizing from an OHV V8 to an
OHC V6 are shown below, and downsizing from an OHC V8 to an OHC V6 are also shown
below.
Table 2-166 Costs for Adding Twin Turbos
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Adding twin turbos
DMC
$588
$576
$565
$553
$542
$537
$531
Adding twin turbos
IC
$208
$208
$208
$207
$207
$207
$207
Adding twin turbos
TC
$796
$784
$772
$761
$749
$744
$738
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-167 Costs for Downsizing from an OHV V8 to an OHC V6
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Downsizing from OHV
V8 to OHC V6
DMC
$301
$292
$286
$280
$275
$269
$264
Downsizing from OHV
V8 to OHC V6
IC
$97
$97
$97
$97
$96
$96
$96
Downsizing from OHV
V8 to OHC V6
TC
$398
$389
$383
$377
$371
$365
$360
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-168 Costs for Downsizing from an OHC V8 to an OHC V6
Gasoline HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Downsizing from OHC
V8 to OHC V6
DMC
-$236
-$232
-$227
-$223
-$218
-$216
-$214
Downsizing from OHC
V8 to OHC V6
IC
$112
$112
$111
$111
$83
$83
$83
Downsizing from OHC
V8 to OHC V6
TC
-$125
-$120
-$116
-$111
-$135
-$133
-$131
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.3 Transmissions
2.11.3.1 Adding Additional Gears (Vocational)
We have estimated the cost of adding 2 additional gears for vocational vehicles
(light/medium HD, heavy HD urban/multipurpose) based on the light-duty cost for an 8 speed

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
automatic transmission relative to a 6 speed automatic of $78 (DMC, 2010$, in 2012).Q We
have scaled that value by typical torque values of 2000 foot-pounds for vocational and 332 for a
light-duty truck. With updates to 2013$, this DMC for vocational vehicles becomes $495
(DMC, 2013$, in 2012). We consider this technology to be on the flat portion of the learning
curve (curve 7) and have applied a medium complexity ICM with short term markups through
2018. The resultant technology costs, penetration rates and total cost applied to the package are
shown below.
Table 2-169 Costs for Adding 2 Gears to an Automatic Transmission
Vocational Light/Medium HD Urban/Multipurpose/Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Adding additional gears
DMC
$421
$413
$404
$396
$388
$380
$373
$365
$362
$358
Adding additional gears
IC
$146
$109
$109
$108
$108
$108
$107
$107
$107
$107
Adding additional gears
TC
$567
$521
$513
$504
$496
$488
$480
$473
$469
$465
Adding additional gears
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Adding additional gears
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
20%
Adding additional gears
TCp
$0
$0
$0
$50
$50
$49
$96
$95
$94
$93
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-170 Costs for Adding 2 Gears to an Automatic Transmission
Vocational Heavy HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Adding additional gears
DMC
$421
$413
$404
$396
$388
$380
$373
$365
$362
$358
Adding additional gears
IC
$146
$109
$109
$108
$108
$108
$107
$107
$107
$107
Adding additional gears
TC
$567
$521
$513
$504
$496
$488
$480
$473
$469
$465
Adding additional gears
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Adding additional gears
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
10%
Adding additional gears
TCp
$0
$0
$0
$25
$25
$24
$48
$47
$47
$47
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.3.2 Automated/Automated Manual Transmissions (AMT)
We have estimated the cost of an AMT transmission, relative to a manual transmission,
based on an estimate by Tetra Tech of $5,100 (retail, 2013$). Using that estimate, we divided by
an RPE of 1.36 to arrive at an estimated cost of $3750 (DMC, 2013$, in 2018). We consider this
technology to be on the flat portion of the learning curve (curve 12) and have applied a medium
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Q This cost was updated by FEV in early 2013. We are using the updated cost here, not the value used in the light-
duty 2017-2025 final rule.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-171 Costs for an Automated Transmission
Vocational Heavy HD & Heavy HD Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Manual to AMT
DMC
$3,750
$3,638
$3,528
$3,423
$3,354
$3,287
$3,221
$3,157
$3,094
$3,032
Manual to AMT
IC
$1,134
$1,128
$1,123
$1,117
$1,114
$830
$828
$825
$823
$821
Manual to AMT
TC
$4,884
$4,766
$4,651
$4,540
$4,468
$4,117
$4,049
$3,982
$3,917
$3,853
Manual to AMT
Alt
la
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
Manual to AMT
Alt 3
80%
80%
80%
85%
85%
85%
100%
100%
100%
100%
Manual to AMT
TCp
$0
$0
$0
$227
$223
$206
$810
$796
$783
$771
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-172 Costs for an Automated Transmission
Vocational Heavy HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Manual to AMT
DMC
$3,750
$3,638
$3,528
$3,423
$3,354
$3,287
$3,221
$3,157
$3,094
$3,032
Manual to AMT
IC
$1,134
$1,128
$1,123
$1,117
$1,114
$830
$828
$825
$823
$821
Manual to AMT
TC
$4,884
$4,766
$4,651
$4,540
$4,468
$4,117
$4,049
$3,982
$3,917
$3,853
Manual to AMT
Alt
la
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
Manual to AMT
Alt 3
5%
5%
5%
35%
35%
35%
55%
55%
55%
85%
Manual to AMT
TCp
$0
$0
$0
$1,362
$1,340
$1,235
$2,024
$1,991
$1,958
$3,082
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-173 Costs for an AMT Transmission
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Manual to AMT
DMC
$3,750
$3,638
$3,528
$3,423
$3,354
$3,287
$3,221
$3,157
$3,094
$3,032
Manual to AMT
IC
$1,134
$1,128
$1,123
$1,117
$1,114
$830
$828
$825
$823
$821
Manual to AMT
TC
$4,884
$4,766
$4,651
$4,540
$4,468
$4,117
$4,049
$3,982
$3,917
$3,853
Manual to AMT
Alt
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
la
Manual to AMT
Alt 3
0%
0%
0%
40%
40%
40%
50%
50%
50%
50%
Manual to AMT
TCp
$0
$0
$0
$1,816
$1,787
$1,647
$2,024
$1,991
$1,958
$1,926
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.3.3 Automatic Transmission Powershift
We have estimated the cost of a powershift automatic transmission, relative to a manual
transmission, based on an estimate by Tetra Tech of $15000 (retail, 2013$). Using that estimate,
we divided by an RPE of 1.36 to arrive at an estimated cost of $11883 (DMC, 2013$, in 2018).
We consider this technology to be on the flat portion of the learning curve (curve 12) and have
applied a medium complexity ICM with short term markups through 2022. The resultant
technology costs, penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-174 Costs for a Powershift Automatic Transmission
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Manual to AT
powershift
DMC
$11,883
$11,527
$11,181
$10,846
$10,629
$10,416
$10,208
$10,004
$9,803
$9,607
Manual to AT
powershift
IC
$3,593
$3,575
$3,557
$3,540
$3,529
$2,630
$2,623
$2,616
$2,608
$2,602
Manual to AT
powershift
TC
$15,476
$15,101
$14,738
$14,386
$14,158
$13,046
$12,830
$12,619
$12,412
$12,209
Manual to AT
powershift
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Manual to AT
powershift
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Manual to AT
powershift
TCp
$0
$0
$0
$1,439
$1,416
$1,305
$2,566
$2,524
$2,482
$3,663
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.3.4 Dual-clutch Transmissions (DCT)
For tractors, we have based our estimated cost of a DCT relative to a manual transmission
on a Tetra Tech estimate of $17,500 (retail, 2013$). Using that estimate, we divided by an RPE
of 1.36 to arrive at an estimated cost of $12,868 (DMC, 2013$, in 2018). We consider this
technology to be on the flat portion of the learning curve (curve 12) and have applied a medium
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-175 Costs for a Dual Clutch Transmission (DCT)
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Manual to DCT
DMC
$12,868
$12,482
$12,107
$11,744
$11,509
$11,279
$11,053
$10,832
$10,616
$10,403
Manual to DCT
IC
$3,890
$3,871
$3,852
$3,833
$3,821
$2,848
$2,840
$2,832
$2,825
$2,817
Manual to DCT
TC
$16,758
$16,352
$15,959
$15,577
$15,331
$14,127
$13,893
$13,664
$13,440
$13,220
Manual to DCT
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Manual to DCT
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
10%
Manual to DCT
TCp
$0
$0
$0
$779
$767
$706
$1,389
$1,366
$1,344
$1,322
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.3.5 High Efficiency Gearbox (HEG)
For this technology, we have relied on our light-duty technology referred to as high
efficiency gearbox (HEG). This technology was estimated at $200(DMC, in 2010$, in 2015).
For this analysis, we have used that estimate but have scaled upward the cost of HEG by 25
percent to account for differences between light-duty and HD. Converting to 2013$ results in
costs for this technology of $267 (DMC, 2013$, in 2021). We consider this technology to be on
the flat portion of the learning curve (curve 13) and have applied a low complexity ICM with

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
short term markups through 2022. The resultant technology costs, penetration rates and total cost
applied to the package are shown below.
Table 2-176 Costs of Improved Transmissions
Vocational Light/Medium/Heavy HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
HEG
DMC
$293
$284
$276
$267
$259
$252
$244
$239
$234
$230
HEG
IC
$48
$48
$48
$48
$48
$37
$37
$37
$37
$37
HEG
TC
$341
$332
$323
$315
$307
$289
$281
$276
$272
$267
HEG
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
HEG
Alt 3
0%
0%
0%
50%
50%
50%
60%
60%
60%
62%
HEG
TCp
$0
$0
$0
$158
$153
$144
$169
$166
$163
$165
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-177 Costs of Improved Transmissions
Vocational Light/Medium/Heavy HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
HEG
DMC
$293
$284
$276
$267
$259
$252
$244
$239
$234
$230
HEG
IC
$48
$48
$48
$48
$48
$37
$37
$37
$37
$37
HEG
TC
$341
$332
$323
$315
$307
$289
$281
$276
$272
$267
HEG
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
HEG
Alt 3
0%
0%
0%
50%
50%
50%
60%
60%
60%
70%
HEG
TCp
$0
$0
$0
$158
$153
$144
$169
$166
$163
$187
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-178 Costs for High Efficiency Gearbox (HEG) on Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
HEG
DMC
$293
$284
$276
$267
$259
$252
$244
$239
$234
$230
HEG
IC
$48
$48
$48
$48
$48
$37
$37
$37
$37
$37
HEG
TC
$341
$332
$323
$315
$307
$289
$281
$276
$272
$267
HEG
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
HEG
Alt 3
0%
0%
0%
20%
20%
20%
40%
40%
40%
70%
HEG
TCp
$0
$0
$0
$63
$61
$58
$113
$111
$109
$187
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.3.6 Early Torque Converter Lockup (TORQ) - Vocational Vehicles
For this technology, we have relied on our light-duty technology of the same. This
technology was estimated at $25 (DMC, in 2010$, in 2015). For this analysis, we have used that
estimate converted to 2013$ resulting in a cost for this technology of $26 (DMC, 2013$, in
2021). We consider this technology to be on the flat portion of the learning curve (curve 8) and
have applied a low complexity ICM with short term markups through 2018. The resultant
technology costs, penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-179 Costs of Early Torque Converter Lockup (TORQ)
Vocational Light/Medium HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TORQ
DMC
$28
$28
$27
$26
$25
$24
$24
$23
$23
$22
TORQ
IC
$5
$5
$5
$5
$5
$4
$4
$4
$4
$4
TORQ
TC
$33
$32
$31
$31
$30
$28
$27
$27
$26
$26
TORQ
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TORQ
Alt 3
0%
0%
0%
30%
30%
30%
40%
40%
40%
50%
TORQ
TCp
$0
$0
$0
$9
$9
$8
$11
$11
$11
$13
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-180 Costs of Early Torque Converter Lockup (TORQ)
Vocational Heavy HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TORQ
DMC
$28
$28
$27
$26
$25
$24
$24
$23
$23
$22
TORQ
IC
$5
$5
$5
$5
$5
$4
$4
$4
$4
$4
TORQ
TC
$33
$32
$31
$31
$30
$28
$27
$27
$26
$26
TORQ
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TORQ
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
TORQ
TCp
$0
$0
$0
$3
$3
$3
$5
$5
$5
$8
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.3.7 Driveline Integration - Vocational Vehicles
We have estimated the cost of driveline integration on comments regarding the cost of
neutral idle.207 While the comment was not speaking to driveline integration, we believe that the
rationale of the comment and the cost estimate made by the commenter are applicable to the
driveline integration technology in terms of sensors and calibration required. We have divided
this cost by 1.36 to arrive at a direct manufacturing cost of $74 (DMC, 2013$, in 2021). We
consider this technology to be on the flat portion of the learning curve (curve 13) and have
applied a low complexity ICM with short term markups through 2022. The resultant technology
costs, penetration rates and total cost applied to the package are shown below.
Table 2-181 Costs of Driveline Integration
Vocational Light/Medium/Heavy HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved trans
DMC
$81
$78
$76
$74
$71
$69
$67
$66
$64
$63
Improved trans
IC
$13
$13
$13
$13
$13
$10
$10
$10
$10
$10
Improved trans
TC
$94
$91
$89
$87
$84
$79
$77
$76
$75
$73
Improved trans
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved trans
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
24%
Improved trans
TCp
$0
$0
$0
$9
$8
$8
$15
$15
$15
$18
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-182 Costs of Driveline Integration
Vocational Light/Medium/Heavy HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved trans
DMC
$81
$78
$76
$74
$71
$69
$67
$66
$64
$63
Improved trans
IC
$13
$13
$13
$13
$13
$10
$10
$10
$10
$10
Improved trans
TC
$94
$91
$89
$87
$84
$79
$77
$76
$75
$73
Improved trans
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved trans
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Improved trans
TCp
$0
$0
$0
$9
$8
$8
$15
$15
$15
$22
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.3.8 8 Speed Transmission Relative to a 6 Speed, HD Pickups & Vans
We have based the cost of this technology on several values used in the light-duty 2017-
2025 final rule. In that rule, we presented costs for 6 to 8 speed automatic transmission, high
efficiency gearbox (HEG) and aggressive shift logic (ASL1) as separate technologies. Here we
are treating these technologies as separate for costing (since some metrics differ for each) but
considering them as being applied together as a complete group. As such, the cost for moving to
an 8 speed transmission from the base 6 would always be the summation within any given year
of the total costs shown in the tables that follow. For adding 2 gears, we have estimated the cost
at $121 (DMC, 2012$, in 2012). We consider that technology to be on the flat portion of the
learning curve (curve 7) and have applied medium complexity markups with near term markups
through 2018. For HEG, we have estimated the cost at $263 (DMC, 2012$, in 2017). We
consider this technology to be on the flat portion of the learning curve (curve 6) and have applied
low complexity markups with near term markups through 2024. For shift logic, we have
estimated the cost at $28 (DMC, 2012$, in 2015). We consider this technology to be on the flat
portion of the learning curve (curve 8) and have applied low complexity markups with near term
markups through 2018. The resultant costs for these technologies are shown below.
Table 2-183 Costs to Add 2 Transmission Gears
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Move from 6 to 8 gears
DMC
$97
$95
$93
$91
$89
$88
$88
Move from 6 to 8 gears
IC
$34
$34
$34
$34
$34
$34
$34
Move from 6 to 8 gears
TC
$131
$129
$127
$125
$123
$123
$122
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-184 Costs for High Efficiency Gearbox (HEG)
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
High efficiency gearbox
DMC
$232
$225
$221
$217
$212
$208
$204
High efficiency gearbox
IC
$63
$63
$63
$63
$50
$50
$50
High efficiency gearbox
TC
$296
$288
$284
$279
$262
$258
$254
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-185 Costs for Aggressive Shift Logic Level 1
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Aggressive shift logic 1
DMC
$25
$24
$24
$23
$23
$22
$22
Aggressive shift logic 1
IC
$5
$5
$5
$5
$5
$5
$5
Aggressive shift logic 1
TC
$30
$30
$29
$29
$28
$28
$28
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-186 Complete Cost of Moving from the Base 6 Speed to 8 Speed Transmission
2 Gears+HEG+ASLl
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Move from 6speed to
8speed Transmission
TC
$457
$447
$440
$433
$414
$409
$403
Notes: TC=total cost.
2.11.4 Air Conditioning
2.11.4.1 Direct AC Controls - Vocational (all)
We have estimated the cost of this technology based on an estimate from TetraTech of
$30 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a cost of $22
(DMC, 2013$, in 2014). We consider this technology to be on the flat portion of the learning
curve (curve 2) and have applied a low complexity ICM with short term markups through 2022.
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-187 Costs for Direct Air Conditioning Controls
All Vocational HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
A/C direct
DMC
$20
$19
$19
$18
$18
$18
$17
$17
$17
$17
A/C direct
IC
$4
$4
$4
$4
$4
$3
$3
$3
$3
$3
A/C direct
TC
$23
$23
$23
$22
$22
$21
$20
$20
$20
$20
A/C direct
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
A/C direct
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
100%
A/C direct
TCp
$0
$0
$0
$22
$22
$21
$20
$20
$20
$20
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.4.2 Indirect AC Controls - Tractors (all)
We have estimated the cost of this technology based on an estimate from TetraTech of
$218 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a cost of $160
(DMC, 2013$, in 2018). We consider this technology to be on the flat portion of the learning
curve (curve 12) and have applied a low complexity ICM with short term markups through 2022.
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-188 Costs for Indirect AC Controls
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
A/C indirect
DMC
$160
$155
$150
$146
$143
$140
$137
$135
$132
$129
A/C indirect
IC
$29
$28
$28
$28
$28
$22
$22
$22
$22
$22
A/C indirect
TC
$188
$184
$179
$174
$171
$162
$160
$157
$154
$152
A/C indirect
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
A/C indirect
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
A/C indirect
TCp
$0
$0
$0
$17
$17
$16
$32
$31
$31
$45
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.5 Axles
2.11.5.1 6x2 Axle
We have estimated the cost of this technology based on an estimate from TetraTech of
$250 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a cost of $184
(DMC, 2013$, in 2018). We consider this technology to be on the flat portion of the learning
curve (curve 12) and have applied a low complexity ICM with short term markups through 2022.
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-189 Costs for 6x2 Axles
Class 8 Day Cab and Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle 6x2
DMC
$184
$178
$173
$168
$164
$161
$158
$155
$152
$149
Axle 6x2
IC
$33
$33
$33
$33
$33
$26
$26
$26
$26
$26
Axle 6x2
TC
$217
$211
$206
$200
$197
$187
$183
$180
$177
$174
Axle 6x2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle 6x2
Alt 3
0%
0%
0%
15%
15%
15%
25%
25%
25%
30%
Axle 6x2
TCp
$0
$0
$0
$30
$30
$28
$46
$45
$44
$52
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.5.2 Axle Disconnect
We have estimated the cost of this technology based on an estimate from TetraTech of
$140 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a cost of $103
(DMC, 2013$, in all years). We consider this technology to be on the flat portion of the learning
curve with no additional learning to occur (curve 1) and have applied a low complexity ICM
with short term markups through 2022. The resultant technology costs, penetration rates and
total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-190 Costs for Axle Disconnect
Vocational Heavy HD Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle disconnect
DMC
$103
$103
$103
$103
$103
$103
$103
$103
$103
$103
Axle disconnect
IC
$18
$18
$18
$18
$18
$14
$14
$14
$14
$14
Axle disconnect
TC
$121
$121
$121
$121
$121
$117
$117
$117
$117
$117
Axle disconnect
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle disconnect
Alt 3
0%
0%
0%
5%
5%
5%
15%
15%
15%
25%
Axle disconnect
TCp
$0
$0
$0
$6
$6
$6
$18
$18
$18
$29
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-191 Costs for Axle Disconnect
Vocational Heavy HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle disconnect
DMC
$103
$103
$103
$103
$103
$103
$103
$103
$103
$103
Axle disconnect
IC
$18
$18
$18
$18
$18
$14
$14
$14
$14
$14
Axle disconnect
TC
$121
$121
$121
$121
$121
$117
$117
$117
$117
$117
Axle disconnect
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle disconnect
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Axle disconnect
TCp
$0
$0
$0
$12
$12
$12
$23
$23
$23
$35
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.5.3 Axle Downspeed
We have estimated the cost of this technology based on engineering judgment at $50
(DMC, 2013$, in 2018). This DMC is expected to cover development and some testing and
integration work since there is no real hardware required for this technology. We consider this
technology to be on the flat portion of the learning curve (curve 12) and have applied a low
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-192 Costs for Axle Downspeeding
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle downspeed
DMC
$50
$49
$47
$46
$45
$44
$43
$42
$41
$40
Axle downspeed
IC
$9
$9
$9
$9
$9
$7
$7
$7
$7
$7
Axle downspeed
TC
$59
$57
$56
$54
$54
$51
$50
$49
$48
$47
Axle downspeed
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle downspeed
Alt 3
0%
0%
0%
20%
20%
20%
40%
40%
40%
60%
Axle downspeed
TCp
$0
$0
$0
$11
$11
$10
$20
$20
$19
$28
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.5.4 High Efficiency Axle (Axle HE)
We have estimated the cost of this technology based on an estimate from TetraTech of
$250 (retail, 2013$), an estimate applicable to tractors having 3 axles. Using that estimate we
divided by a 1.36 RPE to arrive at a cost of $184 (DMC, 2013$, in 2018). We consider this
estimate to be applicable also to vocational HH vehicles since these generally have 3 axles. For
vocational light/medium HD vehicles, which generally have 2 axles, we have estimated the
DMC at 2/3 the vocational heavy HD/tractor cost, or $123 (DMC, 2013$, in 2018). We consider
this technology to be on the flat portion of the learning curve (curve 12) and have applied a low
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-193 Costs for High Efficiency Axles
Vocational Light/Medium HD Urban/Multipurpose/Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle low friction lubes
DMC
$123
$119
$115
$112
$110
$107
$105
$103
$101
$99
Axle low friction lubes
IC
$22
$22
$22
$22
$22
$17
$17
$17
$17
$17
Axle low friction lubes
TC
$144
$141
$137
$134
$131
$124
$122
$120
$118
$116
Axle low friction lubes
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle low friction lubes
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Axle low friction lubes
TCp
$0
$0
$0
$13
$13
$12
$24
$24
$24
$35
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-194 Costs for High Efficiency Axles
Vocational Heavy HD Urban/Multipurpose/Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle low friction lubes
DMC
$184
$178
$173
$168
$164
$161
$158
$155
$152
$149
Axle low friction lubes
IC
$33
$33
$33
$33
$33
$26
$26
$26
$26
$26
Axle low friction lubes
TC
$217
$211
$206
$200
$197
$187
$183
$180
$177
$174
Axle low friction lubes
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle low friction lubes
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Axle low friction lubes
TCp
$0
$0
$0
$20
$20
$19
$37
$36
$35
$52
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-195 Costs for High Efficiency Axles
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Axle low friction lubes
DMC
$184
$178
$173
$168
$164
$161
$158
$155
$152
$149
Axle low friction lubes
IC
$33
$33
$33
$33
$33
$26
$26
$26
$26
$26
Axle low friction lubes
TC
$217
$211
$206
$200
$197
$187
$183
$180
$177
$174
Axle low friction lubes
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Axle low friction lubes
Alt 3
0%
0%
0%
30%
30%
30%
65%
65%
65%
80%
Axle low friction lubes
TCp
$0
$0
$0
$60
$59
$56
$119
$117
$115
$139
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.6 Idle Reduction
2.11.6.1 Auxiliary Power Units (APU)
We have estimated the cost of the APU technology at $8000 retail (2013$). We divided
that by 1.36 to arrive at a cost of $5882 (DMC, 2013$, in 2014). We consider this technology to
be on the flat portion of the learning curve (curve 2) and have applied a low complexity ICM
with short term markups through 2022. The resultant technology costs, penetration rates and
total cost applied to the package are shown below.
Table 2-196 Costs for Auxiliary Power Units (APU)
On Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
APU
DMC
$5,208
$5,103
$5,001
$4,901
$4,803
$4,707
$4,613
$4,521
$4,476
$4,431
APU
IC
$1,041
$1,039
$1,038
$1,037
$1,035
$817
$816
$816
$815
$815
APU
TC
$6,248
$6,143
$6,039
$5,938
$5,839
$5,524
$5,429
$5,336
$5,291
$5,246
APU
Alt
la
9%
9%
9%
9%
9%
9%
0%
0%
0%
0%
APU
Alt 3
9%
9%
9%
30%
30%
30%
0%
0%
0%
0%
APU
TCp
$0
$0
$0
$1,247
$1,226
$1,160
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.6.2 Auxiliary Power Units, Battery Powered (APUB)
We have estimated the cost of the battery powered APU technology at $6400 retail
(2013$). We divided that by 1.36 to arrive at a cost of $5070 (DMC, 2013$, in 2014). We
consider this technology to be on the flat portion of the learning curve (curve 2) and have applied
a low complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-197 Costs for Battery Powered Auxiliary Power Units (APU B) on Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
APU B
DMC
$4,489
$4,399
$4,311
$4,225
$4,140
$4,057
$3,976
$3,897
$3,858
$3,819
APU B
IC
$897
$896
$895
$894
$893
$704
$703
$703
$703
$702
APU B
TC
$5,386
$5,295
$5,206
$5,118
$5,033
$4,761
$4,680
$4,600
$4,560
$4,522
APUB
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
APU B
Alt 3
0%
0%
0%
10%
10%
10%
10%
10%
10%
15%
APU B
TCp
$0
$0
$0
$512
$503
$476
$468
$460
$456
$678
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.6.3 Auxiliary Power Units with Diesel Particulate Filters (APUwDPF)
We have estimated the cost of the DPF equipped APU technology at $10,000 retail
(2013$). See Preamble Section III.C for an explanation of the estimate for the cost of the APU.
We divided that by 1.36 to arrive at a cost of $7922 (DMC, 2013$, in 2014). We consider this
technology to be on the flat portion of the learning curve (curve 2) and have applied a low

