Would you like to save money on gasoline and extend the life of your tires? Pima County Department of Environmental Quality's Clean Air Program recommends checking your tire pressure when there is a big drop in outside temperatures. Our science teachers taught us that air expands when heated and contracts when chilled, which means there is a lot less air pressure in your tires when the temperatures drop during the fall and winter seasons.
For every 10 degree Fahrenheit change in air temperature, tire pressure will change about two percent, or about 1-to-2 two pounds per square inch (PSI). This can result in a drop of about 5 PSI in the winter, which is enough to negatively affect vehicle handling, traction, gas mileage and tire durability. Monthly tire pressure checks, along with a special tire-pressure check when temperatures drop when the seasons change, will improve driving safety and save you money at the gas pump.
Where do you find the correct tire pressure for your particular vehicle? Don’t look for it on the side wall of the tire. That number is the maximum amount of air the tire can hold. Every vehicle has its own ideal PSI, which is usually printed on the inside the driver’s side door jamb, inside the trunk or in the glove box. This number also can be found in the owner’s manual. Maintaining your tires at the right pressure will:
- provide a smoother ride
- reduce tire drag, which wears tires out faster and causes the engine to burn more gasoline
- save you money at the gas station
- reduce vehicle emissions for healthier air
For more information on the benefits of proper tire inflation, visit the Pima County Department of Environment Quality’s Pump Up Your MPG program.