Knowing your tire pressure

Believe it or not, tire pressure is a pretty big deal—it can affect your gas mileage, ride comfort, tire life, and most importantly, your safety and the safety of everyone else in your vehicle. After the brakes, your tires are actually your vehicle’s most important safety equipment!

How often do I need to check tire pressure?

Since tire pressure is so important, we recommend that you check your tires at least once a month, or even more frequently if you can. The good news is it only takes a few minutes. But before you can check your tires, you’ll need to know your vehicle’s recommended tire pressure.

Where to find your vehicle’s recommended tire pressure

Every tire's sidewall identifies a maximum cold inflation pressure, but that’s not necessarily the correct pressure to use for your vehicle. Vehicle manufacturers predetermine the best tire inflation pressure for each vehicle, so you should follow the manufacturer's recommendation. To find this, first check your vehicle owner's manual. In many cases, you’ll find tire pressure recommendations here, and sometimes the manufacturer may also specify alternate pressures based on load and/or speed.

Another place to find tire inflation information is on the vehicle's tire information placard. Beginning in 2003, vehicle manufacturers were directed to standardize the format and placement of tire information placards.

On new vehicles, the placard must be located on the “B-pillar,” which is the driver's side doorjamb. For vehicles that do not have a B-pillar, the placard should be attached to the rear edge of the driver's door, unless it’s too narrow, in which case it should be placed on an inward-facing surface next to the driver's seat. On older vehicles, look for placards in these locations:

• The driver-side door or doorjamb

• Rear passenger doorjamb of Ford sedans

• Fuel filler door

• Glove box or center console door

• The engine compartment

The tire information placard will tell you the vehicle’s weight capacity, the OE (Original Equipment) tire sizes (including the spare tire), and the recommended inflation pressures for the tires.

Check tires when they’re chilly

Now that you’ve found the recommended cold tire inflation pressure and vehicle load, it’s important to understand how temperature can affect the reading. Tire inflation pressure should be checked first thing in the morning when the tires are at their coldest—before the vehicle has been driven, before the tires have been in direct sunlight, and before the temperature rises. For more details, see our article on Tire Inflation Pressure and Temperature.

More tire pressure tips

• Always use a quality tire gauge to measure tire inflation pressure.

• Don’t rely on a visual check—it simply isn’t possible to measure tire pressure this way.

• Check all four tires. Just because the first two are good to go doesn’t mean they all are.

• Going on a road trip? Check your tire pressure before you take off.

• Check the pressure of your spare tire every once in a while, too. If you have a “space saver” spare, use the pressure rating on the sidewall of the tire.

That’s pretty much everything you need to know about tire inflation pressure. Just remember how important tire pressure is, and be sure to check your tires at least once a month!

Image credit: ThenAndAgain, garrydolley