Buick 2007 Rendezvous - Manual (Page 343)

If you are using a weight-carrying or weight
distributing hitch, the trailer tongue weight (A)
should be 10 percent to 15 percent of the
total loaded trailer weight (B). Do not exceed the
maximum allowable tongue weight for your
vehicle.
After you have loaded your trailer, weigh the trailer
and then the tongue, separately, to see if the
weights are proper. If they are not, you may be
able to get them right simply by moving some
items around in the trailer.
Trailering may also be limited by the vehicle’s
ability to carry tongue weight. Tongue weight
cannot cause the vehicle to exceed the GVWR
(Gross Vehicle Weight Rating) or the RGAWR
(Rear Gross Axle Weight Rating). The effect
of additional weight may reduce your trailering
capacity more than the total of the additional
weight.
Consider the following example:
A vehicle model base weight is 5,500 lbs
(2 495 kg); 2,800 lbs (1 270 kg) at the front axle
and 2,700 lbs (1 225 kg) at the rear axle. It
has a GVWR of 7,200 lbs (3 266 kg), a RGAWR
of 4,000 lbs (1 814 kg) and a GCWR (Gross
Combination Weight Rating) of 14,000 lbs
(6 350 kg). The trailer rating should be:
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