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.
Table 2-198 Costs for Auxiliary Power Units with Diesel Particulate Filters (APUwDPF) on Sleeper Cab
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
APUwDPF
DMC
$7,013
$6,873
$6,736
$6,601
$6,469
$6,340
$6,213
$6,089
$6,028
$5,967
APUwDPF
IC
$1,402
$1,400
$1,398
$1,396
$1,395
$1,100
$1,099
$1,098
$1,098
$1,098
APUwDPF
TC
$8,415
$8,273
$8,134
$7,997
$7,864
$7,439
$7,312
$7,187
$7,126
$7,065
APUwDPF
Alt
la
0%
0%
0%
0%
0%
0%
9%
9%
9%
9%
APUwDPF
Alt 3
0%
0%
0%
0%
0%
0%
40%
40%
40%
40%
APUwDPF
TCp
$0
$0
$0
$0
$0
$0
$2,267
$2,228
$2,209
$2,190
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.6.4 Fuel Operated Heater (FOH)
We have estimated the cost of the FOH technology at $1200 retail (2013$). We divided
that by 1.36 to arrive at a cost of $882 (DMC, 2013$, in 2014). We consider this technology to
be on the flat portion of the learning curve (curve 2) and have applied a low complexity ICM
with short term markups through 2022. The resultant technology costs, penetration rates and
total cost applied to the package are shown below.
Table 2-199 Costs for Fuel Operated Heaters (FOH) on Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
FOH
DMC
$781
$766
$750
$735
$720
$706
$692
$678
$671
$665
FOH
IC
$156
$156
$156
$156
$155
$122
$122
$122
$122
$122
FOH
TC
$937
$921
$906
$891
$876
$829
$814
$800
$794
$787
FOH
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
FOH
Alt 3
0%
0%
0%
0%
10%
10%
10%
10%
10%
15%
FOH
TCp
$0
$0
$0
$0
$88
$83
$81
$80
$79
$118
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.6.5 Neutral Idle
We have estimated the cost of neutral idle on comments received.208 A commenter stated
that a cost of $100 would be more appropriate than the estimate used in the proposal. We have
considered the $100 estimate to be in 2013$ and applicable in all years meaning that we consider
this technology to be on the flat portion of the learning curve with no additional learning to occur
(curve 1) and have applied a low complexity ICM with short term markups through 2022. The
resultant technology costs, penetration rates and total cost applied to the package are below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-200 Costs for Neutral Idle Technology
Vocational Light/Medium/Heavy HD Urban/Multipurpose Vehicles
(2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Neutral idle
DMC
$100
$100
$100
$100
$100
$100
$100
$100
$100
$100
Neutral idle
IC
$18
$18
$18
$18
$18
$14
$14
$14
$14
$14
Neutral idle
TC
$118
$118
$118
$118
$118
$114
$114
$114
$114
$114
Neutral idle
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Neutral idle
Alt 3
0%
0%
0%
50%
50%
50%
70%
70%
70%
60%
Neutral idle
TCp
$0
$0
$0
$59
$59
$57
$80
$80
$80
$68
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.6.6 Stop-start with Enhancements (Stop-startenhanced)
We have estimated the cost of this technology based on several cost estimates. First, an
estimate from TetraTech of $700 (retail, 2013$) for gasoline HD pickups and vans and $1500
(retail, 2013$) for diesel HD pickups and vans. Using these values, we divided by a 1.36 RPE to
arrive at $515 (DMC, 2013$, in 2021) and $1103 (DMC, 2013$, in 2021) which were considered
appropriate for vocational MH and HH vehicles, respectively. To these estimates, we have
added the costs for improved accessories used for HD pickups and vans of $126 (DMC, 2013$,
in 2015) which is based on values from the 2017-2025 light-duty FRM. However, to account for
the heavier vocational vehicles relative to the HD pickup and vans, we have scaled upward the
improved accessory value by 50 percent to arrive at a cost of $189 (DMC, 2013$, in 2015). We
have then added these values to arrive at costs of $704 (DMC, 2013$, in 2021) and $1292
(DMC, 2013$, in 2021) and have applied the lower cost to vocational medium HD vehicles and
the higher cost to vocational heavy HD vehicles. For vocational light HD, we have used the
stop-start cost for the 2017-2025 rule for LD pickups ($377 DMC, 2012$, in 2015) but have
scaled upward that value by 25 percent to account for the weight difference between the LD and
vocational light HD vehicles. Doing this results in a cost of $479 (DMC, 2013$, in 2021).
Adding to that the $189 value for improved accessories mentioned earlier gives the resultant
vocational light HD cost of $669 (DMC, 2013$, in 2021). We consider all of these technologies
to be on the flat portion of the learning curve (curve 13) and have applied a medium complexity
ICM with short term markups through 2022. The resultant technology costs, penetration rates
and total cost applied to the package are shown below.
Table 2-201 Costs for Enhanced Stop-start with Enhancements
Vocational Light HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Stop-start enhanced
DMC
$733
$711
$689
$669
$648
$629
$610
$598
$586
$574
Stop-start enhanced
IC
$205
$204
$203
$202
$201
$149
$149
$148
$148
$148
Stop-start enhanced
TC
$938
$915
$892
$871
$850
$779
$759
$746
$734
$722
Stop-start enhanced
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Stop-start enhanced
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Stop-start enhanced
TCp
$0
$0
$0
$87
$85
$78
$152
$149
$147
$217
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-202 Costs for Enhanced Stop-start Vocational Medium HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Stop-start enhanced
DMC
$771
$748
$726
$704
$683
$662
$642
$630
$617
$605
Stop-start enhanced
IC
$216
$215
$214
$213
$212
$157
$157
$156
$156
$155
Stop-start enhanced
TC
$987
$963
$939
$917
$894
$820
$799
$786
$773
$760
Stop-start enhanced
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Stop-start enhanced
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Stop-startenhanced
TCp
$0
$0
$0
$92
$89
$82
$160
$157
$155
$228
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-203 Costs for Enhanced Stop-start Vocational Heavy HD Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Stop-start enhanced
DMC
$1,416
$1,373
$1,332
$1,292
$1,253
$1,216
$1,179
$1,156
$1,133
$1,110
Stop-start enhanced
IC
$397
$395
$393
$391
$389
$289
$288
$287
$286
$285
Stop-start enhanced
TC
$1,813
$1,768
$1,725
$1,683
$1,642
$1,505
$1,467
$1,442
$1,419
$1,395
Stop-start enhanced
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Stop-start enhanced
Alt 3
0%
0%
0%
0%
0%
0%
10%
10%
10%
20%
Stop-start enhanced
TCp
$0
$0
$0
$0
$0
$0
$147
$144
$142
$279
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
For HD pickups and vans, we have based our costs for stop-start systems on the values
used in the light-duty 2017-2025 final rule, but have scaled upward those costs by 25 percent to
account for the larger and harder starting HD engines. Using this approach and converting to
2012$ results in a cost of $471 (DMC, 2012$, in 2015). We consider this technology to be on
the steep portion of the learning curve (curve 9, note the different year of cost-applicability
relative to the vocational cost discussed above) and have applied medium complexity markups
with near term markups through 2018. The resultant costs for HD pickups and vans are shown
below.
Table 2-204 Costs of Stop-start
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Stop-start
DMC
$404
$392
$380
$369
$358
$351
$344
Stop-start
IC
$134
$134
$134
$133
$133
$133
$132
Stop-start
TC
$539
$526
$514
$502
$491
$483
$476
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.6.7 Automatic Engine Shutdown System (AESS)
We have estimated the cost of an AESS at $50 retail (2013$). This system should be low
cost since the engine control software already features the necessary code. The cost here is
simply meant to cover the costs of setting the software correctly to take advantage of the already
existing feature. We have divided the $50 by 1.36 to arrive at a cost of $40 (DMC, 2013$, in
2014). We have placed this technology on the steep portion of the learning curve today but flat
by the 2019 timeframe (curve 4) and have applied a low complexity ICM with short term

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
markups through 2022. The resultant technology costs, penetration rates and total cost applied to
the package are shown below.
Table 2-205 Costs for Automatic Engine Shutdown System on Vocational Light/Medium/Heavy HD
Urban/Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
AESS
DMC
$25
$25
$24
$23
$22
$22
$21
$20
$20
$20
AESS
IC
$7
$7
$7
$7
$7
$5
$5
$5
$5
$5
AESS
TC
$32
$31
$31
$30
$29
$27
$27
$26
$26
$25
AESS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
AESS
Alt 3
0%
0%
0%
30%
30%
30%
60%
60%
60%
70%
AESS
TCp
$0
$0
$0
$9
$9
$8
$16
$16
$15
$18
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-206 Costs for Automatic Engine Shutdown System on Vocational Light/Medium/Heavy HD Regional
Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
AESS
DMC
$25
$25
$24
$23
$22
$22
$21
$20
$20
$20
AESS
IC
$7
$7
$7
$7
$7
$5
$5
$5
$5
$5
AESS
TC
$32
$31
$31
$30
$29
$27
$27
$26
$26
$25
AESS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
AESS
Alt 3
0%
0%
0%
40%
40%
40%
80%
80%
80%
90%
AESS
TCp
$0
$0
$0
$12
$12
$11
$21
$21
$20
$23
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-207 Costs for Automatic Engine Shutdown System on Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
AESS
DMC
$25
$25
$24
$23
$22
$22
$21
$20
$20
$20
AESS
IC
$7
$7
$7
$7
$7
$5
$5
$5
$5
$5
AESS
TC
$32
$31
$31
$30
$29
$27
$27
$26
$26
$25
AESS
Alt la
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
AESS
Alt 3
80%
80%
80%
40%
40%
40%
30%
30%
30%
15%
AESS
TCp
$0
$0
$0
-$12
-$12
-$11
-$13
-$13
-$13
-$16
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.6.8 Automatic Engine Shutdown System with Auto-Start
(AE S S_w Au to Sta rt)
We have estimated the cost of an AESS with auto-start at $2700 retail (2013$). We have
divided this value by 1.36 to arrive at a cost of $2139 (DMC, 2013$, in 2014). We have placed
this technology on the steep portion of the learning curve (curve 4) and have applied a low
complexity ICM with short term markups through 2022. The resultant technology costs,
penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-208 Costs for Automatic Engine Shutdown System with Auto-Start on Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
AESS wAutoStart
DMC
$1,369
$1,328
$1,288
$1,249
$1,212
$1,176
$1,140
$1,106
$1,084
$1,062
AESS wAutoStart
IC
$372
$371
$370
$370
$369
$294
$293
$293
$293
$293
AESS wAutoStart
TC
$1,740
$1,699
$1,659
$1,619
$1,581
$1,469
$1,434
$1,399
$1,377
$1,355
AESS wAutoStart
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
AESS wAutoStart
Alt 3
0%
0%
0%
10%
10%
10%
10%
10%
10%
15%
AESS wAutoStart
TCp
$0
$0
$0
$162
$158
$147
$143
$140
$138
$203
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.7 Electrification (strong/mild HEV, full EV)
2.11.7.1 Strong Hybrid Electric Vehicle (strong HEV)
We have estimated the cost of this technology using the costs estimated in the 2017-2025
light-duty rule for a light-duty pickup strong HEV. There we estimated the cost at $2729 (DMC,
2010$, in 2021) for a LD truck with a 5200 pound curb weight. We have then scaled upward
that value using the ratio of test weights for HD pickups in our MY2014 market file (8739
pounds) to the test weight of the 5200 pound LD truck (5500 pounds). The resultant strong
hybrid costs become $4335 (DMC, 2012$, in 2021) for HD pickups and vans. We consider this
technology to be on the steep portion of the learning curve today but on the flat portion by 2021
(curve 11) and have applied high complexity level 1 with short term markups through 2024. The
resultant technology costs are shown below for HD pickups and vans.
Table 2-209 Costs of Strong Hybrid
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Strong HEV
DMC
$4,335
$4,205
$4,079
$3,957
$3,838
$3,723
$3,648
Strong HEV
IC
$2,443
$2,435
$2,427
$2,419
$1,482
$1,478
$1,476
Strong HEV
TC
$6,779
$6,640
$6,506
$6,376
$5,320
$5,201
$5,124
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.7.2 Mild hybrid Electric Vehicle (mild HEV)
We have estimated the cost of this technology using the costs estimated in the 2017-2025
light-duty rule for a light-duty pickup mild HEV. There we estimated the cost at $983 (DMC,
2010$, in 2021) for a LD truck with a 3500 pound curb weight. We have then scaled upward
that value using the ratio of curb weights for HD pickups of 6500 pounds to the 3500 pound curb
weight. The resultant mild hybrid costs become $1894 (DMC, 2012$, in 2017) for HD pickups
and vans. We consider this technology to be on the flat portion of the learning curve (curve 6)
and have applied high complexity level 1 with short term markups through 2024. The resultant
technology costs are shown below for HD pickups and vans.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-210 Costs of Mild Hybrid
HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Mild HEV
DMC
$1,677
$1,626
$1,594
$1,562
$1,531
$1,500
$1,470
Mild HEV
IC
$1,053
$1,050
$1,048
$1,046
$643
$642
$641
Mild HEV
TC
$2,730
$2,677
$2,642
$2,608
$2,173
$2,142
$2,111
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
For vocational vehicle mild hybrids, we have scaled upward from the HD pickup and van
values using best estimates of curb weights. For vocational vehicles, we have used curb weights
of 16,000 for light HD, 25,150 for medium HD and 42,000 for heavy HD relative to a 6500
pound value for HD pickups. Scaling based on curb weight here should provide an acceptable
scaling of costs with battery and motor sizes since those are generally directly correlated with the
weight of the vehicle itself. Using these scaling factors results in costs for complete mild hybrid
systems for light, medium and heavy HD, respectively, of $4747, $7462 and $12461 (DMC,
2012$, in 2018). We consider this technology to be on the flat portion of the learning curve
(curve 12) and have applied high complexity level 1 with short term markups through 2022. The
resultant technology costs, penetration rates and total cost applied to the package are shown are
shown below.
Table 2-211 Costs for Mild Hybrid
Vocational Light HD Urban/Multipurpose Vehicles (2013$)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Mild HEV
DMC
$4,747
$4,605
$4,467
$4,333
$4,246
$4,161
$4,078
$3,996
$3,916
$3,838
Mild HEV
IC
$2,018
$2,007
$1,997
$1,987
$1,981
$1,975
$1,969
$1,963
$1,247
$1,244
Mild HEV
TC
$6,765
$6,612
$6,464
$6,320
$6,227
$6,136
$6,046
$5,959
$5,164
$5,082
Mild HEV
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Mild HEV
Alt 3
0%
0%
0%
0%
0%
0%
3%
3%
3%
6%
Mild HEV
TCp
$0
$0
$0
$0
$0
$0
$181
$179
$155
$305
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-212 Costs for Mild Hybrid
Vocational Medium HD Urban/Multipurpose Vehicles (2013$)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Mild HEV
DMC
$7,462
$7,238
$7,021
$6,810
$6,674
$6,541
$6,410
$6,282
$6,156
$6,033
Mild HEV
IC
$3,171
$3,155
$3,139
$3,124
$3,114
$3,104
$3,094
$3,085
$1,961
$1,956
Mild HEV
TC
$10,633
$10,393
$10,160
$9,934
$9,788
$9,645
$9,504
$9,367
$8,116
$7,989
Mild HEV
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Mild HEV
Alt 3
0%
0%
0%
0%
0%
0%
3%
3%
3%
6%
Mild HEV
TCp
$0
$0
$0
$0
$0
$0
$285
$281
$243
$479
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-213 Costs for Mild Hybrid
Vocational Heavy HD Urban/Multipurpose Vehicles (2013$)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Mild HEV
DMC
$12,461
$12,087
$11,725
$11,373
$11,146
$10,923
$10,704
$10,490
$10,280
$10,075
Mild HEV
IC
$5,296
$5,269
$5,242
$5,217
$5,200
$5,184
$5,168
$5,152
$3,274
$3,267
Mild HEV
TC
$17,757
$17,356
$16,967
$16,590
$16,345
$16,106
$15,872
$15,642
$13,554
$13,341
Mild HEV
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Mild HEV
Alt 3
0%
0%
0%
0%
0%
0%
3%
3%
3%
6%
Mild HEV
TCp
$0
$0
$0
$0
$0
$0
$476
$469
$407
$800
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.7.3 Hybrid electric Vehicle without Stop-Start (HEVnoSS)
We have estimated the cost of a hybrid electric system without any stop-start technology
at $8500 retail (2013$). We have divided this value by 1.36 to arrive at a cost of $6250 (DMC,
2013$, in 2021). We have placed this technology on the steep portion of the learning curve
(curve 11) and have applied high complexity level 1 ICM with short term markups through 2022
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-214 Costs for Hybrid Electric without Stop-start, Vocational Light/Medium/Heavy HD
Urban/Multipurpose Vehicles (2013$)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
HEVnoSS
DMC
$9,766
$7,813
$7,813
$6,250
$6,063
$5,881
$5,704
$5,533
$5,367
$5,260
HEVnoSS
IC
$2,914
$2,771
$2,771
$2,656
$2,643
$1,669
$1,662
$1,656
$1,650
$1,646
HEVnoSS
TC
$12,679
$10,583
$10,583
$8,906
$8,705
$7,549
$7,366
$7,189
$7,017
$6,906
HEVnoSS
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
HEVnoSS
Alt 3
0%
0%
0%
2%
2%
2%
5%
5%
5%
8%
HEVnoSS
TCp
$0
$0
$0
$178
$174
$151
$368
$359
$351
$552
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.8 Tires
2.11.8.1 Lower Rolling Resistance Tires ($/tire)
We have estimated the cost of lower rolling resistance tires based on an estimate from
TetraTech of $30 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a
cost of $22 (DMC, 2013$) but consider that cost valid in different years depending on the level
of rolling resistance. For LRR tires level 1 and 2, we consider that $22 value valid in 2014, level
3 in 2018, level 4 and level 5 (new for this FRM analysis) in 2021. We consider this technology
to be on the flat portion of the curve with LRR tires level 1 and 2 on curve 2, LRR tires level 3
on curve 12 and LRR tires level 4 and 5 on curve 13. We have applied a low complexity markup
to LRR tires levels 1 and 2 with short term markups through 2022. For LRR tires level 3, we
have applied a medium complexity markup with short term markups through 2025, for LRR tires
level 4, we have applied a medium complexity markup with short term markups through 2028,

