2009 Hummer H3T Owner's Manual - Page 287

Service and Appearance Care 5-51 Inflation - Tire Pressure Tires need the correct amount of air pressure to operate effectively. Notice: Do not let anyone tell you that under-inflation or over-inflation is all right. It is not. If your tires do not have enough air (under-inflation), you can get the following: • Too much flexing • Too much heat • Tire overloading • Premature or irregular wear • Poor handling • Reduced fuel economy If your tires have too much air (over-inflation), you can get the following: • Unusual wear • Poor handling • Rough ride • Needless damage from road hazards A vehicle specific Tire and Loading Information label is attached to your vehicle. This label shows your vehicle's original equipment tires and the correct inflation pressures for your tires when they are cold. The recommended cold tire inflation pressure, shown on the label, is the minimum amount of air pressure needed to support your vehicle's maximum load carrying capacity. For additional information regarding how much weight your vehicle can carry, and an example of the Tire and Loading Information label, see Loading the Vehicle on page 4-35. How you load your vehicle affects vehicle handling and ride comfort. Never load your vehicle with more weight than it was designed to carry. When to Check Check your tires once a month or more. Also check the tire pressure of the spare tire. If your vehicle has a compact spare tire, it should be at 60 psi (420 kPa). See Spare Tire on page 5-82 for additional information. How to Check Use a good quality pocket-type gage to check tire pressure. You cannot tell if your 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 your vehicle has been sitting for at least three hours or driven no more than 1 mile (1.6 km).