GMC 2004 Sierra 1500 Pickup Owner's Manual page 363

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CAUTION:
On some vehicles equipped with certain front
mounted equipment, such as a snow plow, it
may be possible to load the front axle to the
front GAWR but not have enough weight on
the rear axle to have proper braking
performance. If your brakes can not work
properly, you could have a crash. To help your
brakes work properly when a snow plow is
installed, always follow the snow plow
manufacturer or installer's recommendation for
rear ballast to ensure a proper front and rear
weight distribution ratio, even though the
actual front weight may be less than the front
GAWR, and the total vehicle weight is less
than the GVWR. Maintaining a proper front and
rear weight distribution ratio is necessary to
provide proper braking performance.
Q:
What is total vehicle reserve capacity?
A:
This is the difference between your GVWR and
the weight of your truck with full fuel and
passengers. It is the amount of weight you can
add to your vehicle before reaching your GVWR.
Keep in mind that reserve capacity numbers
are intended as a guide when selecting the amount
of equipment or cargo your truck can carry. If
you are unsure of your truck's front, rear or total
weight, go to a weigh station and weigh your
vehicle. Your dealer can also help you with this.
The total vehicle reserve capacity for your vehicle
can be found in the lower right corner of the
Certification/Tire label as shown previously.
See your dealer for additional advice and information
about using a snow plow on your vehicle. Also,
see Loading Your Vehicle on page 4-57 .
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