GMC Sierra 2008 Owner's Manual page 341

Example 3
Item Description
Vehicle Capacity
A Weight for
Example 3 =
Subtract Occupant
B Weight 200 lbs
(91 kg) × 5 =
Available Cargo
C
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. The combined weight of the driver,
passengers, and cargo should never exceed
your vehicle's capacity weight.
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