Tire Pressure Guide

The right tire pressure keeps your car safer, helps your tires last longer and can save fuel. Here's what you need to know, in plain words.

Where to find the right pressure

Look at the sticker inside the driver's door frame. It lists the recommended cold pressure for the front and rear tires, in PSI. You'll also find it in your owner's manual.

Don't use the number on the tire's sidewall. That's the maximum the tire can hold, not the pressure your car needs.

Check them cold

Driving warms your tires and raises the pressure reading. For an accurate number, check before you drive, or after the car has been parked for a few hours.

How often

Check all four tires about once a month, and before a long road trip. Don't forget the spare, if you have one.

Why your tires lose air when it gets cold

Air contracts as it cools. As a rule of thumb, tire pressure drops about 1 PSI for every 10°F the temperature falls. That's why the low-tire light often comes on during the first cold mornings of the year.

What the low-tire light means

In the US, the tire pressure warning light (TPMS) comes on when a tire is well below its recommended pressure, about 25% low. By the time it lights up, the tire needs air. Top it up to the number on your door sticker, and if the light comes back on soon, have the tire checked for a leak.

Bikes, motorcycles and balls

• Motorcycles: use the pressures in your owner's manual or on the label on the bike.
• Bicycles: the recommended range is printed on the tire's sidewall. Road bikes usually need much more pressure than mountain bikes.
• Sports balls: the recommended pressure is usually printed near the valve.

Low tire, no gas station?

A cordless inflator like ProPump lets you set the exact number from your door sticker and stops on its own when it gets there. See ProPump.