Transport Partnership
U.S. ENVIRONMENTAL PROTECTION AGENCY
Energy
and
Fuel Savings
Rocky Mountain Doubles
I Gallons Saved I
2166 gallons
Fuel Savings
Fuel Cost Savings
Turnpike Doubles ft Triples
I Gallons Saved I
3 500 gallons
Fuel Savings
Fuel Cost Savings
$13,300
Longer Combination Vehicles
A Glance at Clean Freight Strategies
Increasing the cargo capacity of combination trucks by using longer or multiple
trailers can save fuel and reduce greenhouse gas emissions by up to 34 metric
tons per year.
What is the challenge?
The amount of cargo that a typical combination truck can carry is limited by its trailer capacity.
Atypical combination truck consists of a three-axle tractor pulling a two-axle, 53 foot trailer,
with the capacity to carry approximately 3,800 cubic feet and 45,000 pounds of cargo.
What is the solution?
Longer combination vehicles (LCVs) are combination trucks with multiple trailers and/or
longer trailers than those used with a standard five-axle combination truck. Common configu-
rations are:
Rocky Mountain Double: One trailer up to 53 feet long and one trailer up to 28.5 feet
long, with a combined weight of up to 120,000 pounds
Turnpike Double: Two trailers, each up to 53 feet long with a combined weight of up to
148,000 pounds
Triple: Three trailers, each up to 28.5 feet long with a combined weight of up to 132,000
pounds
Eight-Axle Twin Trailer: Two trailers, each up to 33 feet long with a total of eight axles and
a combined weight of up to 124,000 pounds
The extra capacity that LCVs provide enables truck fleets to haul the same amount of cargo
with fewer trips. LCVs have slightly lower fuel economy, as measured in miles per gallon,
than typical combination trucks. However, because LCVs carry more cargo per trip, they
require less fuel to haul a ton of freight one mile. This measure of fuel economy is called a
ton-mile. LCVs generally have much better ton-mile fuel economy than other combination
trucks. Since only part of a truck's fuel consumption is used to overcome mass, the percent
increase in LCV ton-miles exceeds the percent increase in LCVfuel consumption. Increased
productivity cuts fuel consumption and reduces greenhouse gas and air pollutant emissions.
The environmental benefits could be slightly mitigated if LCV use rises at the expense of
freight train use, since freight trains are generally more fuel-efficient and have lower emis-
sions per ton-mile than freight trucks.
Federal and state laws specify truck size and weight limits. A1991 federal law prevents
t/3
Q.
0>
i/5
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I Trucking firms should
consider use of LCVs on
routes where their use is
allowed and appropriate.
2 For more informa-
tion on what types of
vehicle configurations
are allowed in each state,
contact your state or
federal department of
transportation, or your
state or national trucking
association.
SmartWay Transport | EPA420F10-053 | www.epa.gov/smartway | 734-214-4767 | smartway_transport@epa.go
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Longer Combination Vehicles
LCV expansion into states that did not permit these vehicles before the law's passage. Longer combination vehicles
currently operate in 16 states west of the Mississippi River and on turnpikes in 5 states east of the Mississippi River.
Twenty-nine states do not allow LCVs. Of the states in which LCVs operate, 11 allow operation of triples, 8 allow
triples with permits, and 8 allow Rocky Mountain Doubles. Three states allow operation of these LCVs without restric-
tions.
Additional factors may influence the more widespread use of LCVs. LCVs have inherent stability and control limita-
tions because of their length and number of trailers. Therefore, it is important that only experienced drivers under safe
conditions operate LCVs. Widespread use of LCVs could have an adverse affect on bridges and other transportation
infrastructure.
Savings and Benefits
LCVs are more fuel-efficient, on a ton-mile basis, than typical combination trucks. For example, a Rocky Mountain
Double consumes 13 percent less fuel per ton-mile of freight, compared to a typical combination truck. This saves
over $8,000 in fuel costs per year. Turnpike Doubles and Triples reduce fuel use per ton-mile by 21 percent, saving
over $13,000 in annual fuel costs.
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SmartWay Transport | EPA420F09-xxx | www.epa.gov/smartway | 734-214-4767 | smartway_transport@epa.gov
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