GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 417

aftermarket equipment. See gmupfitter.com for
additional pick-up box load bearing structural
information.
Before installing a snow plow on the vehicle, here are
some things you need to know:
Some vehicles are built with a special snow plow prep
package, called RPO VYU. If your vehicle has this
option, you can add a plow to it, provided certain
weights, such as the weights on the vehicle's axles and
the Gross Vehicle Weight (GVW), are not exceeded.
The plow the vehicle can carry depends on many
things, such as:
The options the vehicle came with, and the weight
of those options.
The weight and number of passengers you intend
to carry.
The weight of items added to the vehicle, like a
tool box or truck cap.
The total weight of any additional cargo you intend
to carry.
Say, for example, you have a 318 kg (700 lb) snow plow.
The total weight of all occupants and cargo inside the
cab should not exceed 135 kg (300 lb). This means that
you may only be able to carry one passenger. But, even
this may be too much if you have got other equipment
already adding to the weight of the vehicle.
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