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
and for LRR tires level 5, and we have applied a medium complexity markup with short term
markups through 2031. As a result, despite using the same DMC for each level of rolling
resistance, our tire costs can vary year-over-year for each of the 5 levels of rolling resistance
considered. The resultant costs on a per-tire basis are shown in Table 2-215. Table 2-216
through Table 2-239 show the costs per vocational vehicle, tractor or trailer depending on the
number of tires present.
Table 2-215 Costs for Lower Rolling Resistance Tires at each LRR Level (2013$/tire)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
DMC
$20
$19
$19
$18
$18
$18
$17
$17
$17
$17
LRR - level 2
DMC
$20
$19
$19
$18
$18
$18
$17
$17
$17
$17
LRR - level 3
DMC
$22
$21
$21
$20
$20
$19
$19
$19
$18
$18
LRR - level 4
DMC
$24
$23
$23
$22
$21
$21
$20
$20
$19
$19
LRR - level 5
DMC
$24
$23
$23
$22
$21
$21
$20
$20
$19
$19
LRR - level 1
IC
$4
$4
$4
$4
$4
$3
$3
$3
$3
$3
LRR - level 2
IC
$4
$4
$4
$4
$4
$3
$3
$3
$3
$3
LRR - level 3
IC
$7
$7
$7
$7
$7
$7
$7
$6
$5
$5
LRR - level 4
IC
$7
$7
$7
$7
$7
$7
$7
$7
$7
$7
LRR - level 5
IC
$7
$7
$7
$7
$7
$7
$7
$7
$7
$7
LRR - level 1
TC
$23
$23
$23
$22
$22
$21
$20
$20
$20
$20
LRR - level 2
TC
$23
$23
$23
$22
$22
$21
$20
$20
$20
$20
LRR - level 3
TC
$29
$28
$27
$27
$26
$26
$25
$25
$23
$23
LRR - level 4
TC
$31
$30
$29
$29
$28
$27
$27
$26
$26
$25
LRR - level 5
TC
$31
$30
$29
$29
$28
$27
$27
$26
$26
$25
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.8.2 Lower RR Steer Tires, Vocational Vehicles
Table 2-216 Costs for Lower Rolling Resistance Steer Tires
Vocational Light/Medium HD Urban Vehicles
(2013$/vehicle @ 2 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 2
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 3
TC
$57
$56
$55
$53
$53
$52
$51
$50
$46
$45
LRR - level 4
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 5
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
0%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$45
-$44
-$41
-$41
-$40
-$40
-$39
LRR - level 2
TCp
$0
$0
$0
$45
$44
$41
$41
$40
$40
$0
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$45
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-217 Costs for Lower Rolling Resistance Steer Tires
Vocational Light/Medium/Heavy HD Multipurpose/Regional and Heavy HD Urban Vehicles
(2013$/vehicle @ 2 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 2
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 3
TC
$57
$56
$55
$53
$53
$52
$51
$50
$46
$45
LRR - level 4
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 5
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt 3
0%
0%
0%
100%
100%
100%
0%
0%
0%
0%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
100%
100%
100%
100%
LRR - level 1
TCp
$0
$0
$0
-$45
-$44
-$41
-$41
-$40
-$40
-$39
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 3
TCp
$0
$0
$0
$53
$53
$52
$0
$0
$0
$0
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$53
$53
$52
$51
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.8.3 Lower RR Drive Tires, Vocational Vehicles
Table 2-218 Costs for Lower Rolling Resistance Drive Tires, Vocational Light HD Urban Vehicles
(2013$ @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
50%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
50%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$89
-$88
-$83
-$81
-$80
-$79
-$79
LRR - level 2
TCp
$0
$0
$0
$89
$88
$83
$81
$80
$79
$39
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$45
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-219 Costs for Lower Rolling Resistance Drive Tires, Vocational Light HD Multipurpose Vehicles
(2013$ @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$89
-$88
-$83
-$81
-$80
-$79
-$79
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 3
TCp
$0
$0
$0
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-220 Costs for Lower Rolling Resistance Drive Tires, Vocational Light HD Regional Vehicles
(2013$ @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$89
-$88
-$83
-$81
-$80
-$79
-$79
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 3
TCp
$0
$0
$0
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-221 Costs for Lower Rolling Resistance Drive Tires, Vocational Medium HD Urban Vehicles
(2013$ @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
100%
100%
100%
100%
100%
100%
50%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
50%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
-$39
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$39
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-222 Costs for Lower Rolling Resistance Drive Tires, Vocational Medium HD Multipurpose Vehicles
(2013$ @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
100%
100%
100%
50%
50%
50%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
50%
50%
50%
0%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
$0
$0
$0
-$41
-$40
-$40
-$79
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$41
$40
$40
$0
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$91
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-223 Costs for Lower Rolling Resistance Drive Tires, Vocational Medium HD Regional Vehicles
	(2013$ @ 4 tires/vehicle)	
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
100%
100%
100%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
100%
100%
100%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
$0
$0
$0
-$81
-$80
-$79
-$79
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$102
$100
$92
$91
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-224 Costs for Lower Rolling Resistance Drive Tires, Vocational Heavy HD Urban Vehicles
(2013$ @ 8 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR - level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
100%
100%
100%
100%
100%
100%
0%
LRR - level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
100%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
-$157
LRR - level 2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$157
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-225 Costs for Lower Rolling Resistance Drive Tires, Vocational Heavy HD Multipurpose Vehicles
(2013$ @ 8 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR - level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
100%
100%
100%
100%
100%
100%
0%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$178
-$175
-$166
-$163
-$160
-$159
-$157
LRR - level 2
TCp
$0
$0
$0
$178
$175
$166
$163
$160
$159
$0
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$181
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-226 Costs for Lower Rolling Resistance Drive Tires, Vocational Heavy HD Regional Vehicles
(2013$ @ 8 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR - level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 1
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR - level 2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
LRR - level 2
Alt 3
0%
0%
0%
100%
100%
100%
0%
0%
0%
0%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
100%
100%
100%
100%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$178
-$175
-$166
-$163
-$160
-$159
-$157
LRR - level 2
TCp
$0
$0
$0
$178
$175
$166
$0
$0
$0
$0
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$204
$200
$184
$181
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
2.11.8.4 Lower RR Steer Tires, Tractors
Table 2-227 Costs for Lower Rolling Resistance Steer Tires
Day Cab Low Roof & Sleeper Cab Low/Medium Roof Tractors
(2013$/vehicle @ 2 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 2
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 3
TC
$57
$56
$55
$53
$53
$52
$51
$50
$46
$45
LRR - level 4
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 1
Alt la
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
LRR - level 2
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
50%
50%
50%
35%
35%
35%
25%
25%
25%
20%
LRR - level 2
Alt 3
10%
10%
10%
50%
50%
50%
55%
55%
55%
50%
LRR - level 3
Alt 3
0%
0%
0%
10%
10%
10%
15%
15%
15%
25%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$7
-$7
-$6
-$10
-$10
-$10
-$12
LRR - level 2
TCp
$0
$0
$0
$18
$18
$17
$18
$18
$18
$16
LRR - level 3
TCp
$0
$0
$0
$5
$5
$5
$8
$8
$7
$11
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-228 Costs for Lower Rolling Resistance Steer Tires
Day & Sleeper Cab High Roof Tractors
(2013$/vehicle @ 2 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 2
TC
$47
$46
$45
$45
$44
$41
$41
$40
$40
$39
LRR - level 3
TC
$57
$56
$55
$53
$53
$52
$51
$50
$46
$45
LRR - level 4
TC
$62
$60
$59
$57
$56
$55
$53
$53
$52
$51
LRR - level 1
Alt la
70%
70%
70%
70%
70%
70%
70%
70%
70%
70%
LRR - level 2
Alt la
20%
20%
20%
20%
20%
20%
20%
20%
20%
20%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
70%
70%
70%
35%
35%
35%
15%
15%
15%
10%
LRR - level 2
Alt 3
20%
20%
20%
50%
50%
50%
60%
60%
60%
50%
LRR - level 3
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
35%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$16
-$15
-$15
-$22
-$22
-$22
-$24
LRR - level 2
TCp
$0
$0
$0
$13
$13
$12
$16
$16
$16
$12
LRR - level 3
TCp
$0
$0
$0
$5
$5
$5
$10
$10
$9
$16
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
2.11.8.5 Lower RR Drive Tires, Tractors
Table 2-229 Costs for Lower Rolling Resistance Drive Tires
Class 7 Day Cab Low Roof Tractors
(2013$/vehicle @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
LRR - level 2
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
50%
50%
50%
35%
35%
35%
25%
25%
25%
10%
LRR - level 2
Alt 3
10%
10%
10%
50%
50%
50%
65%
65%
65%
85%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$13
-$13
-$12
-$20
-$20
-$20
-$31
LRR - level 2
TCp
$0
$0
$0
$36
$35
$33
$45
$44
$44
$59
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-230 Costs for Lower Rolling Resistance Drive Tires
Class 7 Day Cab High Roof Tractors
(2013$/vehicle @ 4 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR - level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR - level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR - level 1
Alt la
70%
70%
70%
70%
70%
70%
70%
70%
70%
70%
LRR - level 2
Alt la
20%
20%
20%
20%
20%
20%
20%
20%
20%
20%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
70%
70%
70%
35%
35%
35%
15%
15%
15%
10%
LRR - level 2
Alt 3
20%
20%
20%
50%
50%
50%
60%
60%
60%
50%
LRR - level 3
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
35%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$31
-$31
-$29
-$45
-$44
-$44
-$47
LRR - level 2
TCp
$0
$0
$0
$27
$26
$25
$33
$32
$32
$24
LRR - level 3
TCp
$0
$0
$0
$11
$11
$10
$20
$20
$18
$32
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-231 Costs for Lower Rolling Resistance Drive Tires
Class 8 Day Cab Low & Sleeper Cab Low/Medium Roof Tractors
(2013$/vehicle @ 8 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR - level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 1
Alt la
50%
50%
50%
50%
50%
50%
50%
50%
50%
50%
LRR - level 2
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
50%
50%
50%
35%
35%
35%
25%
25%
25%
10%
LRR - level 2
Alt 3
10%
10%
10%
50%
50%
50%
65%
65%
65%
85%
LRR - level 3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$27
-$26
-$25
-$41
-$40
-$40
-$63
LRR - level 2
TCp
$0
$0
$0
$71
$70
$66
$90
$88
$87
$118
LRR - level 3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-232 Costs for Lower Rolling Resistance Drive Tires
Class 8 Day & Sleeper Cab High Roof Tractors
(2013$/vehicle @ 8 tires/vehicle)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR - level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR - level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR - level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR - level 1
Alt la
70%
70%
70%
70%
70%
70%
70%
70%
70%
70%
LRR - level 2
Alt la
20%
20%
20%
20%
20%
20%
20%
20%
20%
20%
LRR - level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
Alt 3
70%
70%
70%
35%
35%
35%
15%
15%
15%
10%
LRR - level 2
Alt 3
20%
20%
20%
50%
50%
50%
60%
60%
60%
50%
LRR - level 3
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
35%
LRR - level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR - level 1
TCp
$0
$0
$0
-$62
-$61
-$58
-$90
-$88
-$87
-$94
LRR - level 2
TCp
$0
$0
$0
$53
$53
$50
$65
$64
$63
$47
LRR - level 3
TCp
$0
$0
$0
$21
$21
$21
$41
$40
$37
$63
LRR - level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
2.11.8.6 Lower RR Tires, Trailers
Table 2-233 Costs for Lower Rolling Resistance Tires
Long Van, Full Aero Highway Trailers
(2013$/trailer @ 8 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR-level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
LRR-level 3
Alt la
90%
90%
90%
90%
90%
90%
90%
90%
90%
90%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$9
-$9
-$9
-$9
-$9
-$8
-$8
-$8
-$8
-$8
LRR-level 3
TCp
$11
$11
$11
-$192
-$189
-$186
-$183
-$180
-$166
-$163
LRR-level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 5
TCp
$0
$0
$0
$218
$213
$208
$203
$200
$197
$193
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-234 Costs for Lower Rolling Resistance Tires
Long Van, Partial Aero Highway Trailers
(2013$/trailer @ 8 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR-level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR-level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$178
-$175
-$172
-$169
-$166
-$157
-$155
-$152
-$151
-$150
LRR-level 3
TCp
$218
$213
$208
$0
$0
$0
$0
$0
$0
$0
LRR-level 4
TCp
$0
$0
$0
$218
$213
$208
$203
$200
$197
$193
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-235 Costs for Lower Rolling Resistance Tires
Short Van, Full Aero Highway Trailers
(2013$/trailer @ 4 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR-level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
LRR-level 3
Alt la
90%
90%
90%
90%
90%
90%
90%
90%
90%
90%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
95%
95%
95%
0%
0%
0%
0%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
95%
95%
95%
95%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$5
-$5
-$5
-$4
-$4
-$4
-$4
-$4
-$4
-$4
LRR-level 3
TCp
$6
$6
$5
-$96
-$95
-$93
-$92
-$90
-$83
-$82
LRR-level 4
TCp
$0
$0
$0
$109
$107
$104
$0
$0
$0
$0
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$101
$100
$98
$97
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-236 Costs for Lower Rolling Resistance Tires
Short Van, Partial Aero Highway Trailers
(2013$/trailer @ 4 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR-level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR-level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$89
-$88
-$86
-$85
-$83
-$79
-$77
-$76
-$75
-$75
LRR-level 3
TCp
$109
$107
$104
$0
$0
$0
$0
$0
$0
$0
LRR-level 4
TCp
$0
$0
$0
$109
$107
$104
$101
$100
$98
$97
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-237 Costs for Lower Rolling Resistance Tires
Long Van, No Aero Highway Trailers
(2013$/trailer @ 8 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR-level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR-level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$178
-$175
-$172
-$169
-$166
-$157
-$155
-$152
-$151
-$150
LRR-level 3
TCp
$218
$213
$208
$0
$0
$0
$0
$0
$0
$0
LRR-level 4
TCp
$0
$0
$0
$218
$213
$208
$203
$200
$197
$193
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-238 Costs for Lower Rolling Resistance Tires
Short Van, No Aero Highway Trailers
(2013$/trailer @ 4 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 2
TC
$94
$92
$91
$89
$88
$83
$81
$80
$79
$79
LRR-level 3
TC
$115
$112
$109
$107
$105
$103
$102
$100
$92
$91
LRR-level 4
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 5
TC
$124
$121
$118
$115
$112
$109
$107
$105
$103
$102
LRR-level 1
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt la
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
LRR-level 3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 2
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 3
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
LRR-level 4
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 2
TCp
-$89
-$88
-$86
-$85
-$83
-$79
-$77
-$76
-$75
-$75
LRR-level 3
TCp
$109
$107
$104
$0
$0
$0
$0
$0
$0
$0
LRR-level 4
TCp
$0
$0
$0
$109
$107
$104
$101
$100
$98
$97
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative
Table 2-239 Costs for Lower Rolling Resistance Tires
Non-Box Highway Trailers
(2013$/trailer @ 8 tires/trailer)
ITEM

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
LRR-level 1
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 2
TC
$187
$184
$181
$178
$175
$166
$163
$160
$159
$157
LRR-level 3
TC
$230
$224
$219
$214
$210
$207
$204
$200
$184
$181
LRR-level 4
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 5
TC
$248
$241
$236
$230
$224
$219
$214
$210
$207
$204
LRR-level 1
Alt la
40%
40%
40%
40%
40%
40%
40%
40%
40%
40%
LRR-level 2
Alt la
30%
30%
30%
30%
30%
30%
30%
30%
30%
30%
LRR-level 3
Alt la
30%
30%
30%
30%
30%
30%
30%
30%
30%
30%
LRR-level 4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
Alt 3
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
LRR-level 2
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 3
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
LRR-level 4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
LRR-level 1
TCp
-$66
-$65
-$63
-$62
-$61
-$58
-$57
-$56
-$56
-$55
LRR-level 2
TCp
-$56
-$55
-$54
-$53
-$53
-$50
-$49
-$48
-$48
-$47
LRR-level 3
TCp
$149
$146
$142
$139
$137
$135
$132
$130
$120
$118
LRR-level 4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
LRR-level 5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: TC=total cost; TCp=total cost applied to the package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.8.7 Lower RR Tires, HD Pickup & Van ($/tire)
We have estimated the costs of lower rolling resistance tires for HD pickups and vans
using the costs used in the 2017-2025 light-duty FRM. In that rule, we estimated the costs of
lower rolling resistance tires level 1 at $5/vehicle including a spare (DMC, 2010$, in all years)
and level 2 at $40/vehicle assuming no spare (DMC, 2010$, in 2021). For HD pickups and vans,
we have scaled upward both of those costs by 50 percent to account for the heavier and larger
HD tires. We consider the level 1 tires to be learned out (curve 1) and the level 2 tires to be on
the steep portion of the curve until 2021 after which it is on the flatter portion of the curve (curve
11). We have applied a low complexity markup to both with short term markups through 2018
for level 1 and through 2024 for level 2. With the exception of the 50 percent scaling factor, all
LRR tire costs for HD pickups and vans are identical to the 2017-2025 light-duty FRM. The
resultant costs are presented below.
Table 2-240 Costs for Lower Rolling Resistance Tires
HD Pickups & Vans
(2012$ @ 4 tires/vehicle)
ITEM

