GMC 2003 Sierra 1500 Pickup Owner's Manual page 361

*
Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 Ibs (680 kg). Fifth-wheel
or
gooseneck kingpin weight should be 15 percent to 25 percent of trailer weight up to 3,000 Ibs. (1 360 kg)
maximum.
**
Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch).
maximum.
** Limited to 12,000 Ibs. (5 443 kg) with weight distributing hitch).
4-80