2001 GMC Yukon Owner's Manual - Page 348

Inflation -- Tire Pressure The Certification/Tire 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 have an 8600 GVW truck (2500 series) with LT245/75R16E tires, you can improve your ride comfort by reducing tire inflation pressure, but only when carrying reduced loads. If you have a maximum of 8 passengers, and 200 lbs. (90 kg) of load, you can set the front tires at 40 psi (280 kPa), and the rear tires at 50 psi (350 kPa). When using the reduced tire inflation pressure settings, don't exceed the following loading conditions: GVWR - 7900 lbs. (3583 kg), GAWR FRONT - 3730 lbs. (1692 kg), GAWR REAR - 4410 lbs. (2000 kg). When carrying loads greater than 8 passengers and 200 lbs. (90 kg) and/or when pulling a trailer, you must inflate your tires to the pressure shown on the Certification/Tire label. 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. 6-45