Ford 1997 Aerostar Manual page 185

Gross Axle Weight Rating (GAWR)
We have all seen a car or a truck that is loaded
down in the rear and riding high in the front.
This is a dangerous condition that usually means
that the rear suspension components are under
severe strain and that vehicle handling is
impaired. There is more to carrying a load than
just payload or GVWR.
Your Safety Compliance Certification Label not
only gives the GVWR, it also gives the Gross
Axle Weight Rating (GAWR) which is the
carrying capacity for each axle system. For
trucks, the rear axle will be designed to carry
more weight than the front.
The rating is based on the carrying capacity of
the lowest rated axle and suspension component
as well as other factors. This is why it's so
important to observe vehicle loading ratings.
Overloading a vehicle punishes components and
can lead to shortened service life or outright
failure.
The capacity of the tires is included as part of
the axle and suspension system, which is to be
considered when determining the lowest rated
component. Tires are rated to carry a specific
maximum load at a specific maximum tire
pressure.
Passenger car type tires when installed on light
trucks and multipurpose passenger vehicles are
rated at 10% lower load carrying capacity due to
the differences in vehicle usages.
The vehicle must not be loaded to both the front
and rear GAWR because the GVWR will be
exceeded. The GAWR of the front and rear axles
exceeds the GVWR when added together to
allow flexibility in fore and aft loading of cargo.
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