GMC Sierra 2010 Owner's Manual page 409

The total cargo load must not be more than your
vehicle's CWR.
Refer to the Truck-Camper Loading Information
label in the glove box for dimensions A and B as
shown in the following illustration.
Use the rear edge of the load floor for
measurement purposes. The recommended
location for the cargo center of gravity is at
point C for the CWR. It is the point where the
mass of a body is concentrated and, if suspended
at that point, would balance the front and rear.
Here is an example of proper truck and camper
match:
Camper Center of Gravity
A.
Recommended Center of Gravity
B.
Location Zone
When the truck is used to carry a slide in camper,
the total cargo load of the truck consists of the
manufacturer's camper weight figure, the weight of
installed additional camper equipment not
included in the manufacturer's camper weight
figure, the weight of camper cargo, and the weight
of passengers in the camper. The total cargo load
should not exceed the truck's cargo weight rating
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