SmartWay
U.S. Environmental Protection Agency +
Automatic Tire Inflation Systems
A Glance at Clean Freight Strategies
ENERGY & FUEL SAVINGS
Gallons saved:
100
gallons
CO2 savings:
1.0
metric tons
Fuel Economy
Increase:
0.6%
MPG (originaL 6 mpg):
6.04
mpg
Fuel Cost Savings:
$290
Automatic tire inflation systems can save tire maintenance costs and improve fuel
economy by nearly l percent, saving 100 gallons of fuel and eliminating l 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
rolling resistance, which wastes fuel. Truck tires inflated 10 pounds per square inch (psi)
below recommended air pressure levels can reduce truck fuel economy between 0.5 %
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
gauge 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.
EPA-420-F-19-018 | August 2019 | SmartWay Transport Partnership | epa.gov/smartway
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Automatic Tire Inflation Systems: A Glance at Clean Freight Strategies (continued)
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 $290 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 under 3 years through fuel and
maintenance cost savings.
100
Gallons in annual
fuel savings
~
NEXTSTEPS
1
2
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Long-haul carriers that evaluate their fleets and determine it is too difficult or expensive to monitor
tire pressure on a regular basis can consider installing automatic tire pressure inflation systems on
drive and trailer tires.
Interested fleets can check with ATI manufacturers and truck and tire dealers for more information.
ATls can be readily retrofitted onto existing trucks and trailers.
Fleets can also contact tire manufacturers or their state or national trucking associations for more
information about the benefits of proper tire inflation.

Please visit the SmartWay website at www.epa.gov/smartway
to access more tech bulletins.
SmartWay
U.S. Environmental Protection Agency^

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