GMC 2003 Sierra 1500 Pickup Owner's Manual page 351

Vehicle"
I
Axle Ratio
I
Maximum Trailer Weight
I
GCWR
(C-I500 Extended Cab Short Box 2WD
*
15 percent of trailer weight up to 1,000 Ibs (454 kg). Fifth-wheel or gooseneck kingpin weight 15 percent to
25 percent of trailer weight up to 1,500 Ibs. (680 kg) maximum.
**Maximum 8,000 Ibs. (3 628 kg) for fifth-wheel or gooseneck.
***Maximum 7,500 Ibs. (3 401 kg) for fifth-wheel or gooseneck.
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