GMC 2007 Yukon XL Owner's Manual page 413

But let's say your specific vehicle is equipped with
some of the latest options and you have a front
seat passenger and two rear seat passengers with
some luggage and gear in the vehicle as well.
You may add 300 lbs (136 kg) to the front
axle weight and 400 lbs (181 kg) to the rear axle
weight. Your vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
may think that you should subtract 700 additional
pounds (318 kg) from your trailering capacity
to stay within GCWR limits. Your maximum trailer
would only be 7,800 lbs (3 538 kg). You may
go further and think you must limit tongue weight
to less than 1,000 lbs (454 kg) to avoid
exceeding GVWR. But, you must still consider the
effect on the rear axle. Because your rear axle
now weighs 3,100 lbs (1 406 kg), you can only put
900 lbs (408 kg) on the rear axle without
exceeding RGAWR.
The effect of tongue weight is about 1.5 times the
actual weight. Dividing the 900 lbs (408 kg) by
1.5 leaves you with being able to handle only
600 lbs (272 kg) of tongue weight. Since tongue
weight is usually at least 10 percent of total loaded
trailer weight, you can expect that the largest
trailer your vehicle can properly handle is
6,000 lbs (2 721 kg).
It is important that you make sure your vehicle
does not exceed any of its ratings — GCWR,
GVWR, RGAWR, Maximum Trailer Rating
or Tongue Weight. The only way to be sure you
are not exceeding any of these ratings is to weigh
your vehicle and trailer.
Total Weight on Your Vehicle's Tires
Be sure your vehicle's tires are inflated to the
upper limit for cold tires. You'll find these numbers
on the Certification label at the rear edge of the
driver's door or see Loading Your Vehicle on
page 390 for more information. Then be sure you
don't go over the GVW limit for your vehicle,
or the GAWR, including the weight of the trailer
tongue. If you use a weight distributing hitch, make
sure you don't go over the rear axle limit before
you apply the weight distribution spring bars.
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