Driver’s might recognize the display message “Remember to Keep your Tires Inflated” on highway patrol boards more frequently this time of year as changes in temperature can negatively impact the safety of your vehicles tires.

Checking the air pressure in your tires is a crucial component to car maintenance and safety, especially during the summer months when the temperatures are higher and the road trips are typically longer. Tires need to be properly inflated to maximize handling, traction, and durability. Tire pressure increases as the outside temperature rises, and in some cases, that increase in pressure is enough to cause a blow out! The warmer weather creates heat-build up in the tire, causing it to weaken, and adversely, can also affect the fuel economy of the vehicle. Over-inflated tires can become rigid and inflexible making them more susceptible to damage from road debris and potholes. About 600 deaths and 33,000 injuries occur each year in the U.S. due to improper inflation of tires.

Most vehicle manufacturers have a recommended psi (pounds per square inch) for tire inflation either on the sticker inside the driver’s door or in the owner’s manual. Recommended tire pressure is based on cold inflation pressure, so it should be checked in the morning before the tire has been run, before the temperature rises and before the tire is exposed to direct sunlight.

A good estimate to use when comparing tire pressure to air temperature is for every 10 degrees F, tire pressure will adjust by 1 psi. For example, if the outside air temperature increases 10 degrees, the tire pressure will increase by 1 psi. Conversely, if the air temperature falls 10 degrees, the tire pressure will decrease by 1 psi. In most parts of North America, the difference between average summer temperatures and average winter temperatures is about 50 degrees F. This means that your tires will fluctuate approximately 5 psi between the coldest and warmest times of the year. A drop of 5 psi during colder months will affect traction, handling, and durability.

Regardless of the time of the year, you should regularly check and maintain the regular PSI for your vehicle. Here are some tips the NHTSA recommends to prevent tire failure:

  • Follow the recommended tire pressure in pounds-per-square-inch (PSI) for your vehicle. This information is found on the vehicle placard typically inside the car door and in the vehicle owner’s manual.
  • Purchase a tire pressure gauge to keep in your vehicle. Tires lose one PSI every month, so it is important to check your tires monthly to ensure proper inflation.
  • If your vehicle is equipped with tire pressure monitoring systems (TPMS), know where the TPMS warning is on your dashboard, and take action if you receive a warning.
  • Check your vehicle owner’s manual for specific recommendations for tire replacement for your vehicle. Some vehicle manufacturers recommend six years, some tire manufacturers recommend 10 years as the maximum service life for tires, including spares.
  • Monitor the tread on all tires on your vehicle. Tires with tread worn down to 2/32 of an inch or less are not safe and should be replaced.
  • Look for treadwear indicators – raised sections spaced throughout the bottom of the tread grooves. When they appear it is time to replace your tires.
  • Try the penny test. Place a penny in the tread of your tires with Lincoln’s head upside down and facing you. If you can see the top of Lincoln’s head, your tire has less than 2/32 of an inches of tread and you are ready for new tires.
  • Remember that seat belts are your best defense in a crash.