2021
2022
2023
2024
2025
2026
2027
LRR - level 1
DMC
$8
$8
$8
$8
$8
$8
$8
LRR - level 2
DMC
$63
$61
$59
$58
$56
$54
$53
LRR - level 1
IC
$2
$2
$2
$2
$2
$2
$2
LRR - level 2
IC
$15
$15
$15
$15
$12
$12
$12
LRR - level 1
TC
$10
$10
$10
$10
$10
$10
$10
LRR - level 2
TC
$78
$76
$74
$73
$68
$66
$65
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.8.8 Automatic Tire Inflation Systems (ATIS)
For tractors, we have estimated the cost of ATIS technology based on an estimate from
TetraTech of $1143 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a
cost of $840 (DMC, 2013$, in 2018). We consider this technology to be on the flat portion of
the learning curve (curve 12) and have applied a low complexity ICM with short term markups
through 2022. The resultant technology costs, penetration rates and total cost applied to the
package are shown below for tractors.
Table 2-241 Costs for Automatic Tire Inflation Systems
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
ATIS
DMC
$840
$815
$790
$767
$751
$736
$722
$707
$693
$679
ATIS
IC
$150
$150
$149
$149
$149
$117
$117
$117
$117
$117
ATIS
TC
$990
$964
$940
$916
$900
$853
$839
$824
$810
$796
ATIS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
ATIS
Alt 3
0%
0%
0%
20%
20%
20%
25%
25%
25%
30%
ATIS
TCp
$0
$0
$0
$183
$180
$171
$210
$206
$202
$239
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
For trailers, we have estimated the cost of this technology based on an estimate from
TetraTech of $800 (retail, 2013$). We consider this estimate to be valid for all trailers except
short vans. For short vans, we have used an estimate of $600 (retail, 2013$) since they have just
one axle. Using these estimates we divided by a 1.36 RPE to arrive at a cost of $588 (DMC,
2013$, in 2018) for all but short vans and $441 (DMC, 2013$, in 2018) for short vans. We
consider this technology to be on the flat portion of the learning curve (curve 12) and have
applied a low complexity ICM with short term markups through 2022. The resultant technology
costs, penetration rates and total cost applied to the package are shown below for trailers.
Table 2-242 Costs for Automatic Tire Inflation Systems
Long Van, Full Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
ATIS
DMC
$588
$571
$553
$537
$526
$516
$505
$495
$485
$476
ATIS
IC
$105
$105
$105
$104
$104
$82
$82
$82
$82
$82
ATIS
TC
$693
$675
$658
$641
$630
$598
$587
$577
$567
$557
ATIS
Alt la
45%
45%
45%
45%
45%
45%
45%
45%
45%
45%
ATIS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
ATIS
TCp
$347
$338
$329
$321
$315
$299
$294
$289
$284
$279
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-243 Costs for Automatic Tire Inflation Systems
Long Van, Partial Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
ATIS
DMC
$588
$571
$553
$537
$526
$516
$505
$495
$485
$476
ATIS
IC
$105
$105
$105
$104
$104
$82
$82
$82
$82
$82
ATIS
TC
$693
$675
$658
$641
$630
$598
$587
$577
$567
$557
ATIS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
ATIS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
ATIS
TCp
$659
$642
$625
$609
$599
$568
$558
$548
$539
$529
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-244 Costs for Automatic Tire Inflation Systems
Short Van, Full Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
ATIS
DMC
$441
$428
$415
$403
$395
$387
$379
$371
$364
$357
ATIS
IC
$79
$79
$78
$78
$78
$61
$61
$61
$61
$61
ATIS
TC
$520
$506
$493
$481
$473
$448
$440
$433
$425
$418
ATIS
Alt la
30%
30%
30%
30%
30%
30%
30%
30%
30%
30%
ATIS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
ATIS
TCp
$338
$329
$321
$313
$307
$291
$286
$281
$276
$272
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-245 Costs for Automatic Tire Inflation Systems
Short Van, Partial Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
ATIS
DMC
$441
$428
$415
$403
$395
$387
$379
$371
$364
$357
ATIS
IC
$79
$79
$78
$78
$78
$61
$61
$61
$61
$61
ATIS
TC
$520
$506
$493
$481
$473
$448
$440
$433
$425
$418
ATIS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
ATIS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
ATIS
TCp
$494
$481
$469
$457
$449
$426
$418
$411
$404
$397
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
2.11.8.9 Tire Pressure Monitoring System (TPMS)
We have estimated the cost of TPMS technology based on price data from Ryder.209
These price data showed a price of $94/pair of tire pressure monitoring sensors along with a
price of $65 for a repeater. Using these values as DMCs in 2013$ and applicable in 2018, we
have costed 10 sensors per class 8 tractor, 6 per class 7 tractor, 10 sensors per heavy HD
vocational vehicle, 6 per light and medium HD vocational vehicle, 8 per long van and non-box
trailer, and 4 per short van trailer. We have also included a $65 repeater for all tractors. We
consider this technology to be on the flat portion of the learning curve (curve 12) and have
applied a low complexity ICM with short term markups through 2022. The resultant technology
costs, penetration rates and total cost applied to the package are shown in the tables below.
Table 2-246 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Light/Medium HD Urban Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$282
$274
$265
$257
$252
$247
$242
$237
$233
$228
TPMS
IC
$50
$50
$50
$50
$50
$39
$39
$39
$39
$39
TPMS
TC
$332
$324
$315
$307
$302
$286
$281
$277
$272
$267
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
40%
40%
40%
55%
55%
55%
70%
TPMS
TCp
$0
$0
$0
$123
$121
$115
$155
$152
$150
$187
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-247 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Light/Medium HD Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$282
$274
$265
$257
$252
$247
$242
$237
$233
$228
TPMS
IC
$50
$50
$50
$50
$50
$39
$39
$39
$39
$39
TPMS
TC
$332
$324
$315
$307
$302
$286
$281
$277
$272
$267
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
50%
50%
50%
65%
65%
65%
80%
TPMS
TCp
$0
$0
$0
$154
$151
$143
$183
$180
$177
$214
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-248 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Light/Medium HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$282
$274
$265
$257
$252
$247
$242
$237
$233
$228
TPMS
IC
$50
$50
$50
$50
$50
$39
$39
$39
$39
$39
TPMS
TC
$332
$324
$315
$307
$302
$286
$281
$277
$272
$267
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
60%
60%
60%
75%
75%
75%
90%
TPMS
TCp
$0
$0
$0
$184
$181
$172
$211
$207
$204
$240
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-249 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Heavy HD Urban Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$535
$519
$503
$488
$479
$469
$460
$450
$441
$433
TPMS
IC
$95
$95
$95
$95
$95
$75
$74
$74
$74
$74
TPMS
TC
$630
$614
$598
$583
$573
$543
$534
$525
$516
$507
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
40%
40%
40%
55%
55%
55%
70%
TPMS
TCp
$0
$0
$0
$233
$229
$217
$294
$289
$284
$355
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-250 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Heavy HD Multipurpose Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$535
$519
$503
$488
$479
$469
$460
$450
$441
$433
TPMS
IC
$95
$95
$95
$95
$95
$75
$74
$74
$74
$74
TPMS
TC
$630
$614
$598
$583
$573
$543
$534
$525
$516
$507
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
50%
50%
50%
65%
65%
65%
80%
TPMS
TCp
$0
$0
$0
$292
$287
$272
$347
$341
$335
$405
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-251 Costs for Tire Pressure Monitoring Systems (TPMS)
Vocational Heavy HD Regional Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$535
$519
$503
$488
$479
$469
$460
$450
$441
$433
TPMS
IC
$95
$95
$95
$95
$95
$75
$74
$74
$74
$74
TPMS
TC
$630
$614
$598
$583
$573
$543
$534
$525
$516
$507
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
60%
60%
60%
75%
75%
75%
90%
TPMS
TCp
$0
$0
$0
$350
$344
$326
$401
$394
$387
$456
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-252 Costs for Tire Pressure Monitoring Systems (TPMS)
Class 7 Day Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$347
$337
$326
$317
$310
$304
$298
$292
$286
$281
TPMS
IC
$62
$62
$62
$62
$61
$48
$48
$48
$48
$48
TPMS
TC
$409
$398
$388
$378
$372
$352
$346
$340
$334
$329
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
20%
20%
20%
50%
50%
50%
70%
TPMS
TCp
$0
$0
$0
$76
$74
$70
$173
$170
$167
$230
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-253 Costs for Tire Pressure Monitoring Systems (TPMS)
Class 8 Day & Sleeper Cab Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$535
$519
$503
$488
$479
$469
$460
$450
$441
$433
TPMS
IC
$95
$95
$95
$95
$95
$75
$74
$74
$74
$74
TPMS
TC
$630
$614
$598
$583
$573
$543
$534
$525
$516
$507
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
0%
0%
0%
20%
20%
20%
50%
50%
50%
70%
TPMS
TCp
$0
$0
$0
$117
$115
$109
$267
$262
$258
$355
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-254 Costs for Tire Pressure Monitoring Systems (TPMS)
Long Van, No Aero and Non-Box Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$376
$365
$354
$343
$336
$330
$323
$317
$310
$304
TPMS
IC
$67
$67
$67
$67
$67
$52
$52
$52
$52
$52
TPMS
TC
$443
$432
$421
$410
$403
$382
$375
$369
$362
$356
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
TPMS
TCp
$421
$410
$400
$389
$383
$363
$357
$350
$344
$338
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative
Table 2-255 Costs for Tire Pressure Monitoring Systems (TPMS)
Short Van, No Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
TPMS
DMC
$188
$182
$177
$172
$168
$165
$161
$158
$155
$152
TPMS
IC
$34
$33
$33
$33
$33
$26
$26
$26
$26
$26
TPMS
TC
$222
$216
$210
$205
$201
$191
$188
$184
$181
$178
TPMS
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
TPMS
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
TPMS
TCp
$210
$205
$200
$195
$191
$181
$178
$175
$172
$169
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the
package; alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.9 Aerodynamic Improvements (Aero)
The agencies' estimates for cost of tractor aero features are based the work done by ICF
in support of the Phase 1 HD rules. For trailers, we have based our estimates on the work
presented in the ICCT trailer technology report.210
2.11.9.1 Aero Improvements, Day Cab Low Roof Tractors
For low roof day cab tractors, Aero Bin 2 costs are estimated at $1020, Bin 3 at $2059
and Bin 4 at $2625 (all are DMC, in 2013$, and applicable in 2014). We consider Bin 2
technologies to be beyond the effects of learning (curve 1), Bin 3 technologies to be on the flat
portion of the curve (curve 2) and Bin 4 technologies to be on the steep portion of the curve
(curve 4). We have applied a low complexity ICMs to each with short term markups through
2022. The resultant technology costs, penetration rates and total cost applied to the package are
shown below.
Table 2-256 Costs of Aero Technologies
Day Cab Low Roof Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin2
DMC
$1,020
$1,020
$1,020
$1,020
$1,020
$1,020
$1,020
$1,020
$1,020
$1,020
Aero Bin3
DMC
$1,823
$1,787
$1,751
$1,716
$1,681
$1,648
$1,615
$1,583
$1,567
$1,551
Aero Bint
DMC
$1,680
$1,630
$1,581
$1,534
$1,488
$1,443
$1,400
$1,358
$1,331
$1,304
Aero Bin2
IC
$182
$182
$182
$182
$182
$143
$143
$143
$143
$143
Aero Bin3
IC
$364
$364
$363
$363
$362
$286
$286
$285
$285
$285
Aero Bin4
IC
$456
$455
$455
$454
$454
$360
$360
$360
$360
$360
Aero Bin2
TC
$1,201
$1,201
$1,201
$1,201
$1,201
$1,162
$1,162
$1,162
$1,162
$1,162
Aero Bin3
TC
$2,187
$2,150
$2,114
$2,079
$2,044
$1,934
$1,901
$1,868
$1,852
$1,836
Aero Bint
TC
$2,136
$2,085
$2,036
$1,988
$1,941
$1,803
$1,760
$1,718
$1,690
$1,663
Aero Bin2
Alt la
90%
90%
90%
90%
90%
90%
90%
90%
90%
90%
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bint
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
Alt 3
90%
90%
90%
95%
95%
95%
80%
80%
80%
50%
Aero Bin3
Alt 3
0%
0%
0%
5%
5%
5%
20%
20%
20%
50%
Aero Bint
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
TCp
$0
$0
$0
$60
$60
$58
-$116
-$116
-$116
-$465
Aero Bin3
TCp
$0
$0
$0
$104
$102
$97
$380
$374
$370
$918
Aero Bin4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.9.2 Aero Improvements, Day Cab High Roof Tractors
For high roof day cab tractors, Aero Bin 3 costs are estimated at $1046, Bin 4 at $2086,
Bin 5 at $2660, Bin 6 at $3234 and Bin 7 at $3807 (all are DMC, in 2013$, and applicable in
2014; note that the table below makes clear that we do not project use of aero improvements
above Bin 5). We consider Bin 3 technologies to be on the flat portion of the curve (curve 2) and
Bin 4 through 7 technologies to be on the steep portion of the curve (curve 4). We have applied
a low complexity ICMs to Bins 3 and 4 with short term markups through 2022. We have applied
medium complexity ICMs to Bins 5 through 7 with short term markups through 2025. The

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-257 Costs of Aero Technologies
Day Cab High Roof Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin3
DMC
$926
$908
$890
$872
$854
$837
$821
$804
$796
$788
Aero Bin4
DMC
$1,335
$1,295
$1,256
$1,219
$1,182
$1,147
$1,112
$1,079
$1,057
$1,036
Aero Bin5
DMC
$1,702
$1,651
$1,602
$1,554
$1,507
$1,462
$1,418
$1,375
$1,348
$1,321
Aero Bin6
DMC
$2,069
$2,007
$1,947
$1,889
$1,832
$1,777
$1,724
$1,672
$1,639
$1,606
Aero Bin7
DMC
$2,437
$2,364
$2,293
$2,224
$2,157
$2,092
$2,030
$1,969
$1,929
$1,891
Aero Bin3
IC
$185
$185
$185
$184
$184
$145
$145
$145
$145
$145
Aero Bin4
IC
$362
$362
$361
$361
$360
$286
$286
$286
$286
$286
Aero Bin5
IC
$756
$753
$750
$748
$746
$743
$741
$739
$554
$553
Aero Bin6
IC
$919
$915
$912
$909
$907
$904
$901
$898
$673
$672
Aero Bin7
IC
$1,082
$1,078
$1,074
$1,071
$1,067
$1,064
$1,061
$1,058
$793
$792
Aero Bin3
TC
$1,112
$1,093
$1,074
$1,056
$1,039
$983
$966
$949
$941
$933
Aero Bin4
TC
$1,697
$1,657
$1,618
$1,579
$1,542
$1,433
$1,398
$1,365
$1,343
$1,322
Aero Bin5
TC
$2,458
$2,404
$2,352
$2,302
$2,253
$2,205
$2,159
$2,114
$1,902
$1,874
Aero Bin6
TC
$2,988
$2,923
$2,860
$2,798
$2,739
$2,681
$2,625
$2,571
$2,312
$2,278
Aero Bin7
TC
$3,518
$3,441
$3,367
$3,295
$3,224
$3,156
$3,091
$3,027
$2,722
$2,682
Aero Bin3
Alt la
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
Aero Bin4
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
Aero Bin5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
Alt 3
80%
80%
80%
60%
60%
60%
40%
40%
40%
30%
Aero Bin4
Alt 3
10%
10%
10%
35%
35%
35%
40%
40%
40%
30%
Aero Bin5
Alt 3
0%
0%
0%
5%
5%
5%
20%
20%
20%
40%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
TCp
$0
$0
$0
-$211
-$208
-$197
-$386
-$380
-$376
-$467
Aero Bin4
TCp
$0
$0
$0
$395
$386
$358
$419
$409
$403
$264
Aero Bin5
TCp
$0
$0
$0
$115
$113
$110
$432
$423
$380
$750
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.9.3 Aero Improvements, Sleeper Cab Low/Mid Roof Tractors
For low and mid roof sleeper cab tractors, Aero Bin 2 costs are estimated at $1244, Bin 3
at $2356 and Bin 4 at $3003 (all are DMC, in 2013$, and applicable in 2014). We consider Bin
2 technologies to be beyond the effects of learning (curve 1), Bin 3 technologies to be on the flat
portion of the curve (curve 2) and Bin 4 technologies to be on the steep portion of the curve
(curve 4). We have applied a low complexity ICMs to each with short term markups through
2022. The resultant technology costs, penetration rates and total cost applied to the package are
shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-258 Costs of Aero Technologies
Sleeper Cab Low/Mid Roof Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin2
DMC
$1,244
$1,244
$1,244
$1,244
$1,244
$1,244
$1,244
$1,244
$1,244
$1,244
Aero Bin3
DMC
$2,085
$2,044
$2,003
$1,963
$1,923
$1,885
$1,847
$1,810
$1,792
$1,774
Aero Bin4
DMC
$1,922
$1,864
$1,808
$1,754
$1,702
$1,651
$1,601
$1,553
$1,522
$1,492
Aero Bin2
IC
$222
$222
$222
$222
$222
$174
$174
$174
$174
$174
Aero Bin3
IC
$417
$416
$416
$415
$415
$327
$327
$327
$326
$326
Aero Bin4
IC
$522
$521
$520
$519
$519
$412
$412
$412
$412
$411
Aero Bin2
TC
$1,466
$1,466
$1,466
$1,466
$1,466
$1,419
$1,419
$1,419
$1,419
$1,419
Aero Bin3
TC
$2,502
$2,460
$2,418
$2,378
$2,338
$2,212
$2,174
$2,137
$2,119
$2,101
Aero Bin4
TC
$2,444
$2,385
$2,329
$2,274
$2,220
$2,063
$2,013
$1,965
$1,933
$1,903
Aero Bin2
Alt la
90%
90%
90%
90%
90%
90%
90%
90%
90%
90%
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
Alt 3
90%
90%
90%
90%
90%
90%
90%
90%
90%
60%
Aero Bin3
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
40%
Aero Bin4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
-$426
Aero Bin3
TCp
$0
$0
$0
$119
$117
$111
$217
$214
$212
$840
Aero Bin4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.9.4 Aero Improvements, Sleeper Cab High Roof Tractors
For high roof sleeper cab tractors, Aero Bin 3 costs are estimated at $1413, Bin 4 at
$2423, Bin 5 at $3089, Bin 6 at $3755 and Bin 7 at $4422 (all are DMC, in 2013$, and
applicable in 2014; note that the table below makes clear that we do not project use of aero
improvements above Bin 5). We consider Bin 3 technologies to be on the flat portion of the
curve (curve 2) and Bin 4 through 7 technologies to be on the steep portion of the curve (curve
4). We have applied a low complexity ICMs to Bins 3 and 4 with short term markups through
2022. We have applied medium complexity ICMs to Bins 5 through 7 with short term markups
through 2025. The resultant technology costs, penetration rates and total cost applied to the
package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-259 Costs of Aero Technologies
Sleeper Cab High Roof Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin3
DMC
$1,251
$1,226
$1,201
$1,177
$1,154
$1,131
$1,108
$1,086
$1,075
$1,064
Aero Bin4
DMC
$1,551
$1,504
$1,459
$1,415
$1,373
$1,332
$1,292
$1,253
$1,228
$1,203
Aero Bin5
DMC
$1,977
$1,918
$1,860
$1,804
$1,750
$1,698
$1,647
$1,597
$1,565
$1,534
Aero Bin6
DMC
$2,403
$2,331
$2,261
$2,194
$2,128
$2,064
$2,002
$1,942
$1,903
$1,865
Aero Bin7
DMC
$2,830
$2,745
$2,663
$2,583
$2,505
$2,430
$2,357
$2,286
$2,241
$2,196
Aero Bin3
IC
$250
$250
$249
$249
$249
$196
$196
$196
$196
$196
Aero Bin4
IC
$421
$420
$420
$419
$418
$333
$332
$332
$332
$332
Aero Bin5
IC
$878
$875
$872
$869
$866
$863
$861
$858
$643
$642
Aero Bin6
IC
$1,067
$1,063
$1,060
$1,056
$1,053
$1,050
$1,046
$1,043
$782
$781
Aero Bin7
IC
$1,256
$1,252
$1,248
$1,244
$1,240
$1,236
$1,232
$1,229
$921
$919
Aero Bin3
TC
$1,501
$1,475
$1,450
$1,426
$1,402
$1,327
$1,304
$1,282
$1,271
$1,260
Aero Bin4
TC
$1,971
$1,924
$1,879
$1,834
$1,791
$1,664
$1,624
$1,585
$1,560
$1,535
Aero Bin5
TC
$2,855
$2,792
$2,732
$2,673
$2,616
$2,561
$2,508
$2,456
$2,209
$2,176
Aero Bin6
TC
$3,470
$3,395
$3,321
$3,250
$3,181
$3,114
$3,048
$2,985
$2,685
$2,646
Aero Bin7
TC
$4,086
$3,997
$3,910
$3,826
$3,745
$3,666
$3,589
$3,515
$3,162
$3,115
Aero Bin3
Alt la
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
Aero Bin4
Alt la
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
Aero Bin5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
Alt 3
80%
80%
80%
60%
60%
60%
40%
40%
40%
20%
Aero Bin4
Alt 3
10%
10%
10%
30%
30%
30%
40%
40%
40%
30%
Aero Bin5
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
50%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
TCp
$0
$0
$0
-$285
-$280
-$265
-$522
-$513
-$508
-$756
Aero Bin4
TCp
$0
$0
$0
$367
$358
$333
$487
$476
$468
$307
Aero Bin5
TCp
$0
$0
$0
$267
$262
$256
$502
$491
$442
$1,088
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.9.5 Aero Improvements, Trailers
For long van trailers, Aero Bin 3 costs are based on and ICCT estimate of $700 (retail,
2013$), Bin 4 costs are based on an ICCT estimate of $1000 (retail, 2013$), Bin 5 costs are
based on an ICCT estimate of $1600 (retail, 2013$), Bin 6 costs are based on an ICCT estimate
of $1900 (retail, 2013$), Bin 7 costs are based on an ICCT estimate of $2200 (retail, 2013$), and
Bin 8 costs are based on an ICCT estimate of $2900 (retail, 2013$). We have used these costs
and divided by a 1.36 RPE to arrive at direct manufacturing costs of $515, $735, $1176, $1397,
$1617 and $2132 for Bins 3 through 8, respectively (all are DMC, in 2013$, applicable in 2014).
We consider each of these technologies to be on the flat portion of the learning curve (curve 2)
and have applied low complexity ICMs with short term markups through 2018. The resultant
technology costs, penetration rates and total cost applied to the package are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-260 Costs of Aero Technologies
Long Van, Full Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin3
DMC
$456
$447
$438
$429
$420
$412
$404
$396
$392
$388
Aero Bin4
DMC
$651
$638
$625
$613
$600
$588
$577
$565
$559
$554
Aero Bin5
DMC
$1,042
$1,021
$1,000
$980
$961
$941
$923
$904
$895
$886
Aero Bin6
DMC
$1,237
$1,212
$1,188
$1,164
$1,141
$1,118
$1,096
$1,074
$1,063
$1,052
Aero Bin7
DMC
$1,432
$1,403
$1,375
$1,348
$1,321
$1,294
$1,269
$1,243
$1,231
$1,218
Aero Bin8
DMC
$1,888
$1,850
$1,813
$1,777
$1,741
$1,706
$1,672
$1,639
$1,622
$1,606
Aero Bin3
IC
$91
$72
$72
$72
$72
$71
$71
$71
$71
$71
Aero Bin4
IC
$130
$102
$102
$102
$102
$102
$102
$102
$102
$102
Aero Bin5
IC
$208
$164
$164
$164
$163
$163
$163
$163
$163
$163
Aero Bin6
IC
$247
$195
$194
$194
$194
$194
$194
$194
$194
$194
Aero Bin7
IC
$286
$225
$225
$225
$225
$225
$224
$224
$224
$224
Aero Bin8
IC
$377
$297
$297
$296
$296
$296
$296
$296
$296
$295
Aero Bin3
TC
$547
$518
$509
$500
$492
$483
$475
$467
$463
$459
Aero Bin4
TC
$781
$740
$727
$715
$703
$690
$679
$667
$661
$656
Aero Bin5
TC
$1,250
$1,185
$1,164
$1,144
$1,124
$1,105
$1,086
$1,067
$1,058
$1,049
Aero Bin6
TC
$1,484
$1,407
$1,382
$1,358
$1,335
$1,312
$1,289
$1,267
$1,257
$1,246
Aero Bin7
TC
$1,718
$1,629
$1,600
$1,573
$1,546
$1,519
$1,493
$1,467
$1,455
$1,443
Aero Bin8
TC
$2,265
$2,147
$2,110
$2,073
$2,037
$2,002
$1,968
$1,934
$1,918
$1,902
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt la
40%
40%
40%
40%
40%
40%
40%
40%
40%
40%
Aero Bin5
Alt la
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt 3
95%
95%
95%
0%
0%
0%
0%
0%
0%
0%
Aero Bin5
Alt 3
0%
0%
0%
95%
95%
95%
0%
0%
0%
0%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
95%
95%
95%
30%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
70%
Aero Bin8
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin4
TCp
$430
$407
$400
-$286
-$281
-$276
-$271
-$267
-$265
-$262
Aero Bin5
TCp
-$62
-$59
-$58
$1,029
$1,012
$994
-$54
-$53
-$53
-$52
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$1,225
$1,204
$1,194
$374
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$1,010
Aero Bin8
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-261 Costs of Aero Technologies
Long Van, Partial Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin3
DMC
$456
$447
$438
$429
$420
$412
$404
$396
$392
$388
Aero Bin4
DMC
$651
$638
$625
$613
$600
$588
$577
$565
$559
$554
Aero Bin5
DMC
$1,042
$1,021
$1,000
$980
$961
$941
$923
$904
$895
$886
Aero Bin6
DMC
$1,237
$1,212
$1,188
$1,164
$1,141
$1,118
$1,096
$1,074
$1,063
$1,052
Aero Bin7
DMC
$1,432
$1,403
$1,375
$1,348
$1,321
$1,294
$1,269
$1,243
$1,231
$1,218
Aero Bin8
DMC
$1,888
$1,850
$1,813
$1,777
$1,741
$1,706
$1,672
$1,639
$1,622
$1,606
Aero Bin3
IC
$91
$72
$72
$72
$72
$71
$71
$71
$71
$71
Aero Bin4
IC
$130
$102
$102
$102
$102
$102
$102
$102
$102
$102
Aero Bin5
IC
$208
$164
$164
$164
$163
$163
$163
$163
$163
$163
Aero Bin6
IC
$247
$195
$194
$194
$194
$194
$194
$194
$194
$194
Aero Bin7
IC
$286
$225
$225
$225
$225
$225
$224
$224
$224
$224
Aero Bin8
IC
$377
$297
$297
$296
$296
$296
$296
$296
$296
$295
Aero Bin3
TC
$547
$518
$509
$500
$492
$483
$475
$467
$463
$459
Aero Bin4
TC
$781
$740
$727
$715
$703
$690
$679
$667
$661
$656
Aero Bin5
TC
$1,250
$1,185
$1,164
$1,144
$1,124
$1,105
$1,086
$1,067
$1,058
$1,049
Aero Bin6
TC
$1,484
$1,407
$1,382
$1,358
$1,335
$1,312
$1,289
$1,267
$1,257
$1,246
Aero Bin7
TC
$1,718
$1,629
$1,600
$1,573
$1,546
$1,519
$1,493
$1,467
$1,455
$1,443
Aero Bin8
TC
$2,265
$2,147
$2,110
$2,073
$2,037
$2,002
$1,968
$1,934
$1,918
$1,902
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt 3
95%
95%
95%
95%
95%
95%
95%
95%
95%
95%
Aero Bin5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin4
TCp
$742
$703
$691
$679
$667
$656
$645
$634
$628
$623
Aero Bin5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-262 Costs of Aero Technologies
Short Van, Full Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin2
DMC
$456
$447
$438
$429
$420
$412
$404
$396
$392
$388
Aero Bin3
DMC
$911
$893
$875
$858
$841
$824
$807
$791
$783
$775
Aero Bin4
DMC
$1,107
$1,084
$1,063
$1,042
$1,021
$1,000
$980
$961
$951
$942
Aero Bin5
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
IC
$91
$72
$72
$72
$72
$71
$71
$71
$71
$71
Aero Bin3
IC
$182
$143
$143
$143
$143
$143
$143
$143
$143
$143
Aero Bin4
IC
$221
$174
$174
$174
$174
$174
$173
$173
$173
$173
Aero Bin5
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
TC
$547
$518
$509
$500
$492
$483
$475
$467
$463
$459
Aero Bin3
TC
$1,093
$1,036
$1,018
$1,001
$984
$967
$950
$934
$926
$918
Aero Bin4
TC
$1,328
$1,259
$1,237
$1,215
$1,194
$1,174
$1,154
$1,134
$1,124
$1,115
Aero Bin5
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
Alt la
5%
5%
5%
5%
5%
5%
5%
5%
5%
5%
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
Alt 3
5%
5%
5%
95%
95%
95%
0%
0%
0%
0%
Aero Bin3
Alt 3
0%
0%
0%
0%
0%
0%
95%
95%
95%
30%
Aero Bin4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
60%
Aero Bin5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
10%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
TCp
$0
$0
$0
$450
$443
$435
-$24
-$23
-$23
-$23
Aero Bin3
TCp
$0
$0
$0
$0
$0
$0
$903
$887
$880
$275
Aero Bin4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$669
Aero Bin5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-263 Costs of Aero Technologies
Short Van, Partial Aero Trailers (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Aero Bin2
DMC
$456
$447
$438
$429
$420
$412
$404
$396
$392
$388
Aero Bin3
DMC
$911
$893
$875
$858
$841
$824
$807
$791
$783
$775
Aero Bin4
DMC
$1,107
$1,084
$1,063
$1,042
$1,021
$1,000
$980
$961
$951
$942
Aero Bin5
DMC
$1,107
$1,084
$1,063
$1,042
$1,021
$1,000
$980
$961
$951
$942
Aero Bin6
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
DMC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
IC
$91
$72
$72
$72
$72
$71
$71
$71
$71
$71
Aero Bin3
IC
$182
$143
$143
$143
$143
$143
$143
$143
$143
$143
Aero Bin4
IC
$221
$174
$174
$174
$174
$174
$173
$173
$173
$173
Aero Bin5
IC
$221
$174
$174
$174
$174
$174
$173
$173
$173
$173
Aero Bin6
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
IC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
TC
$547
$518
$509
$500
$492
$483
$475
$467
$463
$459
Aero Bin3
TC
$1,093
$1,036
$1,018
$1,001
$984
$967
$950
$934
$926
$918
Aero Bin4
TC
$1,328
$1,259
$1,237
$1,215
$1,194
$1,174
$1,154
$1,134
$1,124
$1,115
Aero Bin5
TC
$1,328
$1,259
$1,237
$1,215
$1,194
$1,174
$1,154
$1,134
$1,124
$1,115
Aero Bin6
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
TC
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin2
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin3
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin5
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
Alt 3
0%
0%
0%
95%
95%
95%
95%
95%
95%
95%
Aero Bin3
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin4
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin5
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin6
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin7
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin8
Alt 3
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Aero Bin2
TCp
$0
$0
$0
$475
$467
$459
$451
$444
$440
$436
Aero Bin3
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin4
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin5
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin6
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin7
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Aero Bin8
TCp
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.9.6 Aero Improvements, HD Pickups and Vans
For HD pickups and vans, we have based our aero improvement costs on values used in
our light-duty 2017-2025 final rule. Using those values updated to 2012$ results in costs for
aero 1 (passive aero treatments) and active aero treatments of $47 and $142 (both are DMC, in
2012$, in 2015). Note that the aero 2 costs are the passive aero 1 plus the active aero costs. We
consider both of these technologies to be on the flat portion of the learning curve (curve 8) and,
to aero 1, have applied low complexity markups with near term markups through 2018 and, to
active aero, and have applied medium complexity markups with near term markups through
2024. The resultant costs for HD pickups and vans are shown below for aero 1 and active aero
and then for aero 2 (the two combined, passive+active aero).
Table 2-264 Costs for Passive Aero Treatments - Aero 1
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Aero 1 - passive aero
DMC
$42
$41
$40
$39
$38
$38
$38
Aero 1 - passive aero
IC
$9
$9
$9
$9
$9
$9
$9
Aero 1 - passive aero
TC
$51
$50
$49
$48
$47
$47
$47
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-265 Costs for Active Aero Treatments
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Aero 2 - active aero
DMC
$125
$122
$120
$118
$115
$114
$113
Aero 2 - active aero
IC
$54
$54
$54
$54
$40
$40
$40
Aero 2 - active aero
TC
$179
$177
$174
$172
$156
$154
$153
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
Table 2-266 Costs for Aero 2 (passive plus active aero)
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Aero 2 - active aero
DMC
$166
$163
$160
$157
$154
$152
$151
Aero 2 - active aero
IC
$63
$63
$63
$63
$50
$49
$49
Aero 2 - active aero
TC
$230
$227
$223
$220
$203
$201
$200
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.10 Other Technologies
2.11.10.1 Advanced Cruise Controls, Tractors
We have estimated the cost of this technology based on an estimate from TetraTech of
$1100 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a cost of $809
(DMC, 2013$, in 2018). We consider this technology to be on the flat portion of the learning
curve (curve 12) and have applied a low complexity ICM with short term markups through 2022.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
The resultant technology costs, penetration rates and total cost applied to the package are shown
below.
Table 2-267 Costs for Advanced Cruise Controls
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Advanced cruise control
DMC
$809
$785
$761
$738
$723
$709
$695
$681
$667
$654
Advanced cruise control
IC
$144
$144
$144
$143
$143
$113
$113
$112
$112
$112
Advanced cruise control
TC
$953
$929
$905
$882
$867
$822
$807
$793
$780
$766
Advanced cruise control
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Advanced cruise control
Alt 3
0%
0%
0%
20%
20%
20%
40%
40%
40%
40%
Advanced cruise control
TCp
$0
$0
$0
$176
$173
$164
$323
$317
$312
$307
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.10.2 Improved Accessories
For vocational vehicles, we have estimated the cost of this technology based on an
estimate from TIAX of $530 (retail) for light HD, $1000 for medium HD and $2000 for heavy
HD vocational vehicles. These estimates include costs of upgrading to a 42 Volt electrical
system, electric power steering and electric air conditioning. Using these estimates, we divided
by a 1.36 RPE to arrive at cost of $390, $735 and $1471, respectively (DMC, 2013$, in 2018).
We consider this technology to be on the flat portion of the learning curve (curve 12) and have
applied a low complexity ICM with short term markups through 2022. The resultant technology
costs, penetration rates and total cost applied to the package are shown below.
Table 2-268 Costs for Improved Accessories
Vocational Light HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved accessories
DMC
$390
$378
$367
$356
$349
$342
$335
$328
$322
$315
Improved accessories
IC
$70
$69
$69
$69
$69
$54
$54
$54
$54
$54
Improved accessories
TC
$459
$447
$436
$425
$418
$396
$389
$382
$376
$369
Improved accessories
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved accessories
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
15%
Improved accessories
TCp
$0
$0
$0
$21
$21
$20
$39
$38
$38
$55
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
Table 2-269 Costs for Improved Accessories
Vocational Medium HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved accessories
DMC
$735
$713
$692
$671
$658
$645
$632
$619
$607
$594
Improved accessories
IC
$131
$131
$131
$130
$130
$102
$102
$102
$102
$102
Improved accessories
TC
$867
$844
$822
$801
$788
$747
$734
$721
$709
$697
Improved accessories
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved accessories
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
15%
Improved accessories
TCp
$0
$0
$0
$40
$39
$37
$73
$72
$71
$104
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-270 Costs for Improved Accessories
Vocational Heavy HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved accessories
DMC
$1,471
$1,426
$1,384
$1,342
$1,315
$1,289
$1,263
$1,238
$1,213
$1,189
Improved accessories
IC
$262
$262
$261
$261
$260
$205
$205
$205
$204
$204
Improved accessories
TC
$1,733
$1,688
$1,645
$1,603
$1,576
$1,494
$1,468
$1,443
$1,418
$1,393
Improved accessories
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved accessories
Alt 3
0%
0%
0%
5%
5%
5%
10%
10%
10%
15%
Improved accessories
TCp
$0
$0
$0
$80
$79
$75
$147
$144
$142
$209
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
For tractors, we have estimated the cost of this technology based on an estimate from
TetraTech of $350 (retail, 2013$). Using that estimate we divided by a 1.36 RPE to arrive at a
cost of $257 (DMC, 2013$, in 2018). We consider this technology to be on the flat portion of
the learning curve (curve 12) and have applied a low complexity ICM with short term markups
through 2022. The resultant technology costs, penetration rates and total cost applied to the
package are shown below for tractors.
Table 2-271 Costs for Improved Accessories
Tractors (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Improved accessories
DMC
$257
$250
$242
$235
$230
$226
$221
$217
$212
$208
Improved accessories
IC
$46
$46
$46
$46
$46
$36
$36
$36
$36
$36
Improved accessories
TC
$303
$295
$288
$281
$276
$261
$257
$252
$248
$244
Improved accessories
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Improved accessories
Alt 3
0%
0%
0%
10%
10%
10%
20%
20%
20%
30%
Improved accessories
TCp
$0
$0
$0
$28
$28
$26
$51
$50
$50
$73
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
For HD pickups and vans, we have estimated the costs for two levels of improved
accessories based on estimates presented in the light-duty 2017-2025 final rule. In that rule, we
estimated the costs of IACC1 and IACC2 at $73 and $118, respectively (both are DMC, 2009$,
in 2015). With updates to 2012$, these costs become $77 and $124, respectively (both are DMC,
2012$, in 2015). Note that IACC2 includes IACC1. We consider these technologies to be on the
flat portion of the learning curve (curve 8) and have applied low complexity markups with near
term markups through 2018. The resultant cost for both are shown below.
Table 2-272 Costs for Improved Accessories
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Improved accessories 1 (IACC1)
DMC
$67
$66
$64
$63
$62
$61
$61
Improved accessories 1 (IACC2)
DMC
$109
$106
$104
$102
$100
$99
$98
Improved accessories 1 (IACC1)
IC
$15
$15
$15
$15
$15
$15
$15
Improved accessories 1 (IACC2)
IC
$24
$24
$24
$24
$24
$24
$24
Improved accessories 1 (IACC1)
TC
$82
$80
$79
$78
$77
$76
$75
Improved accessories 1 (IACC2)
TC
$132
$130
$128
$126
$124
$123
$122
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.11.10.3 Weight Reduction, Vocational Vehicles
We have estimated the cost of a 200 pound weight reduction on vocational vehicles at
$4/pound (retail, 2013$). Using that cost we have divided by a 1.36 RPE to arrive at costs of
$588 (DMC, in 2013$, applicable in 2021). We consider this weight reduction level to be on the
flat portion of the learning curve (curve 13) and have applied low complexity ICMs with short
term markups through 2022. We have applied the 200 pound weight reduction level to light and
medium HD vocational vehicles. The resultant technology costs, penetration rates and total cost
applied to the package are shown below.
Table 2-273 Costs for a 200 Pound Weight Reduction
Vocational Light/Medium HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Weight reduction, 200 lbs
DMC
$645
$625
$606
$588
$571
$553
$537
$526
$516
$505
Weight reduction, 200 lbs
IC
$106
$105
$105
$105
$105
$82
$82
$82
$82
$82
Weight reduction, 200 lbs
TC
$750
$731
$712
$693
$675
$636
$619
$608
$598
$587
Weight reduction, 200 lbs
Alt la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Weight reduction, 200 lbs
Alt 3
0%
0%
0%
10%
10%
10%
30%
30%
30%
50%
Weight reduction, 200 lbs
TCp
$0
$0
$0
$69
$68
$64
$186
$182
$179
$294
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
We have estimated the cost of weight reduction from use of aluminum wheels based on
the aluminum steer wheel technology discussed in the Phase 1 rules. That technology was
estimated at $459 for two wheels (DMC, 2008$, in 2014). With updates to 2013$, we estimate
the costs at $494 (DMC, 2013$, in 2014). We consider this technology to be on the flat portion
of the learning curve (curve 2) and have applied a low complexity ICM with short term markups
through 2022. The resultant technology costs, penetration rates and total cost applied to the
package are shown below. We apply this technology to heavy HD vocational vehicles having 10
wheels per vehicle.
Table 2-274 Costs for Weight Reduction via use of Aluminum Wheels
Vocational Heavy HD Vehicles (2013$)
TECHNOLOGY

