2002 Pontiac Firebird Owner's Manual - Page 293

Inflation -- Tire Pressure The Tire-Loading Information label, which is on the rear edge of the driver's door, shows the correct inflation pressures for your tires when they're cold. "Cold" means your vehicle has been sitting for at least three hours or driven no more than 1 mile (1.6 km). If you'll be driving at high speeds (e.g., speeds of 100 mph (160 km/h) or higher), where it is legal, set the cold inflation pressure to the maximum inflation pressure shown on the tire sidewall, or to 38 psi (265 kPa), whichever is lower. See the example below. When you end this high-speed driving, return to the cold inflation pressure shown on the Tire-Loading Information label. Example: You'll find maximum load and inflation pressure molded on the tire's sidewall, in small letters, near the rim flange. It will read something like this: Maximum load 690 kg (1521 lbs.) @ 300 kPa (44 psi) Max. Press. For this example, you would set the inflation pressure for high-speed driving at 38 psi (265 kPa). NOTICE: Don't let anyone tell you that underinflation or overinflation is all right. It's not. If your tires don't have enough air (underinflation), you can get the following: D Too much flexing D Too much heat D Tire overloading D Bad wear D Bad handling D Bad fuel economy If your tires have too much air (overinflation), you can get the following: D Unusual wear D Bad handling D Rough ride D Needless damage from road hazards 6-47