Maximum tire pressure on the sidewall — what does it mean?
Every tire lists a maximum inflation pressure on the sidewall. The pressure is the most you should inflate the tire to when it’s cold. “Cold” is defined as: early in the morning before the temperature has reached the day’s highest ambient temperature, or the sun’s radiant heat or the heat generated while driving have caused the tire pressure to temporarily increase. The maximum inflation pressure shown on the sidewall represents the highest pressure the tire is designed to contain.
That does NOT mean it’s the recommended pressure! The recommended pressure is listed on the vehicle’s tire placard or in the vehicle’s owner’s manual. The recommended pressure is also calculated when the tire is cold.
Hot tire pressures are usually 5 to 6 psi above the tire’s recommended “cold” pressure and are usually found after driving the vehicle for a while or if the vehicle has been parked in the sun. If you’ve set the “cold” tire pressure was correct, do not bleed off the higher pressure found when the vehicle is hot.
Posted on by Rick Muscoplat