2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Weight reduction, A1 wheels
DMC
$2,188
$2,144
$2,102
$2,060
$2,018
$1,978
$1,938
$1,900
$1,881
$1,862
Weight reduction, A1 wheels
IC
$437
$437
$436
$436
$435
$343
$343
$343
$343
$342
Weight reduction, A1 wheels
TC
$2,626
$2,581
$2,538
$2,495
$2,453
$2,321
$2,281
$2,242
$2,223
$2,204
Weight reduction, A1 wheels
Alt
la
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Weight reduction, A1 wheels
Alt 3
0%
0%
0%
10%
10%
10%
30%
30%
30%
50%
Weight reduction, A1 wheels
TCp
$0
$0
$0
$250
$245
$232
$684
$673
$667
$1,102
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost; TCp=total cost applied to the package;
alt=alternative
2.11.10.4 Weight Reduction in HD Pickups and Vans
For this rule, we are estimating weight reduction costs for HD pickups and vans using the
same cost curve used in support of the 2017-2025 light-duty GHG/CAFE FRM. That curve can
be expressed as:

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Mass Reduction Direct Manufacturing Cost (DMC) ($/lb) = 4.55 x Percentage of Mass
Reduction (2012$)
For example, this results in an estimated $80 (2012$) DMC increase for a 5 percent mass
reduction of a 7,000 pound vehicle and $318 (2012$) DMC increase for a 10 percent mass
reduction of a 7,000 pound vehicle, or $0,227 $/lb and $0.455/lb, respectively (both in 2012$).
Consistent with the 2017-2025 light-duty FRM, the agencies consider this DMC to be
applicable to MY2017 and consider mass reduction technology to be on the flat portion of the
learning curve in the 2017-2025MY timeframe. To estimate indirect costs for applied mass
reduction of up to 10 percent, the agencies have applied a low complexity ICM with near term
markups through 2018.
2.11.10.5 Electric Power Steering, HD Pickups and Vans
We have based the costs for electric power steering on the costs used in the light-duty
2017-2025 FRM but have scaled upward that cost by 50 percent to account for the larger HD
vehicles. Using that cost and converting to 2012$ results in a cost of $141 (DMC, 2012$, in
2015). We consider this technology to be on the flat portion of the learning curve (curve 8) and
have applied low complexity markups with near term markups through 2018. The resultant costs
for HD pickups and vans are shown in are shown below.
Table 2-275 Costs for Electric Power Steering
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Electric power steering (EPS)
DMC
$124
$121
$119
$117
$114
$113
$112
Electric power steering (EPS)
IC
$27
$27
$27
$27
$27
$27
$27
Electric power steering (EPS)
TC
$151
$148
$146
$144
$141
$140
$139
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.10.6 Low Drag Brakes, HD Pickups and Vans
We have based the costs for low drag brakes on the costs used in the light-duty 2017-
2025 FRM but have scaled upward that cost by 50 percent to account for the larger HD vehicles.
Using that cost and converting to 2012$ results in a cost of $91 (DMC, 2012$, in any year). We
consider this technology to be beyond the learning curve (curve 1) and have applied low
complexity markups with near term markups through 2018. The resultant costs for HD pickups
and vans are shown in are shown below.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-276 Costs for Low Drag Brakes
Gasoline & Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Low drag brakes
DMC
$91
$91
$91
$91
$91
$91
$91
Low drag brakes
IC
$18
$18
$18
$18
$18
$18
$18
Low drag brakes
TC
$109
$109
$109
$109
$109
$109
$109
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.11.10.7 Driveline Friction Reduction, Diesel HD Pickups & Vans
We have estimated the cost of driveline friction reduction based on the cost of secondary
axle disconnect in the light-duty 2017-2025 final rule. Using that cost of $80 (DMC, 2009$, in
2015), we have scaled upward by 50 percent to account for the larger HD componentry to arrive
at a cost of $126 (DMC, 2012$, in 2015). We consider this technology to be on the flat portion
of the learning curve (curve 3) and have applied low complexity markups with near term
markups through 2022. The resultant costs for driveline friction reduction (applied only to diesel
HD pickups & vans) are shown below.
Table 2-277 Costs for Driveline Friction Reduction
Diesel HD Pickups and Vans (2012$)
ITEM

2021
2022
2023
2024
2025
2026
2027
Driveline friction reduction
DMC
$108
$106
$104
$102
$100
$99
$98
Driveline friction reduction
IC
$30
$30
$24
$24
$24
$24
$24
Driveline friction reduction
TC
$139
$136
$128
$126
$124
$123
$122
Notes: DMC=direct manufacturing cost; IC=indirect cost; TC=total cost
2.12 Package Costs
Chapter 2.11 presents detailed technology costs along with penetration rates to illustrate
how each technology is accounted for in the package costs. Here we present package costs by
regulated sector (i.e., vocational heavy HD, urban vehicles) and package costs by MOVES
sourcetype (i.e., diesel refuse trucks). We determine package costs by MOVES sourcetype so
that we can calculate total program costs (i.e., package costs multiplied by vehicle sales) since
sourcetypes are the sales figures that we can glean from MOVES. As a result, the sourcetype
package costs presented here are the costs used in our program cost estimations.
2.12.1 Package Costs by Regulated Sector
2.12.1.1 Vocational Vehicles
We have estimated costs for 9 vocational segments and 2 fuels. We present package
costs in the tables below for these for alternative 3 relative to alternatives la and lb and
separately for diesel and gasoline vehicles.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-278 Package Costs for Regulated Vocational Segment
Alternative 3 Incremental to Alternative la & lb
Diesel (2013$)
WEIGHT CLASS
SPEED
2021
2022
2023
2024
2025
2026
2027
Light HD
Urban
$1,106
$1,083
$1,020
$1,959
$1,925
$1,873
$2,533
Light HD
Multipurpose
$1,164
$1,140
$1,079
$2,018
$1,983
$1,919
$2,571
Light HD
Regional
$873
$855
$825
$1,272
$1,251
$1,224
$1,486
Medium HD
Urban
$1,116
$1,092
$1,030
$2,082
$2,046
$1,977
$2,727
Medium HD
Multipurpose
$1,146
$1,123
$1,058
$2,110
$2,074
$2,004
$2,771
Medium HD
Regional
$851
$833
$800
$1,274
$1,252
$1,226
$1,500
Heavy HD
Urban
$1,334
$1,308
$1,236
$2,932
$2,882
$2,785
$4,151
Heavy HD
Multipurpose
$1,625
$1,595
$1,502
$3,813
$3,749
$3,638
$5,025
Heavy HD
Regional
$2,562
$2,517
$2,359
$4,009
$3,942
$3,869
$5,670
Table 2-279 Package Costs for Regulated Vocational Segment
Alternative 3 Incremental to Alternative la & lb
Gasoline (2013$)
WEIGHT CLASS
SPEED
2021
2022
2023
2024
2025
2026
2027
Light HD
Urban
$947
$930
$872
$1,649
$1,616
$1,569
$2,177
Light HD
Multipurpose
$1,004
$986
$931
$1,708
$1,673
$1,615
$2,215
Light HD
Regional
$714
$701
$677
$962
$941
$921
$1,130
Medium HD
Urban
$979
$961
$904
$1,805
$1,770
$1,705
$2,406
Medium HD
Multipurpose
$1,010
$991
$932
$1,833
$1,797
$1,732
$2,450
Medium HD
Regional
$715
$702
$674
$997
$975
$954
$1,179
Heavy HD
Urban
$1,198
$1,177
$1,110
$2,655
$2,606
$2,513
$3,830
Heavy HD
Multipurpose
$1,489
$1,464
$1,376
$3,536
$3,472
$3,366
$4,704
Heavy HD
Regional
$2,426
$2,386
$2,233
$3,732
$3,665
$3,598
$5,349
2.12.1.2 Tractors
We have estimated costs for 7 tractor segments and 1 fuel. We present package costs in
the tables below for these for alternative 3 relative to alternatives la and lb.
Table 2-280 Package Costs for Regulated Tractor Segment
Alternative 3 Incremental to Alternative la
Diesel (2013$)
CLASS
TYPE
2021
2022
2023
2024
2025
2026
2027
7
Day cab, low roof
$5,134
$5,052
$4,682
$8,037
$7,859
$7,728
$10,235
7
Day cab, high roof
$5,240
$5,151
$4,772
$8,210
$8,026
$7,852
$10,298
8
Day cab, low roof
$5,228
$5,143
$4,769
$8,201
$8,020
$7,887
$10,439
8
Day cab, high roof
$5,317
$5,227
$4,844
$8,358
$8,172
$7,993
$10,483
8
Sleeper cab, low roof
$7,181
$7,061
$6,580
$11,100
$10,871
$10,714
$13,535
8
Sleeper cab, mid roof
$7,175
$7,056
$6,574
$11,100
$10,871
$10,714
$13,574
8
Sleeper cab, high roof
$7,276
$7,239
$6,751
$11,306
$11,068
$10,857
$13,749

