Find the recommended tire pressure for your vehicle (driver door jamb, owner’s manual, or fuel door sticker)
Check tire pressure when tires are cold (before driving or after sitting at least 3 hours)
Remove the valve cap from one tire
Press a tire pressure gauge firmly onto the valve stem
Read the PSI on the gauge
Compare the reading to the recommended PSI
Add air if the pressure is low (use an air compressor, then recheck)
Release air in small amounts if the pressure is high (then recheck)
Repeat for every tire, including the spare if it’s intended for road use
Put the valve caps back on
Recheck after any adjustment to confirm the final PSI matches the recommended range