Chevrolet 2001 Silverado 1500 Pickup Owner's Manual page 273

Q:
What is front axle reserve capacity, and how
do I calculate it?
A:
Front axle reserve capacity is the difference
between your front GAWR and the front axle
weight of your truck with full fuel and passengers.
Basically, it's the amount of weight you can add to
your front axle before reaching your front GAWR.
The front axle reserve
capacity for your
vehicle can be
found in the lower
right corner of the
tire/certification label.
In order to calculate the amount of weight any front
accessory, such as a snow plow, is adding to the
front axle, use the following formula:
(W x (A + W.B))/W.B.= Weight the accessory is
adding to the front axle.
Where:
W=Weight of added accessory
A=Distance that the accessory is in front of the
A=front axle
W.B.=Vehicle Wheelbase
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