2004 GMC Savana Van Owner's Manual - Page 311

Vehicle Maximum Load on the Tire: Load on an individual tire due to curb weight, accessory weight, occupant weight and cargo weight. Vehicle Placard: A label permanently attached to a vehicle showing the original equipment tire size and recommended inflation pressure. See Loading Your Vehicle on page 4-31. 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: Inflation - Tire Pressure The tire and loading information label, 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). See Loading Your Vehicle on page 4-31, for the location of your vehicle's tire and loading information label. Too much flexing Too much heat Tire overloading Bad wear Bad handling Bad fuel economy If your tires have too much air (overinflation), you can get the following: Unusual wear Bad handling Rough ride Needless damage from road hazards When to Check Check your tires once a month or more. Also, check the tire pressure of the spare tire. 5-65