2011 Chevrolet Impala Owner's Manual - Page 306

10-50 Vehicle Care How to Check Use a good quality pocket-type gauge to check tire pressure. You cannot tell if the tires are properly inflated simply by looking at them. Radial tires may look properly inflated even when they are underinflated. Check the tire's inflation pressure when the tires are cold. Cold means the vehicle has been sitting for at least three hours or driven no more than 1.6 km (1 mi). Remove the valve cap from the tire valve stem. Press the tire gauge firmly onto the valve to get a pressure measurement. If the cold tire inflation pressure matches the recommended pressure on the Tire and Loading Information label, no further adjustment is necessary. If the inflation pressure is low, add air until you reach the recommended amount. If you overfill the tire, release air by pushing on the metal stem in the center of the tire valve. Re‐check the tire pressure with the tire gauge. Be sure to put the valve caps back on the valve stems. They help prevent leaks by keeping out dirt and moisture. For additional information regarding how much weight the vehicle can carry, and an example of the Tire and Loading Information label, see Vehicle Load Limits on page 9‑12. How you load the vehicle affects vehicle handling and ride comfort. Never load the vehicle with more weight than it was designed to carry. When to Check Check the tires once a month or more. Do not forget to check the compact spare tire, if the vehicle has one. The compact spare should be at 420 kPa (60 psi). For additional information regarding the compact spare tire, see Compact Spare Tire on page 10‑74.