GMC 1997 Safari Owner's Manual page 206

Payload
The Payload Capacity is shown on the CertificationRire
label. This is the maximum load capacity that your
vehicle can carry. Be sure to include the weight of the
people inside as part of your load. If you added any
accessories or equipment after your vehicle left the
factory, remember to subtract the weight of these things
from the payload. Your dealer can help you with this.
Trailering Package
If your vehicle comes with the Trailering Package, there
is
also
a
load rating which includes the weight of the
vehicle and the trailer it tows. This rating is called the
Gross Combination Weight Rating (GCWR).
When you weigh your trailer, be sure to include the
weight of everything you put in it. And, remember to
figure the weight of the people inside as part of
your load.
Your dealer can help you determine your GCWR.
Add-on Equipment
When you carry removable items, you may need to put a
limit on how many people you carry inside your vehicle.
Be sure to weigh your vehicle before you buy and install
the new equipment.