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-281 Package Costs for Regulated Tractor Segment
Alternative 3 Incremental to Alternative lb
Diesel (2013$)
CLASS
TYPE
2021
2022
2023
2024
2025
2026
2027
7
Day cab, low roof
$5,267
$5,112
$4,659
$7,944
$7,705
$7,536
$9,937
7
Day cab, high roof
$5,093
$4,977
$4,594
$8,016
$7,816
$7,621
$10,042
8
Day cab, low roof
$5,360
$5,203
$4,745
$8,108
$7,866
$7,695
$10,141
8
Day cab, high roof
$5,170
$5,053
$4,667
$8,164
$7,962
$7,763
$10,227
8
Sleeper cab, low roof
$7,195
$6,988
$6,438
$10,883
$10,614
$10,404
$13,140
8
Sleeper cab, mid roof
$7,102
$6,886
$6,337
$10,800
$10,514
$10,306
$13,043
8
Sleeper cab, high roof
$7,115
$7,057
$6,577
$11,122
$10,871
$10,656
$13,515
2.12.1.3 Trailers
We have estimated costs for seven trailer types (i.e. for each of the subcategories). The
dry and refrigerated vans have identical stringency and technology packages, so costs are
presented by length category only. The tire-based design standards for non-aero box vans are a
single category, but separate non-aero costs were considered for long vans and short vans,
because we assumed all short vans have a single axle, which results in fewer wheels and tires and
lower costs. We present package costs in the tables below for these for alternative 3 relative to
alternative la and lb.
Table 2-282 Costs for Trailers
Alternative 3 Incremental to Alternative la (2013$)
TYPE
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Long van, Full aero
$716
$688
$673
$1,081
$1,061
$1,030
$1,204
$1,184
$1,183
$1,370
Long van, Partial aero
$1,441
$1,383
$1,352
$1,337
$1,313
$1,274
$1,251
$1,229
$1,213
$1,196
Long van, No aero
$461
$448
$435
$438
$429
$413
$405
$398
$390
$382
Short van, Full aero
$339
$330
$322
$772
$757
$733
$1,171
$1,151
$1,144
$1,204
Short van, Partial aero
$514
$500
$487
$957
$940
$910
$894
$879
$867
$855
Short van, No aero
$231
$224
$218
$219
$215
$207
$202
$199
$195
$191
Non-box
$448
$436
$424
$412
$406
$390
$383
$377
$361
$354
Table 2-283 Costs for Trailers
Alternative 3 Incremental to Alternative lb (2013$)
TYPE
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Long van, Full aero
$716
$676
$650
$1,047
$1,016
$975
$1,139
$1,109
$1,098
$1,276
Long van, Partial aero
$1,441
$1,383
$1,352
$1,337
$1,313
$1,274
$1,251
$1,229
$1,213
$1,196
Long van, No aero
$461
$448
$435
$438
$429
$413
$405
$398
$390
$382
Short van, Full aero
$339
$330
$322
$772
$757
$733
$1,171
$1,151
$1,144
$1,204
Short van, Partial aero
$514
$500
$487
$957
$940
$910
$894
$879
$867
$855
Short van, No aero
$231
$224
$218
$219
$215
$207
$202
$199
$195
$191
Non-box
$448
$436
$424
$412
$406
$390
$383
$377
$361
$354

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
2.12.1.4 HD Pickups and Vans
The costs presented in the table below are CAFE model outputs used in analysis Method
B. We describe the CAFE model and how these costs were generated in Chapter 6 and 11 of this
RIA.
Table 2-284 Package Costs for HD Pickups and Vans (2013$)
ALTERNATIVE
BASELINE
CASE
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
3
la
$114
$105
$108
$524
$516
$804
$963
$1,180
$1,244
$1,364
3
lb
$113
$105
$102
$513
$505
$793
$952
$1,168
$1,233
$1,349
2.12.2 Package Costs by MOVES Sourcetype
The package costs by segment can then be used to calculate package costs by MOVES
sourcetype. To do this, we need the percentage of the MOVES sourcetype fleet comprised of
each regulated sector. Table 2-285 shows this breakout for the vocational sector and Table 2-286
shows it for tractors. Package costs for vocational vehicles make the conservative assumption of
full program compliance rather than compliance with the more flexible, less costly custom
chassis program.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-285 Fleet Mix by MOVES Sourcetype and Regulated Sector — Vocational"
ENGINE
FUEL
SPEED
INTERCITY
TRANSIT
SCHOOL
REFUSE
SINGLE
SINGLE
MOTOR



BUS
BUS
BUS
TRUCKS
UNIT
SHORT
HAUL
UNIT
LONG
HAUL
HOMES
Light HD
Gasoline
Urban
0%
27%
1%
0%
41%
0%
0%
Light HD
Gasoline
Multipurpose
0%
0%
0%
0%
33%
0%
0%
Light HD
Gasoline
Regional
0%
0%
0%
0%
7%
0%
54%
Medium HD
Gasoline
Urban
0%
10%
85%
0%
7%
0%
0%
Medium HD
Gasoline
Multipurpose
0%
0%
9%
0%
9%
0%
0%
Medium HD
Gasoline
Regional
0%
0%
0%
0%
3%
0%
41%
Heavy HD
Gasoline
Urban
0%
63%
4%
0%
0%
0%
0%
Heavy HD
Gasoline
Multipurpose
0%
0%
0%
0%
0%
0%
0%
Heavy HD
Gasoline
Regional
0%
0%
0%
0%
0%
0%
5%
Light HD
Diesel
Urban
0%
0%
1%
0%
21%
0%
0%
Light HD
Diesel
Multipurpose
0%
0%
0%
0%
17%
0%
0%
Light HD
Diesel
Regional
2%
0%
0%
0%
4%
25%
54%
Medium HD
Diesel
Urban
0%
0%
85%
2%
12%
0%
0%
Medium HD
Diesel
Multipurpose
0%
0%
9%
0%
17%
0%
0%
Medium HD
Diesel
Regional
15%
0%
0%
0%
5%
37%
41%
Heavy HD
Diesel
Urban
0%
100%
4%
88%
5%
0%
0%
Heavy HD
Diesel
Multipurpose
0%
0%
0%
10%
15%
0%
0%
Heavy HD
Diesel
Regional
83%
0%
0%
0%
5%
37%
5%
Heavy HD
CNG
Urban
0%
100%
0%
0%
0%
0%
0%
Heavy HD
CNG
Multipurpose
0%
0%
0%
0%
0%
0%
0%
Heavy HD
CNG
Regional
0%
0%
0%
0%
0%
0%
0%
Note:
a Columns add to 100% or 0% within each fuel type.
Table 2-286 Fleet Mix by MOVES Sourcetype and Regulated Sector - Tractors3
ENGINE
MOVES
CLASS
CLASS
CLASS
CLASS
CLASS 8
CLASS 8
CLASS 8

SOURCETYPE
7
7
8
8
SLEEPER
SLEEPER
SLEEPER


DAY
DAY
DAY
DAY
CAB
CAB
CAB


CAB
CAB
CAB
CAB
LOW
MID
HIGH


LOW
HIGH
LOW
HIGH
ROOF
ROOF
ROOF


ROOF
ROOF
ROOF
ROOF



Medium
HD
Combination
Short haul
11%
11%
0%
0%
0%
0%
0%
Heavy
HD
Combination
Short haul
0%
0%
39%
39%
0%
0%
0%
Heavy
HD
Combination
Long haul
0%
0%
0%
0%
5%
15%
80%
Note:
a Combination short haul adds to 100% and long haul to 100%.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Using the fleet mix information shown in Table 2-285 and Table 2-286, along with the
package costs shown in Chapter 2.12.1, we can generate the package costs by MOVES
sourcetype (note that package costs by MOVES sourcetype differ from package costs by
regulated sector only for vocational vehicles and tractors; trailer and HD pickup and van costs do
not change). These costs are shown below.
Table 2-287 Package Costs by MOVES Sourcetype
Alternative 3 Incremental to Alternative la (2013$)
SOURCETYPE
FUEL
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Intercity Bus
Diesel
$0
$0
$0
$2,266
$2,225
$2,089
$3,534
$3,475
$3,411
$4,946
Transit Bus
Diesel
$0
$0
$0
$1,334
$1,308
$1,236
$2,932
$2,882
$2,785
$4,151
School Bus
Diesel
$0
$0
$0
$1,130
$1,106
$1,043
$2,127
$2,090
$2,019
$2,799
Refuse Truck
Diesel
$0
$0
$0
$1,357
$1,330
$1,256
$2,996
$2,945
$2,847
$4,198
SingleUnit ShortHaul
Diesel
$0
$0
$0
$1,270
$1,244
$1,174
$2,392
$2,351
$2,281
$3,142
SingleUnit LongHaul
Diesel
$0
$0
$0
$1,497
$1,468
$1,389
$2,296
$2,258
$2,214
$3,056
MotorHome
Diesel
$0
$0
$0
$954
$934
$896
$1,418
$1,394
$1,365
$1,714
Intercity Bus
Gasoline










Transit Bus
Gasoline
$0
$0
$0
$1,109
$1,089
$1,026
$2,302
$2,258
$2,181
$3,247
School Bus
Gasoline
$0
$0
$0
$993
$975
$917
$1,850
$1,813
$1,747
$2,477
Refuse Truck
Gasoline










SingleUnit ShortHaul
Gasoline
$0
$0
$0
$951
$933
$880
$1,628
$1,595
$1,544
$2,126
SingleUnit LongHaul
Gasoline










MotorHome
Gasoline
$0
$0
$0
$805
$791
$758
$1,123
$1,100
$1,076
$1,374
Transit Bus
CNG
$0
$0
$0
$1,059
$1,039
$973
$2,519
$2,476
$2,384
$3,705
Comb ShortHaul
Tractor
Diesel
$0
$0
$0
$5,254
$5,167
$4,789
$8,245
$8,062
$7,907
$10,418
Comb LongHaul
Tractor
Diesel
$0
$0
$0
$7,256
$7,203
$6,716
$11,265
$11,029
$10,829
$13,712
Long Van, Full Aero

$716
$688
$673
$1,081
$1,061
$1,030
$1,204
$1,184
$1,183
$1,370
Long Van, Partial
Aero

$1,441
$1,383
$1,352
$1,337
$1,313
$1,274
$1,251
$1,229
$1,213
$1,196
Long Van, No Aero

$461
$448
$435
$438
$429
$413
$405
$398
$390
$382
Short Van, Full Aero

$339
$330
$322
$772
$757
$733
$1,171
$1,151
$1,144
$1,204
Short Van, Partial
Aero

$514
$500
$487
$957
$940
$910
$894
$879
$867
$855
Short Van, No Aero

$231
$224
$218
$219
$215
$207
$202
$199
$195
$191
Non-Box

$448
$436
$424
$412
$406
$390
$383
$377
$361
$354
Vocational
Weighted
Avg
$0
$0
$0
$1,110
$1,088
$1,027
$2,022
$1,986
$1,927
$2,662
Tractor/Trailer
Weighted
Avg
$568
$548
$535
$7,352
$7,269
$6,799
$11,134
$10,901
$10,712
$13,550
Note: Blank cells indicate no such vehicles of that sourcetype/fuel combination.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
Table 2-288 Package Costs by MOVES Sourcetype
Alternative 3 Incremental to Alternative lb (2013$)
SOURCETYPE
FUEL
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
Intercity Bus
Diesel
$0
$0
$0
$2,266
$2,225
$2,089
$3,534
$3,475
$3,411
$4,946
Transit Bus
Diesel
$0
$0
$0
$1,334
$1,308
$1,236
$2,932
$2,882
$2,785
$4,151
School Bus
Diesel
$0
$0
$0
$1,130
$1,106
$1,043
$2,127
$2,090
$2,019
$2,799
Refuse Truck
Diesel
$0
$0
$0
$1,357
$1,330
$1,256
$2,996
$2,945
$2,847
$4,198
SingleUnit
ShortHaul
Diesel
$0
$0
$0
$1,270
$1,244
$1,174
$2,392
$2,351
$2,281
$3,142
SingleUnit
LongHaul
Diesel
$0
$0
$0
$1,497
$1,468
$1,389
$2,296
$2,258
$2,214
$3,056
MotorHome
Diesel
$0
$0
$0
$954
$934
$896
$1,418
$1,394
$1,365
$1,714
Intercity Bus
Gasoline










Transit Bus
Gasoline
$0
$0
$0
$1,109
$1,089
$1,026
$2,302
$2,258
$2,181
$3,247
School Bus
Gasoline
$0
$0
$0
$993
$975
$917
$1,850
$1,813
$1,747
$2,477
Refuse Truck
Gasoline










SingleUnit
ShortHaul
Gasoline
$0
$0
$0
$951
$933
$880
$1,628
$1,595
$1,544
$2,126
SingleUnit
LongHaul
Gasoline










MotorHome
Gasoline
$0
$0
$0
$805
$791
$758
$1,123
$1,100
$1,076
$1,374
Transit Bus
CNG
$0
$0
$0
$1,059
$1,039
$973
$2,519
$2,476
$2,384
$3,705
Comb
ShortHaul
Diesel
$0
$0
$0
$5,246
$5,110
$4,689
$8,101
$7,880
$7,696
$10,141
Comb
LongHaul
Diesel
$0
$0
$0
$7,117
$7,028
$6,534
$11,061
$10,804
$10,591
$13,426
Long Van, Full
Aero

$716
$676
$650
$1,047
$1,016
$975
$1,139
$1,109
$1,098
$1,276
Long Van,
Partial Aero

$1,441
$1,383
$1,352
$1,337
$1,313
$1,274
$1,251
$1,229
$1,213
$1,196
Long Van, No
Aero

$461
$448
$435
$438
$429
$413
$405
$398
$390
$382
Short Van, Full
Aero

$339
$330
$322
$772
$757
$733
$1,171
$1,151
$1,144
$1,204
Short Van,
Partial Aero

$514
$500
$487
$957
$940
$910
$894
$879
$867
$855
Short Van, No
Aero

$231
$224
$218
$219
$215
$207
$202
$199
$195
$191
Non-Box

$448
$436
$424
$412
$406
$390
$383
$377
$361
$354
Vocational
Weighted
Avg
$0
$0
$0
$1,110
$1,088
$1,027
$2,022
$1,986
$1,927
$2,662
Tractor/Trailer
Weighted
Avg
$639
$548
$482
$7,248
$7,120
$6,624
$10,925
$10,660
$10,447
$13,226

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
References
1	Committee to Assess Fuel Economy Technologies for Medium- and Heavy-Duty Vehicles; National Research
Council; Transportation Research Board (2010). "Technologies and Approaches to Reducing the Fuel Consumption
of Medium- and Heavy-Duty Vehicles," (hereafter, "NAS Report"). Washington, D.C., The National Academies
Press. Available electronically from the National Academies Press Website at
http://www.nap.edu/catalog.php?record_id=12845 (last accessed September 10, 2010).
2	TIAX, LLC. "Assessment of Fuel Economy Technologies for Medium- and Heavy-Duty Vehicles," Final Report
to the National Academy of Sciences, November 19, 2009.
3	U.S. EPA. EPA Lumped Parameter Model HD Version 1.0.0.5, 2010. Docket #EPA-HQ-OAR-2010-0162.
4	NESCCAF, ICCT, Southwest Research Institute, and TIAX. Reducing Heavy-Duty Long Haul Combination
Truck Fuel Consumption and CO2 Emissions. October 2009.
5ICF International. Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy-Duty On-
Road Vehicles. July 2010. Docket Identification Number EPA-HQ-OAR-2010-0162-0044.
6	Reinhart, T.E. (2015, June). Commercial Medium- and Heavy-Duty Truck Fuel Efficiency Technology Study -
Report #1. (Report No. DOT HS 812 146). Washington, DC: National Highway Traffic Safety Administration.
7	Reinhart, T. (February 2016). Commercial Medium- and Heavy-Duty (MD/HD) Truck Fuel Efficiency
Technology Study - Report #2. Washington, DC: National Highway Traffic Safety Administration. EPA-HQ-OAR-
2014-0827-1623.
8	Schubert, R., Chan, M., Law, K. (2015). Commercial Medium- and Heavy-Duty Truck Fuel Efficiency
Technology Cost Study. Washington, DC: National Highway Traffic Safety Administration.
9	Northeast States Center for a Clean Air Future. "Reducing Greenhouse Gas Emissions from Light-Duty Motor
Vehicles." September 2004.
10	Energy and Environmental Analysis, Inc. "Technology to Improve the Fuel Economy of Light Duty Trucks to
2015." May 2006.
11	"Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 - 2014," EPA-
420-R-14-023, October 2014. Available at http://www3.epa.gov/otaq/fetrends.htm (last accessed October 31, 2014).
12	"Development and Optimization of the Ford 3.5L V6 EcoBoost Combustion System," Yi,J., Wooldridge, S.,
Coulson, G., Hilditch, J. Iyer, C.O., Moilanen, P., Papaioannou, G., Reiche, D. Shelby, M., VanDerWege, B.,
Weaver, C. Xu, Z., Davis, G., Hinds, B. Schamel, A. SAE Technical Paper No. 2009-01-1494, 2009, Docket EPA-
HQ-OAR-2009-0472-2860.
13	David Woldring and Tilo Landenfeld of Bosch, and Mark J. Christie of Ricardo, "DI Boost: Application of a
High Performance Gasoline Direct Injection Concept," SAE 2007-01-1410. Available at
http://www.sae.org/technical/papers/2007-01-1410 (last accessed Nov. 9, 2008).
14	Yves Boccadoro, Loi'c Kermanac'h, Laurent Siauve, and Jean-Michel Vincent, Renault Powertrain Division, "The
New Renault TCE 1.2L Turbocharged Gasoline Engine," 28th Vienna Motor Symposium, April 2007.
15	Tobias Heiter, Matthias Philipp, Robert Bosch, "Gasoline Direct Injection: Is There a Simplified, Cost-Optimal
System Approach for an Attractive Future of Gasoline Engines?" AVL Engine & Environment Conference,
September 2005.
16	Stanton, Donald. "Enabling High Efficiency Clean Combustion." 2009 Semi-Mega Merit Review of the
Department of Energy. May 21, 2009. Last accessed on August 25, 2010 at
http://wwwl.eere.energy.gOv/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_40_stanton.pdf.
17	Zhang, H. Heavy Truck Engine Development & HECC. 2009 DOE Semi-Mega Merit Review, May 21, 2009.
Last accessed on August 25, 2010 at
http://wwwl.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_42_zhang.pdf.
18	de Ojeda, W., SuperTruck - Development and Demonstration of a Fuel-Efficient Class 8 Tractor & Trailer Engine
Systems, http://energy.gov/eere/vehicles/downloads/supertruck-development-and-demonstration-fuel-efficient-class-
8-tractor-.\
19	Zhang, H. Detroit Diesel. "High Efficiency Clean Combustion for Heavy-Duty Engine." August 6, 2008
presentation to DEER Conference. Last accessed on August 25, 2010 at
http://wwwl.eere.energy.gov/vehiclesandfuels/pdfs/deer_2008/session5/deer08_zhang.pdf

