GMC 2010 Sierra - Manual (Page 441)

Weight of the Trailer Tongue
The tongue load (A) of any trailer is very important
because it is also part of the vehicle weight. The Gross
Vehicle Weight (GVW) includes the curb weight of the
vehicle, any cargo carried in it, and the people who will
be riding in the vehicle as well as trailer tongue weight.
Vehicle options, equipment, passengers and cargo in
the vehicle reduce the amount of tongue weight the
vehicle can carry, which will also reduce the trailer
weight the vehicle can tow. See “Loading the Vehicle”
for more information about the vehicle's maximum load
capacity.
Trailer tongue weight (A) should be 10 percent to
15 percent and fifth wheel or gooseneck kingpin weight
should be 15 to 25 percent of the loaded trailer weight
up to the maximums for vehicle series and hitch type
shown below:
Vehicle Series Hitch Type
Maximum
Tongue Weight
1500 Weight Carrying 272 kg (600 lbs)
2500HD/3500 Weight Carrying 453 kg (1,000 lbs)
1500 Weight Distributing 499 kg (1,100 lbs)
2500HD/3500 Weight Distributing 680 kg (1,500 lbs)
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