2008 GMC Sierra 1500 Pickup Owner's Manual - Page 295

The combined weight of the driver, passengers, and cargo should never exceed your vehicle's capacity weight. Certification/Tire Label Example 3 Item A B C Description Vehicle Capacity Weight for Example 3 = Subtract Occupant Weight 200 lbs (91 kg) × 5 = Available Cargo Weight = Total 1,000 lbs (453 kg) 1000 lbs (453 kg) 0 lbs (0 kg) Refer to your vehicle's tire and loading information label for specific information about your vehicle's capacity weight and seating positions. A vehicle specific Certification/Tire label is found on the rear edge of the driver's door. The label shows the size of your vehicle's original tires and the inflation pressures needed to obtain the gross weight capacity of your vehicle. This is called Gross Vehicle Weight Rating (GVWR). The GVWR includes the weight of the vehicle, all occupants, fuel, and cargo. 4-37