SmartWay Transport | EPA420-F11-005 | www.epa.gov/smartway | 734-214-4767 | smartway_transport@epa.gov

Maintaining Proper Tire Inflation Pressure

A Glance at Clean Freight Strategies

Energy

and 

Fuel Savings

Gallons Saved 

= 

100 gallons

Increase in Fuel 

Economy 

= 

.6%

New MPG

= 

6.04 mpg

Fuel Cost Savings

= 

$346

CO2 Savings 

= 

1.02 Metric tons

1 Trucking companies 

can contact tire manufacturers or their state or 

national trucking associations for more information about the benefits 

of keeping tires properly 

inflated.

2 Fleet operation 

managers can consider 

installing automatic 

tire pressure inflation 

systems on drive and 

trailer tires to help 

maintain proper tire 

inflation pressure 

while trucks are on the 

road.

3 Interested fleets can 

check with equipment 

manufacturers and 

truck and tire dealers 

for more information on 

ATI, nitrogen fill or other 

technologies developed 

to enhance tire maintenance and ensure proper 

tire inflation pressure. 

Next Steps

.

Maintaining proper tire inflation pressure can save tire maintenance costs 

and improve fuel economy by nearly 1 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 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 percent and 1 

percent. 

Heat and stress from improper inflation soften and deflect tire components, causing faster 

and more uneven wear, which shorten 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 of proper tire inflation pressure, 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 that 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?

One way to prevent tire pressure underinflation is for fleets to have tire maintenance management systems in place to ensure that drivers and equipment maintenance personnel 

check tire pressure at frequent intervals and fill tires that are underinflated. This can be made 

easier by the use of electronic tire pressure monitoring systems that signal to drivers and 

maintenance personnel when a tire becomes underinflated. 
Maintaining Proper Tire Inflation Pressure

SmartWay Transport | EPA420-F11-005 | www.epa.gov/smartway | 734-214-4767 | smartway_transport@epa.gov

Automatic tire inflation (ATI) systems monitor and continually adjust the level of pressurized air in tires, maintaining 

proper tire inflation automatically 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.

There is some evidence that loss of tire inflation pressure can be slowed by using nitrogen gas instead of air to inflate 

tires. While this method is not recommended as a substitute for regular checks of tire pressure, testing by the U.S. 

Department of Transportation has shown that nitrogen inflation reduces the rate of pressure loss.

Savings and Benefits 

ATI systems can not only extend tire life but truck fleets can also offer additional savings from reducing the risk of 

expensive tire failure caused by underinflation. Installing an ATI system on a truck’s drive and trailer axles costs up 

to $800. For a typical long-haul combination truck, annual fuel savings could reach 100 gallons, saving $346 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.

There have been no scientific studies to document fuel savings obtained through the use of nitrogen inflation, but 

anecdotal reports indicate some fleets are seeing benefits from this approach. One large national fleet reported to a 

panel of the National Academy of Sciences that it observed a 1 to 1.5 percent reduction in fuel use after using a nitrogen inflation system. Additionally, nitrogen inflation systems typically remove oxygen and water from the inflation gas; 

both oxygen and water can contribute to tire aging.

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