SmartWay
U.S. Environmental Protection Agency*
Automatic Tire Inflation Systems
A Glance at Clean Freight Strategies
ENERGY &
FUEL SAVINGS
Gallons Saved:
100 gallons
C02 Savings:
1.12 metric tons
Increase in
Fuel Economy:
.604%
MPG:
6.03 mpg
Fuel Cost Savings:
$380
Automatic tire inflation systems can save tire maintenance costs and improve fuel
economy by nearly i percent, saving 100 gallons of fuel and eliminating
1 metric ton of greenhouse gas emissions per year. Properly inflated tires also have
fewer punctures and a longer life expectancy
What is the challenge?
When not properly inflated, tires flex more under load. This produces heat and increases roll-
ing resistance, which wastes fuel. Truck tires inflated 1 0 pounds per square inch (psi) below
recommended air pressure levels can reduce truck fuel economy between 0.5 percent and 1
percent. Since the bulk of the load is carried in the trailer, a 10-psi underinflation in a trailer tire
may have nearly twice the impact on truck fuel economy as the same amount of underinflation in
a drive tire.
Heat and stress from improper inflation softens and deflects tire components, causing faster and
more uneven wear, which shortens the life of the tire. Underinflated tires have more frequent
punctures, increasing the risk of tire failures that could lead to costly road service and loss of
revenue.
Despite the importance, a recent survey of combination trucks found that less than half the tires
surveyed were within 5 percent of the recommended inflation pressure. Another industry survey
indicates only 8 percent of truck drivers check tire pressure with a tire gage before each trip.
One reason fleets may find it difficult to keep tires properly inflated is because truck tires can
lose up to 2 psi each month, even if the rim seal and valve stems are tight. A fleet may not be
able to inspect or monitor its' trailer tires regularly due to the fact that extended periods of time
are spent away from service yards and because trailers are interchangeable. This places greater
responsibility for checking tire pressure onto drivers.
What is the solution?
Automatic tire inflation (ATI) systems monitor and continually adjust the level of pressurized air in
tires, maintaining proper tire inflation automatically even while the truck is in motion. One ATI
system uses the vehicle's own air-brake compressor to supply air to all the tires. Once an ATI
system is installed, it should not require any special attention from the drivers. This eliminates the
need to check tire pressure manually, which saves time and labor while ensuring consistent and
proper tire inflation.
Savings and Benefits
ATI systems can not only extend tire life but truck fleets can also see additional
savings from reducing the risk of expensive tire failure caused by underinflation.
Installing an ATI system on a truck's drive axles and trailer costs up to $800.
For a typical long-haul combination truck, annual fuel savings could
reach 100 gallons, saving $380 in fuel costs and eliminating 1 metric
ton of greenhouse gas emissions. Annual tire maintenance costs can
also decrease. The cost of installing an ATI system in a long-haul truck is
generally recouped in just over 2 years through fuel and maintenance
cost savings.
Continued
U.S. EPA SmartWay | EPA-420-F-16-026 | June 2016 | www.epa.gov/smartway

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^\xSmartWay
U.S. Environmental protection Agency J
Automatic Tire Inflation Systems
A Glance at Clean Freight Strategies Continued
next steps
1 Long-haul carriers
that evaluate their
fleets and determine
it is too difficult or
expensive to moni-
tor tire pressure on
a regular basis can
consider installing
automatic tire pres-
sure inflation systems
on drive and trailer
tires.
2interested fleets
can check with ATI
manufacturers and
truck and tire dealers
for more information.
ATls can be read-
ily retrofitted onto
existing trucks and
trailers.
3Fleets can also
contact tire manu-
facturers or their
state or national
trucking associations
for more information
about the benefits of
proper tire inflation.

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