The correct tire pressure is typically found on the driver’s door frame, in the glovebox or in the owner’s manual. These pressures are measured when the tires are cold. A good time to check them, is after the vehicle has been sitting for a while. Early morning or late evening works to avoid any additional heat created by the sun.
If you are missing this information or have changed the wheels/tires on your vehicle you can determine your correct tire pressure this way:
Drawer a chalk line across the tire tread and on to the side wall. Drive the vehicle a short distance, park the vehicle and locate the chalk mark. The mark should be worn evenly across the tire.
- If the middle is missing, but the sides are still there, your tires are overinflated and need to have some pressure removed.
- If the outside is missing but the inside is still there, your tires are underinflated and need to have air added.
After adjusting, re-do the chalk mark test. Once you feel the tire is correctly inflated, allow the vehicle to sit and the tires to cool. At that point, measure the tire pressure. This is your cold tire pressure reading.