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
20	Singh, S., SuperTruck Program: Engine Project Review Recovery Act - Class 8 Truck Freight Efficiency
Improvement Project, DOE SuperTruck Merit Review, Department of Energy, 2014.
21	See the NAS Report, page 53 cites Detroit Diesel Corporation, DD15 Brochure, DDC-EMC-BRO-0003-0408,
April 2008
22	Greszler, A., "View from the Bridge - Commercial Vehicle Perspective," DEER Conference, Department of
Energy, 2012. http://wwwl.eere.energy.gov/vehiclesandfuels/resources/proceedings/2012_deer_presentations.html.
23	de Ojeda, W., "Development and Demonstration of a Fuel-Efficient HD Engine (Department of Energy
SuperTruck Program)," DEER Conference, Department of Energy, 2012.
http://wwwl.eere.energy.gov/vehiclesandfuels/resources/proceedings/2012_deer_presentations.html,
24	Jadin, D., "SuperTruck - Development and Demonstration of a Fuel-Efficient Class 8 Tractor & Trailer," DOE
Supertruck Merit Review, Department of Energy, 2012.
http://wwwl.eere.energy.gov/vehiclesandfuels/resources/proceedings/2012_deer_presentations.html,
25	Koeberlein, D., Technology and System Level Demonstration of Highly Efficient and Clean, Diesel Powered
Class 8 Trucks, 2012, http://energy.gov/sites/prod/files/2014/03/fl0/ace057_koeberlein_2012_o.pdf
26	Sisken, K., Rotz, D., "Recovery Act - Class 8 Truck Freight Efficiency Improvement Project," DOE Supertruck
Merit Review, Department of Energy, 2012.
http://wwwl.eere.energy.gov/vehiclesandfuels/resources/proceedings/2012_deer_presentations.html.
27	de Ojeda, W., "Development and Demonstration of a Fuel-Efficient HD Truck," DEER Conference, Department
of Energy, 2011,
http://wwwl.eere.energy.gov/vehiclesandfuels/resources/proceedings/201 l_deer_presentations.html,
28	SAE Off-Highway Magazine. Federal-Mogul's Latest Piston Ring Developments help reduce friction in heavy-
duty engines. October 2, 2014. Last accessed on October 3, 2014 at
http://www.oemoffhighway.com/press_release/12007334/federal-moguls-latest-piston-ring-developments-help-
rcducc-friction-in-hcavY-duty-cngincs.
29	Sisken, K., SuperTruck Program: Engine Project Review Recovery Act - Class 8 Truck Freight Efficiency
Improvement Project, DOE Supertruck Merit Review, Department of Energy, 2013.
30	Amar, P., SuperTruck Development and Demonstration of a Fuel-Efficient Class 8 Highway Vehicle Systems,
DOE Supertruck Merit Review, Department of Energy, 2013.
31	Koeberlein, D., Technology and System Level Demonstration of Highly Efficient and Clean, Diesel Powered
Class 8 Trucks, DOE Supertruck Merit Review, Department of Energy, 2013.
32	Stanton, D. W., Systematic development of highly efficient and clean engines to meet future commercial vehicle
greenhouse gas regulations. Presented at SAE Commercial Vehicle Engineering Congress. Chicago, IL, October
2013.
33	Amar, P., Volvo SuperTruck Powertrain Technologies for Efficiency Improvement, DOE Supertruck Merit
Review, Department of Energy, 2014.
34	Rotz, D., Super Truck Program: Vehicle Project Review, DOE Supertruck Merit Review, Department of Energy,
2014.
35	Damon, K., DOE SuperTruck Program - Technology and System Level Demonstration of Highly Efficient b and
Clean, Diesel Powered Class 8 Trucks, DOE Supertruck Merit Review, Department of Energy, 2014.
36	2015 Annual Fleet Fuel Study, report of a study conducted by the North American Council for Freight Efficiency
(NACFE), May 6, 2015.
37	Assumes travel on level road at 65 MPH. (21st Century Truck Partnership Roadmap and Technical White Papers,
December 2006. U.S. Department of Energy, Energy Efficiency and Renewable Energy Program. 21CTP-003. p.
36.
38	Reducing Heavy-Duty Long Haul Combination Truck Fuel Consumption and CO2 Emissions, ICCT, October
2009.
39	Overdrive magazine September 2014, "Western Star introduces re-designed on-highway tractor,"
http://www.overdriveonline.com/photo-video-western-star-unveils-re-designed-on-highway-
tractor/?utm_medium=overdrive&utm_campaign=site_click&utm_source=top_stories
40	Cornelius Pfeifer (Rochling Automotive), Society of Automotive Engineer (SAE) Paper #2014-01-0633:
"Evolution of Active Grille Shutters." April 1, 2014.
41	Jason Leuschen and Kevin R. Cooper (National Research Council of Canada), Society of Automotive Engineer
(SAE) Paper #2006-01-3456: "Full-Scale Wind Tunnel Tests of Production and Prototype, Second-Generation
Aerodynamic Drag-Reducing Devices for Tractor-Trailers.," November 2, 2006.
42	http://www.todaystrucking.com/supertruck-flies-to-future-of-fuel-efficiency-at-107-mpg.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
43	"Tires & Truck Fuel Economy," A New Perspective. Bridgestone Firestone, North American Tire, LLC, Special
Edition Four, 2008.
44	"Michelin's Green Meters," Press Kit, October, 30, 2007. http://www.michelin-green-
meter.com/main.php?cLang=en (Complete Press File, Viewed March 6, 2010).
45	Argonne National Laboratory. "Evaluation of Fuel Consumption Potential of Medium and Heavy Duty Vehicles
through Modeling and Simulation." October 2009. Page 91.
46	21st Century Truck Partnership, "Roadmap and technical White Papers," U.S. Department of Energy, Technical
paper: 21CTP-0003, December 2006.
47	NACFE December 2010 "Executive Report - Wide Base Tires," available at http://nacfe.org/wp-
content/uploads/2010/12/NACFE-ER-1002-Wide-Base-Tires-Dec-2010.pdf.
48	"Energy Efficiency Strategies for Freight Trucking: Potential Impact on Fuel Use and Greenhouse Gas
Emissions," J. Ang-Olson, W. Schroer, Transportation Research Record: Journal of the Transportation Research
Board, 2002(1815): 11-18.
49	"Effect of Single Wide Tires and Trailer Aerodynamics on Fuel efficiency and NOx Emissions of Class 8 Line-
Haul Tractor-Trailer," J. Bachman, A. Erb, C. Bynum, U.S. Environmental Protection Agency, SAE International,
Paper Number 05CV-45, 2005.
50	"Class 8 Heavy Truck Duty Cycle Project Final Report," U.S. Department of Energy, Oak Ridge National
Laboratory, ORNL/TM-2008/122, p. 21, December 2008. Accessed January 19, 2010 at
http ://cta. ornl. gov/cta/Publications/Reports/ORNL_TM_2008-122.pdf.
51	"Are Ultra-Wide, Ultra-Low Aspect Ratio Tires the Next Big Thing?" K. Rohlwing, Today's Tire Industry, Vol.
I,	Issue 1, July/August, July 2003.
52	"New Generation Wide Base Single Tires," American Trucking Association, White paper presented at the
International Workshop on the use of wide tires sponsored by Federal Highway Administration, Turner-Fairbank
Highway Research Center, October 25-26, 2007, Revision 9, December 21, 2007, Accessed on February 3, 2010 at
http://www.arc.unr.edu/Workshops/Wide_Tires/Wide_Base_Summary-v9-ATA-whitepaper.pdf
53	HDT Trucking info, March 2014,"Switching to Wide-Base Singles: Keys to Success," Available online:
http://www.truckinginfo.eom/channel/equipment/article/story/2014/03/switching-to-wide-base-singles-keys-to-
success.asp.v
54	"Recommended Practice: Guidelines for Outset Wide Base Wheels for Drive, Trailer and Auxiliary Axle
Applications (Draft)," Technology and Maintenance Council, Council of American Trucking Associations,
circulated September 28, 2009.
55	"Tire Pressure Systems - Confidence Report." North American Council for Freight Efficiency. 2013. Available
online: http://nacfe.org/wp-content/uploads/2014/01/TPS-Detailed-Confidence-Reportl.pdf.
56	Technology and Maintenance Council of the American Trucking Associations, Tire Air Pressure Study, Tire
Debris Prevention Task Force S.2 Tire & Wheel Study Group; May 2002.
57	"Commercial Vehicle Tire Condition Sensors," Federal Motor Carrier Safety Administration. Report No.
FMCSA-PSV-04-002, November 2003.
58	U.S. Environmental Protection Agency Office of Transportation and Air Quality SmartWay Transport
Partnership, A Glance at Clean Freight Strategies: Automatic Tire Inflation Systems EPA 420-F-04-0010; February
2004.
59	"A Day in the Life of a Tire," Pressure Systems International, Presented to EPA on August 20, 2014.
60	"Buses & Retread Tires," The Tire Retread & Repair Information Bureau, Pacific Grove, Ca., Accessed on
January 27, 2010 at http://www.retread.org/packet/index.cfm/ID/284.htm.
61	"What are Retreaders Doing to Improve Fuel Efficiency?" H. Inman, Tire Review, December 11, 2006, Accessed
on February 18, 2010 at
http://www.tirereview.com/Article/59777/what_are_retreaders_doing_to_improve_fuel_efficiency.aspx.
62	Modern Tire Dealer, Top Retreaders, ibid.
63	Tire Industry Association and the Tire Retread and Repair Information Bureau, Understanding Retreading,
accessed August 2, 2010, at http://www.retread.org/pdf/UR/UnderstandingRetreading_web.pdf.
64	Todaystrucking.com, Retread Tires FAQ (07/17/2006), accessed August 2, 2010.
65	"Better Fuel Efficiency? Start with a Strong Tire Program," H. Inman, Fleet & Tire 2006, Tire Review, December
II,	2006, Accessed on February 18, 2010 at http://www.tirereview.com/better-fuel-economy-start-with-a-strong-
tire-program/.
66	See 2010 NAS Report, Note 1, Finding 4-6, page 87.
67	See NHTSA Technology Report #1 (2015), Note 6.
68	NACFE. Executive Report - 6x2 (Dead Axle) Tractors. November 2010. See Docket.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
69	Reinhart, T.E. (2015, June). Commercial Medium- and Heavy-Duty Truck Fuel Efficiency Technology Study -
Report #1. (Report No. DOT HS 812 146). Washington, DC: National Highway Traffic Safety Administration.
70	Fleet Owner, "Meritor Expects to offer new tandem axle in 2013," http://fleetowner.com/equipment/meritor-
expects-offer-new-tandem-axle-2013, December 2012.
71	DanaHolding Corporation Patents (8,523,738, 8,795,125, and 8,911,321).
72	See 4WD Axle Actuator Housing at 1A Auto, accessed November 2014 from http://www.laauto.com/4wd-axle-
actuator-housing/c/264.
73	DriveAluminum. The Aluminum Advantage in Commercial Vehicle Applications Webinar. 2009. Last accessed
on May 21, 2015 at
http://www.drivealuminum.org/research-resources/PDF/Webinars/2009/The-Aluminum-Advantage-Commercial-
Vehicle-Applications-Webinar-2009-Dec-Commercial-Vehicle-Webinar.pdf/view.
74	Committee on the Assessment of Technologies for Improving Light-Duty Vehicle Fuel Economy; National
Research Council, "Assessment of Fuel Economy Technologies for Light-Duty Vehicles," 2011. Available at
http://www.nap.edu/catalog.php?record_id=12924 (last accessed Jun 27, 2012).
75	Energy Savings through Increased Fuel Economy for Heavy Duty Trucks," Therese Langer,
American Council for an Energy-Efficient Economy prepared for the National Commission on Energy
Policy, February 11, 2004.
76	Best practices Guidebook for Greenhouse Gas Reductions in Freight Transportation," H.
Christopher Fey, Po-Yao Kuo, North Carolina State University prepared for the U.S. Department of
Transportation, October 4, 2007.
77U.S. EPA. http://www3.epa.gov/smartway/documents/weightreduction.pdf.
78	SAE World Congress, "Focus B-pillar 'tailor rolled' to 8 different thicknesses," Feb. 24, 2010. Available at
http://www.sae.org/mags/AEI/7695 (last accessed Jun. 10, 2012).
79	"Preliminary Vehicle Mass Estimation Using Empirical Subsystem Influence Coefficients," Malen, D.E., Reddy,
K. Auto-Steel Partnership Report, May 2007, Docket EPA-HQ-OAR-2009-0472-0169. Accessed on the Internet on
May 30, 2009 at: http://www.a-sp.org/database/custom/Mass%20Compounding%20-%20Final%20Report.pdf.
80	"Benefit Analysis: Use of Aluminum Structures in Conjunction with Alternative Powertrain Technologies in
Automobiles," Bull, M. Chavali, R., Mascarin, A., Aluminum Association Research Report, May 2008, Docket
EPA-HQ-OAR-2009-0472-0168. Accessed on the Internet on April 30, 2009 at:
http://www.autoaluminum.org/downloads/IBIS-Powertrain-Study.pdf.
81	American Trucking Association. Last viewed on January 29, 2010 at
http://www.trucksdeliver.org/recommendations/speed-limits.html.
82	U.S. EPA SmartWay Transport Partnership. Last viewed on January 28, 2010 at
http://www3.epa.gov/smartway/transport/documents/tech/reducedspeed.pdf.
83	Department for Transport, Vehicle and Operator Services Agency. Last viewed on January 6, 2010 at
http://www.dft.gov.uk/vosa/newsandevents/pressreleases/2006pressreleases/28-12-06speedlimiterlegislation. htnx
84	Transport Canada. Summary Report - Assessment of a Heavy Truck Speed Limiter Requirement in Canada. Last
viewed on January 6, 2010 at http://www.tc.gc.ca/eng/roadsafety/tp-tpl4808-menu-370.htnx
85	See TIAX 2009, Note 2, at page 4-98.
86	Gaines, L. and D. Santini. Argonne National Laboratory, Economic Analysis of Commercial Idling Reduction
Technologies.
87	Gaines, L. and D. Santini. Argonne National Laboratory, Economic Analysis of Commercial Idling Reduction
Technologies.
88ICF International. Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy-Duty On-
Road Vehicles. July 2010. Docket Identification Number EPA-HQ-OAR-2010-0162-0044.
89	National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium- and
Heavy-Duty Vehicles. March 2010. Page 124.
90	Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use by Idling Commercial Trucks. 2006. Page 6.
91	Brodrick, C., T.Lipman, M. Farshchi, H. Dwyer, S. Gouse III, D.B. Harris, and F.King, Jr. Potential Benefits of
Utilizing Fuel Cell Auxiliary Power Units in Lieu of Heavy-Duty Truck Engine Idling. 2001. Page 3.
92	Lim, Han. Study of Exhaust Emissions from Idling Heavy-Duty Diesel Trucks and Commercially Available Idle-
Reducing Devices. EPA420-R-02-052. 2002. Page 2.
93	Kahn, ABM, N. Clark, G. Thompson, W.S. Wayne, M. Gautam, and D. Lyons. Idle Emissions from Heavy-Duty
Diesel Vehicles: Review and Recent Data. 2006. Journal of Air and Waste Management Association. Page 1405.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
94NACFE, June 2014. Confidence Report: Idle-Reduction Solutions. Available at
http://www.carbonwarroom.com/sites/default/files/reports/Idle-Reduction_Confidence_Report.pdf (accessed
November 2014).
95	See Vanner battery-inverter Systems at http://www.vanner.com/.
96	See eNow solar systems, http://www.enowenergy.com/.
97	Schwarz, W., Harnisch, J. 2003. "Establishing Leakage Rates of Mobile Air Conditioners." Prepared for the
European Commission (DG Environment), Doc B4-3040/2002/337136/MAR/C1.
98	Vincent, R., Cleary, K., Ayala, A., Corey, R. 2004. "Emissions of HFC-134a from Light-Duty Vehicles in
California." SAE 2004-01-2256.
99	Society of Automotive Engineers, "IMAC Team 1 - Refrigerant Leakage Reduction, Final Report to Sponsors,"
2006.
100	California Air Resources Board. Letter from Michael Carter to Matthew Spears dated December 3, 2014. Solar
Control: Heavy-Duty Vehicles White Paper. Docket EPA-HA-OAR-2014-0827.
101	National Renewal Energy Laboratory. Reducing Long-Haul Truck Idle Loads and Resulting Fuel Use.
Presented by Jason A. Lustbader to EPA on July 29, 2014. See Docket EPA-HA-OAR-2014-0827.
102	See NHTSA Technology Report #1 (2015), Note 6.
103	U.S. EPA and NHTSA, "Final Rulemaking to Establish Light-Duty Vehicle Greenhouse Gas Emission Standards
and Corporate Average Fuel Economy Standards - Joint Technical Support Document," 2010. Last viewed on June
3, 2010 at http://www3.epa.gov/otaq/climate/regulations/420rl0901.pdf.
104	"Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends: 1975 - 2014,"
EPA-420-R-14-023, October 2014. Available at http://www3.epa.gov/otaq/fetrends.htm (last accessed October 31,
2014).
105	"Development and Optimization of the Ford 3.5L V6 EcoBoost Combustion System," Yi, J., Wooldridge, S.,
Coulson, G., Hilditch, J. Iyer, C.O., Moilanen, P., Papaioannou, G., Reiche, D. Shelby, M., VanDerWege, B.,
Weaver, C. Xu, Z., Davis, G., Hinds, B. Schamel, A. SAE Technical Paper No. 2009-01-1494, 2009, Docket EPA-
HQ-OAR-2009-0472-2860.
106	David Woldring and Tilo Landenfeld of Bosch, and Mark J. Christie of Ricardo, "DI Boost: Application of a
High Performance Gasoline Direct Injection Concept," SAE 2007-01-1410. Available at
http://www.sae.org/technical/papers/2007-01-1410 (last accessed Nov. 9, 2008).
107	Yves Boccadoro, Loi'c Kermanac'h, Laurent Siauve, and Jean-Michel Vincent, Renault Powertrain Division,
"The New Renault TCE 1.2L Turbocharged Gasoline Engine," 28th Vienna Motor Symposium, April 2007.
108	Tobias Heiter, Matthias Philipp, Robert Bosch, "Gasoline Direct Injection: Is There a Simplified, Cost-Optimal
System Approach for an Attractive Future of Gasoline Engines?" AVL Engine & Environment Conference,
September 2005.
109	U.S. EPA and NHTSA, "Final Rulemaking to Establish Light-Duty Vehicle Greenhouse Gas Emission Standards
and Corporate Average Fuel Economy Standards - Joint Technical Support Document," 2010. Last viewed on June
3, 2010 at http://www3.epa.gOv/otaq/climate/regulations/420rl0901.pdf.
no "All-new-Ford-engineered, Ford-tested, Ford-built diesel maximizes 2011 Super Duty productivity," Ford press
release, August 3, 2010. Available at: http://www.media.ford.com (last accessed June 27, 2011).
111	Stanton, Donald. "Enabling High Efficiency Clean Combustion." 2009 Semi-Mega Merit Review of the
Department of Energy. May 21, 2009. Last accessed on August 25, 2010 at
http://wwwl.eere.energy.gOv/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_40_stanton.pdf.
112	Committee on the Assessment of Technologies for Improving Light-Duty Vehicle Fuel Economy; National
Research Council, "Assessment of Fuel Economy Technologies for Light-Duty Vehicles," 2011. Available at
http://www.nap.edu/catalog.php?record_id=12924 (last accessed Jun 27, 2012).
113	SAE World Congress, "Focus B-pillar 'tailor rolled' to 8 different thicknesses," Feb. 24, 2010. Available at
http://www.sae.org/mags/AEI/7695 (last accessed Jun. 10, 2012).
114	http://www.techtimes.com/articles/87961/20150925/ford-s-2017-f-25Q-super-dutv-with-an-aluminum-bodv-is-
the-toughest-smartest-and-most-capable-super-dutv-ever.htm. September 25, 2015.
115	https ://www.ford.com/trucks/superduty/2017/.
116	"2008/9 Blueprint for Sustainability," Ford Motor Company. Available at: http://
www.ford.com/go/sustainability (last accessed February 8, 2010).
117	"2015 North American Light Vehicle Aluminum Content Study - Executive Summary," June 2014,
http://www.drivealuminum.org/research-resources/PDF/Research/2014/2014-ducker-report (last accessed February
26, 2015).

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
118	http://www.foxnews.eom/leisure/2014/09/30/ford-confirms-increased-aluminum-use-on-next-gen-super-duty-
pickups/.
119	See EPA's heavy-duty engine certification database at http://www3.epa.gOv/otaq/certdata.htm#largeng.
120	See Phase 1 Federal Register at 76 FR 57231.
121	H. Zhang, J, Sanchez, M, Spears, "Alternative Heavy-duty Engine Test Procedure for Full Vehicle Certification,".
SAE Int. J. Commer. Veh. 8(2): 2015, doi: 10.4271/2015-01-2768,
122	EPA Docket Memo, Fleet Average Fuel Maps Projected for HD Phase 2 Vehicles, July 2016.
123	Cummins, 'Cummins visit on Phase 2 Engine standard," Greenhouse Gas Emissions Standards and Fuel
Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles - Phase 2 - Docket EPA-HQ-OAR-2014-
0827.
124	NACFE. Confidence Report: Programmable Engine Parameters. February 2015. Page 23.
125	Ostrander, Robert, et.al. (Meritor). Understanding the Effects of Engine Downspeeding on Drivetrain
Components. 2014. Page 2.
126	NACFE. Confidence Report for Idle Reduction Technologies.
127	Southwest Research Institute. Aerodynamic Test Report. July 2016. Docket EPA-HQ-OAR-2014-0827.
128	"Aerodynamic data from EPA's wind tunnel tests performed at Auto Research Center," Supplemental
Aerodynamic Data from EPA Testing. Available in the docket to this rulemaking: EPA-HQ-OAR-2014- 0827-
1624.
129	Delgado, Oscar. N. Lutsey. Advanced Tractor-Trailer Efficiency Technology Potential in the 2020-2030
Timeframe. April 2015. Docket EPA-HQ-OAR-2014-0827.
130	Delgado, Oscar. N. Lutsey. Advanced Tractor-Trailer Efficiency Technology Potential in the 2020-2030
Timeframe. April 2015. Docket EPA-HQ-OAR-2014-0827.
131	U.S. EPA. Memo to Docket. Coefficient of Rolling Resistance and Coefficient of Drag Certification Data for
Tractors. See Docket EPA-HQ-OAR-2014-0827.
132	Delgado, Oscar. N. Lutsey. Advanced Tractor-Trailer Efficiency Technology Potential in the 2020-2030
Timeframe. April 2015. Docket EPA-HQ-OAR-2014-0827.
133	North American Council for Freight Efficiency. Confidence Report: Electronically Controlled Transmissions.
December 2014.
134	Oak Ridge National Laboratory. "Powertrain Test Procedure Development for EPA GHG Certification of
Medium- and Heavy-Duty Engines and Vehicles." July 2016. Docket # EPA-HQ-OAR-2014-0827.
135	Stoltz, T and Dorobantu, M. Transmission Potential to Contribute to CO2 Reduction: 2020 and Beyond Line Haul
Perspective. ACEEE/ICCT Workshop on Emerging Technologies for Heavy-Duty Fuel Efficiency. July 2014.
136	U.S. EPA. Memorandum to the Docket. "Effectiveness of Technology to Increase Transmission Efficiency."
July 2016. EPA-HQ-OAR-2014-0827.
137	Ibid.
138	See the 2010 NAS Report, Note 1, page 67.
139	U.S. EPA. Memorandum to the Docket. "Effectiveness of Technology to Increase Axle Efficiency." July 2016.
EPA Docket # EPA-HQ-OAR-2014-0827.
140	Delgado, Oscar. N. Lutsey. "Advanced Tractor-Trailer Efficiency Technology Potential in the 2020-2030
Timeframe." April 2015. EPA Docket EPA-HQ-OAR-2014.0827.
141	U.S. Department of Energy. Transportation Energy Data Book, Edition 28-2009. Table 5.7.
142	U.S. EPA. Memo to Docket. Coefficient of Rolling Resistance and Coefficient of Drag Certification Data for
Tractors. See Docket EPA-HQ-OAR-2014-0827.
143	Memo to Docket. Coefficient of Rolling Resistance and Coefficient of Drag Certification Data for Tractors.
Docket EPA-HQ-OAR-2014-0827.
144	North American Council for Freight Efficiency. Confidence Report: Idle- Reduction Solutions. 2014. Page 13.
145	EPA Docket Memo, Fleet Average Fuel Maps Projected for HD Phase 2 Vehicles, July 2016.
146	Michael Ross, Validation Testing for Phase 2 Greenhouse Gas Test Procedures and the Greenhouse Gas
Emission Model (GEM) for Medium and Heavy-Duty Engines and Powertrains, Final Report to EPA, Southwest
Research Institute, found in docket of this rulemaking, EPA-HQ-OAR-2014-0827, June, 2016.
147	Joint Technical Support Document: Final Rulemaking for 2017-2025 Light-Duty Vehicle Greenhouse Gas
Emission Standards and Corporate Average Fuel Economy Standards, August 2012, available at
http://www3 .epa.gov/otaq/climate/documents/420rl2901 .pdf.
148	National Renewable Energy Laboratory July 2016, "The Development of Vocational Vehicle Drive Cycles and
Segmentation," NREL/TP-5400-65921.
149	See memorandum dated July 2016 titled, "Summary of Comments on Vocational Vehicle Baselines."

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
150	See Cummins-Eaton partnership at http://smartadvantagepowertrain.com/.
151	See TIAX 2009, Note 2, Table 4-48.
152	See http://www.truckinginfo.eom/channel/equipment/article/story/2014/10/2015-medium-duty-trucks-the-
vehicles-and-trends-to-look-for/page/3.aspx (downloaded November 2014).
153	For example, see XL Hybrids at http://www.xlhybrids.com/content/assets/Uploads/XL-BoxTruck-US-FLY-
8.5x11-0519-LR.pdf, and Crosspoint Kinetics at http://crosspointkinetics.com/members/kinetics-hybrid-partners
154	See spreadsheet file titled, "HD GHG Simple Hybrid Model v7.xlsx".
155	Green Fleet Magazine, The Latest Developments in EV Battery Technology, November 2013, available at
http://www.greenfleetmagazine.eom/article/story/2013/12/the-latest-developments-in-ev-battery-technology-
grn/page/l.aspx.
156	See memorandum on axle efficiency improvements, Note 139.
157	See Argonne National Laboratory 2009 report, page 91.
158	See memorandum dated May 2016 on Vocational Vehicle Tire Rolling Resistance Certification Data.
159	See NREL data at http://www.nrel.gov/vehiclesandfuels/fleettest/research_fleet_dna.htmL
160	See spreadsheet file titled, "Vocational-Standards GEMpostprocess.xlsx
161	See Cummins maintenance schedule, available at
http://www.cumminsbridgeway.com/pdf/parts/Recommended_Maintenance_Schedule.pdf (accessed March 2016).
162	NTEA, 2015 Work Truck Electrification and Idle Management Study.
163	See TIAX 2009, Note 2.
164	Morton, C. and Spargo, C.M., IET Electrical Systems in Transportation, Electrified hydraulic power steering
system in hybrid electric heavy trucks, Sept 2014, accessed June 2016 from
https://www.researchgate.net/publication/264983979_Electrified_hydraulic_power_steering_system_in_hybrid_elec
tricheavytrucks.
165	TIAX 2009, Note 2 pp. 3-5.
166	The Minnesota refrigerant leakage data can be found at
http://www.pca. state.mn.us/climatechange/mobileair.html#leakdata.
167	See Phase 1 RIA, Chapter 2.7.
168	Society of Automotive Engineers, "IMAC Team 1 - Refrigerant Leakage Reduction, Final Report to Sponsors,"
2006.
169	Society of Automotive Engineers Surface Vehicle Standard J2727, issued August 2008,
http://www.sae.org.
170	See Attachment 1 of public comments from CARB, "Aerodynamic Drag Reduction Technologies Testing for
Heavy- Duty Vocational Vehicles— Preliminary Results, July 2015, NREL/TP-5400-64610.
171	National Renewable Energy Laboratory July 2016, "Characterization of PTO and Idle Behavior for Utility
Vehicles" NREL/TP-5400-66747.
172	See http://westcoastcollaborative.Org/files/sector-fleets/WCC-LA-BEVBusinessCase2011-08-15 .pdf
173	Silver, Fred, and Brotherton, Tom. (CalHEAT) Research and Market Transformation Roadmap to 2020 for
Medium- and Heavy-Duty Trucks. California Energy Commission, June 2013.
174	Gallo, Jean-Baptiste, and Jasna Tomic (CalHEAT). 2013. Battery Electric Parcel Delivery Truck Testing and
Demonstration. California Energy Commission.
175	See memorandum titled, Vocational Vehicle Tire Rolling Resistance Certification Data.
176	American Public Transportation Association, "An Analysis of Transit Bus Axle Weight Issues", November 2014.
177	See spreadsheet file dated July 2016 titled, "FRM_Vocational-Standards_GEMpostprocess.xls.
178	Final Rulemaking to Establish Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium-
and Heavy-Duty Engines and Vehicles: Regulatory Impact Analysis, Environmental Protection Agency, Page 3-42.
Available at: https://www3 .epa.gov/otaq/climate/documents/420rl 1901 .pdf.
179	"Improving the Aerodynamic Efficiency of Heavy-Duty Vehicles - Wind Tunnel Test Results of Trailer-Based
Drag Reduction Technologies," McAuliffe, Brian R., National Research Council Canada, Report #: LTR-AL-2015-
0272. Available online: https://www.tc.gc.ca/eng/programs/environment-etv-menu-eng-2980.html.
180	"Aerodynamic data from EPA's wind tunnel tests performed at Auto Research Center," Supplemental
Aerodynamic Data from EPA Testing. Available in the docket to this rulemaking: EPA-HQ-OAR-2014- 0827-
1624.
181	"Aerodynamic data from EPA's wind tunnel tests performed at Auto Research Center," Supplemental
Aerodynamic Data from EPA Testing. Available in the docket to this rulemaking: EPA-HQ-OAR-2014- 0827-
1624.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
182	"Tires & Truck Fuel Economy: A New Perspective," The Tire Topic Magazine, Special Edition Four, 2008,
Bridgestone Firestone, North American Tire, LLC. Available online:
http://www.trucktires.com/bridgestone/us_eng/brochures/pdf/08-Tires_and_Truck_Fuel_Economy.pdf.
183	Truck Trailer Manufacturers Association letter to EPA. October 16, 2014. Docket EPA-HQ-OAR-2014-0827.
184	"T^e pressure Systems - Confidence Report." North American Council for Freight Efficiency. 2013. Available
online: http://nacfe.org/wp-content/uploads/2014/01/TPS-Detailed-Confidence-Reportl.pdf.
185	"A Day in the Life of a Tire," Pressure Systems International, Presented to EPA on August 20, 2014.
186	Federal Motor Carriers Safety Administration, "Commercial Vehicle Tire Condition Sensors," conducted by
Booz-Allen-Hamilton, Inc. November, 2003.
187	TMC Technology & Maintenance Council, "TMC Tire Air Pressure Study," May 2002.
188	FMCSA "Advanced Sensors and Applications: Commercial Motor Vehicle Tire Pressure Monitoring and
Maintenance," February 2014.
189	"Underinflated Commercial Low Rolling Resistance Truck Tires & It's Impact on Fuel Economy," October
2010. Pressure Systems International, Presentation Material shared with EPA on May 21, 2014.
190	Scarcelli, Jamie. "Fuel Efficiency for Trailers" Presented at ACEEE/ICCT Workshop: Emerging Technologies
for Heavy-Duty Vehicle Fuel Efficiency, Wabash National Corporation. July 22, 2014.
191	"Weight Reduction: A Glance at Clean Freight Strategies," EPA SmartWay. EPA420F09-043. Available at:
http://permanent.access.gpo.gov/gpo38937/EPA420F09-043.pdf.
192	Memo to docket regarding confidential weight reduction information obtained during SBREFA Panel, June 4,
2015.
193	Randall Scheps, Aluminum Association, "The Aluminum Advantage: Exploring Commercial Vehicles
Applications," presented in Ann Arbor, Michigan, June 18, 2009.
194ICF International. Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy-Duty
On-Road Vehicles. July 2010. See also, TIAX, LLC. "Assessment of Fuel Economy Technologies forMedium-
and Heavy-Duty Vehicles," Final Report to the National Academy of Sciences, November 19, 2009.
195	Schubert, R., Chan, M., Law, K. (2015). Commercial Medium- and Heavy-Duty (MD/HD) Truck Fuel Efficiency
Cost Study. Washington, DC: National Highway Traffic Safety Administration, Tetra Tech Technology Cost Report
(2015).
196	Schubert, R., Chan, M., Law, K. (2015). Commercial Medium- and Heavy-Duty Truck Fuel Efficiency
Technology Cost Study. Washington, DC: National Highway Traffic Safety Administration.
197	A. Rogozhin et al., Int. J. Production Economics 124 (2010) 360-368.
198	RTI International. Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers. July 2010.
199	Rogozhin, A., et al., "Using indirect cost multipliers to estimate the total cost of adding new technology in the
automobile industry," International Journal of Production Economics (2009), doi:10.1016/j.ijpe.2009.11.031.
200	Helfand, Gloria, and Todd Sherwood, "Documentation of the Development of Indirect Cost Multipliers for Three
Automotive Technologies," August 2009.
201	RTI International. Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers. July 2010.
202	See "Learning Curves in Manufacturing," L. Argote and D. Epple, Science, Volume 247; "Toward Cost Buy
down Via Learning-by-Doing for Environmental Energy Technologies, R. Williams, Princeton University,
Workshop on Learning-by-Doing in Energy Technologies, June 2003; "Industry Learning Environmental and the
Heterogeneity of Firm Performance, N. Balasubramanian and M. Lieberman, UCLA Anderson School of
Management, December 2006, Discussion Papers, Center for Economic Studies, Washington DC.
203	See "Learning Curves in Manufacturing," L. Argote and D. Epple, Science, Volume 247; "Toward Cost Buy
down Via Learning-by-Doing for Environmental Energy Technologies, R. Williams, Princeton University,
Workshop on Learning-by-Doing in Energy Technologies, June 2003; "Industry Learning Environments and the
Heterogeneity of Firm Performance, N. Balasubramanian and M. Lieberman, UCLA Anderson School of
Management, December 2006, Discussion Papers, Center for Economic Studies, Washington DC.
204	U.S. Energy Information Administration, Annual Energy Outlook 2014, Early Release; Report Number
DOE/EIA-0383ER (2014), December 16, 2013.
205	Bureau of Economic Analysis, Table 1.1.9 Implicit Price Deflators for Gross Domestic Product; as revised on
March 27, 2014.
206	Reducing Heavy-Duty Long Haul Combination Truck Fuel Consumption and CO2 Emissions; prepared by
Northeast States Center for a Clean Air Future (NESCCAF), International Council on Clean Transportation (ICCT),
Southwest Research Institute, TIAX, LLC; Final Report October 2009.
207	Comments to the docket from Allison Transmission, at I.D.2.a, page 6.
208	Comments to the docket from Allison Transmission, at I.D.2.a, page 6.

-------
*** E.O. 12866 Review — Revised — Do Not Cite, Quote, or Release During Review ***
209	Ryder website at http://www.ryderfleetproducts.com/tpms-accessories-c-l 1434; a PDF version of the site has
been placed in the docket.
210	Ben Sharpe (ICCT) and Mike Roeth (North American Council for Freight Efficiency), "Costs and Adoption
Rates of Fuel-Saving Technologies for Trailer in the North American On-Road Freight Sector," Feb 2014.

-------
Chapter 3: Test Procedures
Test procedures are a crucial aspect of the heavy-duty vehicle GHG and fuel
consumption program. This rulemaking establishes several new test procedures to be used as
part of compliance process for both engine and vehicle compliance. Specifically, these test
procedures are used to generate inputs to GEM. This chapter will describe the development
process for the test procedures, including the assessment of engines, aerodynamics, rolling
resistance, chassis dynamometer testing, powertrain testing, and duty cycles. The final
subsection of this chapter (3.10) describes the chassis test procedure used to verify compliance
with the standards for heavy duty pickups and vans.
This section focuses on the actual measurements procedures and generally does not
address how manufacturers will use this data to certify their engines and vehicles. For example,
Chapter 3.2 below discusses how to measure aerodynamic drag, but does not detail how
manufacturers will use the data to develop GEM aerodynamic inputs for certification.
3.1 Heavy-Duty Engine Test Procedure
The agencies are controlling heavy-duty engine fuel consumption and greenhouse gas
emissions through the use of engine certification. The program will mirror existing engine
regulations for the control of both GHG and non-GHG pollutants in many aspects. The
following sections provide an overview of the test procedures.
3.1.1 Existing Regulation Reference
Heavy-duty engines currently are certified for GHG and non-GHG pollutants using test
procedures developed by EPA. The Heavy-Duty Federal Test Procedure (FTP) is a transient test
consisting of second-by-second sequences of engine speed and torque pairs with values given in
normalized percent of maximum form. The cycle was computer generated from a dataset of 88
heavy-duty trucks in urban operation in New York and Los Angeles. These procedures are well-
defined, mirror in-use operating parameters, and thus we believe appropriate also for the
assessment of GHG emissions from heavy duty engines. Further, EPA is concerned that we
maintain a regulatory relationship between the non-GHG emissions and GHG emissions,
especially for control of CO2 and NOx. Therefore, the agencies will continue using the same
criteria pollutant test procedures for both the CO2 and fuel consumption standards.
For 2007 and later Heavy-Duty engines, 40 CFR parts 86 - "Control of Emissions from
New and In-Use Highway Vehicles and Engines" and 1065 - "Engine Testing Procedures" detail
the certification process. 40 CFR 86.007-11 defines the standard settings of Oxides of Nitrogen,
Non-Methane Hydrocarbons, Carbon Monoxide, and Particulate Matter. The duty cycles are
defined in 40 CFR part 86. The Federal Test Procedure engine test cycle is defined in 40 CFR
part 86 Appendix I. The Supplemental Emissions Test engine cycle is defined in 40 CFR
86.1360(b). All emission measurements and calculations are defined in 40 CFR part 1065, with
exceptions as noted in 40 CFR 86.007-11. The data requirements are defined in 40 CFR 86.001-
23 and 40 CFR 1065.695.

-------
The measurement method for CO2 is described in 40 CFR 1065.250. For measurement
of CH4 refer to 40 CFR 1065.260. For measurement of N2O refer to 40 CFR 1065.275. We
recommend that you use an analyzer that meets performance specifications shown in Table 1 of
40 CFR 1065.205. Note that your system must meet the linearity verification of 40 CFR
1065.307. To calculate the brake specific mass emissions for CO2, CH4 and N2O refer to 40
CFR 1065.650.
3.1.2 Engine Dynamometer Test Procedure Modifications
3.1.2.1	Fuel Consumption Calculation
EPA and NHTSA will calculate fuel consumption, as defined as gallons per brake
horsepower-hour, from the CO2 measurement, just as in the Phase 1 rule. The agencies are
continuing to use 8,887 grams of CO2 per gallon of gasoline and 10,180 g CO2 per gallon of
diesel fuel.
3.1.2.2	Regeneration Impact on Fuel Consumption and CO2 Emissions
The current engine test procedures also require the development of regeneration emission
rate and frequency factors to account for the emission changes during a regeneration event.1 In
Phase 1, the agencies adopted provisions to exclude CO2 emissions and fuel consumption due to
regeneration. However, for Phase 2, we will include CO2 emissions and fuel consumption due to
regeneration over the FTP and RMC cycles as determined using the infrequently regenerating
aftertreatment devices (IRAF) provisions in 40 CFR 1065.680. However, we are not finalizing
the inclusion of fuel consumption due to regeneration in the creation of the steady-state and cycle
average fuel maps used in GEM for vehicle compliance. Our assessment of the current non-
GHG regulatory program indicates that engine manufacturers have significantly reduced the
frequency of regeneration events. In addition, market forces already exist which create
incentives to reduce fuel consumption during regeneration.
3.1.2.3	Fuel Heating Value Correction
In the Phase 1 rule, the agencies collected baseline CO2 performance of diesel engines
from testing which used fuels with similar properties. The agencies will continue using a fuel-
specific correction factor for the fuel's energy content. This maintains consistency between test
labs, as well as prevents potential fuel changes that could occur in the future from changing the
effective stringency of the Phase 2 standards. The agencies found the average energy content of
the diesel fuel used at EPA's National Vehicle Fuel and Emissions Laboratory was 21,200 BTU
per pound of carbon. This value was determined by dividing the Net Heating Value (BTU per
pound) by the carbon weight fraction of the fuel used in testing. We will continue using the
Phase 1 corrections for diesel fuel, gasoline, natural gas, and liquid petroleum gas in 40 CFR
1036.530. We will also expand the table by adding dimethyl ether.
In addition to the fuel heating value correction, we are finalizing the addition of reference
carbon mass fraction values for these fuels to the Table 1 of 40 CFR 1036.530. These reference
values are used in the powertrain calculations 40 CFR 1037.550, steady-state engine fuel
mapping and fuel consumption at idle in 40 CFR 1036.535, and cycle average engine fuel

-------
mapping in 40 CFR 1036.540 to account for the difference in carbon mass fraction between the
test fuel and the reference fuel prior to correcting for the test fuel's mass-specific net energy
content.
The agencies are not finalizing fuel corrections for alcohols because the fuel chemistry is
homogeneous.
3.1.2.4	Urea Derived CO2 Correction
The agencies will allow manufacturers to correct compression ignition engine and
powertrain CO2 emission results (for engines utilizing urea SCR for NOx control) to account for
the contribution of urea derived CO2 emissions to the total engine CO2 emissions.
Urea derived CO2 can account for up to 1 percent of the total CO2 emissions. Urea is
produced from gaseous NH3 and gaseous CO2 that is captured from the atmosphere, thus CO2
derived from urea decomposition in diesel SCR emission control systems results in a net
emission of zero CO2 to the environment. In our test procedures for Phase 2, we allow
manufacturers to determine CO2 emissions either by measuring the CO2 emitted from the engine
or to determine it by measuring fuel flow rate during the test. If we do not allow for correction
of the urea derived CO2 emissions, this will result in a positive CO2 bias for CO2 emissions
determined by measuring the CO2 emitted from the engine. To perform this correction, we are
allowing you to determine the mass rate of urea injected over the duty cycle from the engine's
J1939 CAN signal or you may measure urea flow rate independently using good engineering
judgment. This value is used as an input to an equation that allows you to determine the mass
rate of CO2 from urea during the duty cycle. This resulting CO2 mass emission rate value is then
used as an input to the steady-state engine fuel map and engine fuel consumption at idle fuel
mass flow rate calculation in 40 CFR 1036.535, the cycle average engine fuel map calculation in
40 CFR 1036.540, and the total mass of CO2 emissions over the duty cycle calculations in 40
CFR 1037.550. Note that this correction is only allowed for CO2 measured from the engine and
not CO2 derived from fuel flow measurement.
The calculation for determination of the mass rate of CO2 from urea requires the user to
input the urea solution urea percent by mass. This calculation uses prescribed molecular weights
for CO2 and urea as given in 40 CFR 1065.1005 of 44.0095 and 60.05526 respectively. A 1:1
molar ratio of urea reactant to CO2 product is assumed.
To facilitate the ability of the agencies to make this correction, we are requiring that the
urea mass flow rate be broadcasted on the non-proprietary J1939 PGN (Parameter Group
Number) 61475 (and 61478 if applicable).
3.1.2.5	Multiple Fuel Maps
Engine manufacturers are being required to certify fuel maps to enable vehicle
manufacturers to run GEM for each vehicle configuration. However, modern heavy-duty
engines often have multiple fuel maps, commonly meant to improve performance or fuel
efficiency under certain operating conditions. CO2 emissions can also be different depending on
which map is tested, so it is important to specify a procedure to properly deal with engines with

-------
multiple fuel maps. Consistent with criteria-pollutant emissions certification, engine
manufacturers will be required to address this during certification, either by declaring worst case
maps that cover more than one in-use map, or by submitting multiple fuel maps. The agencies
may require the manufacturer to include other fuel map information, such as when the conditions
under which a given fuel map is used {i.e. transmission gear, vehicle speed, etc.).
3.1.2.6 Measuring GEM Engine Inputs
To recognize the contribution of the engine in GEM, the engine fuel map, full load torque
curve and motoring torque curve have to be input into GEM. To insure the robustness of each of
those inputs, a standard procedure has to be followed. Both the full load and motoring torque
curve procedures are already defined in 40 CFR part 1065 subpart F for engine testing.
However, the fuel mapping procedures we are finalizing are new. The agencies have compared
the new procedures to other accepted engine mapping procedures with a number of engines at
various labs including EPA's NVFEL, Southwest Research Institute, and Environment Canada's
laboratory. The procedure was selected because it proved to be accurate and repeatable, while
limiting the test burden to create the fuel map. This provision is consistent with NAS's
recommendation (3.8).
The agencies are requiring that engine manufacturers must certify fuel maps as part of
their certification to the engine standards, and that they provide those maps to vehicle
manufacturers. These maps consist of steady-state and cycle average fuel maps. The one
exception to this requirement would be for cases in which the engine manufacturer certifies
based on powertrain testing, as described in Chapter 3.6. In such cases, engine manufacturers
would not be required to also certify the otherwise applicable fuel maps. We are not allowing
vehicle manufacturers to develop their own fuel maps for engines they do not manufacture.
In addition to the steady-state engine fuel map procedure for cruise cycles the agencies
are also requiring use of the cycle-average engine map test procedure for the transient duty-cycle
as defined in 40 CFR 1036.540. The cycle-average approach can optionally be used in place of
the steady-state fuel maps by performing cycle-average testing over the cruise cycles. The
NPRM to this rule, along with the two journal publications, one from the US EPA and one
authored by an industry group, discussed in length the benefits of this test procedure.2'3 The
benefits ranged from capturing transient fueling to protecting intellectual property. We have
tested four different engines with two different engine ratings for each engine since the proposal.
The results of these tests confirmed our earlier findings that the cycle average engine test
procedure is much more accurate than the steady-state mapping procedure with respect to
representing the engine over transient engine operation. The results also showed that the cycle
average engine map can be applied to the cruise cycles but required that the agencies update the
test points to ensure that overlap doesn't occur. Overlap happens when the lower axle ratio
causes the vehicle to operate in the next lowest gear at increased engine speed. The agencies
updated the test points in 40 CFR 1037.540 to address the overlap issue. The agencies are
finalizing the requirement to use the steady-state engine procedure over the cruise cycles and the
cycle average engine map procedure for the transient cycle (optional for cruise).
Along with testing additional engines, the agencies have done significant work to define
the mathematical form the cycle average engine map data should take in GEM. The first

-------
approach the agencies evaluated was an interpolation and extrapolation scheme.4 Since then we
have looked at many different least square fits of the data using different dependent (fuel mass
and BSFC) and independent (average engine speed, average engine torque, average engine speed
divided by average vehicle speed (N/V) and positive cycle work) variables. The results of this
work showed that the cycle average map is most accurately described with fuel mass as the
dependent variable and N/V and positive work as the independent variables. The form of the
equation is fuel mass ~ 1 + N/V + W.
3.1.3 Engine Family Definition and Test Engine Selection
3.1.3.1	Criteria for Engine Families
The current regulations outline the criteria for grouping engine models into engine
families sharing similar emission characteristics. A few of these defining criteria include bore-
center dimensions, cylinder block configuration, valve configuration, and combustion cycle; a
comprehensive list can be found in 40 CFR 86.096-24(a)(2). While this set of criteria was
developed with criteria pollutant emissions in mind, similar effects on CO2 emissions can be
expected. For this reason, this methodology should continue to be followed when considering
CO2 emissions, just as it was in the Phase 1 rules.
3.1.3.2	Emissions Test Engine
Manufacturers must select at least one engine per engine family for emission testing. The
methodology for selecting the test engine(s) should be consistent with 40 CFR 86.096-24(b)(2)
(for heavy-duty Otto cycle engines) and 40 CFR 86.096-24(b)(3) (for heavy-duty diesel engines).
An inherent characteristic of these methodologies is selecting the engine with the highest fuel
feed per stroke (primarily at the speed of maximum rated torque and secondarily at rated speed)
as the test engine, as this is expected to produce the worst-case crit