Pontiac Grand Prix 2007 Owner's Manual page 331

Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1,000 lbs
(454 kg). But even that can be too heavy.
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature, and how much the vehicle is used
to pull a trailer are all important. It can also depend
on any special equipment that is on the vehicle,
and the amount of tongue weight the vehicle
can carry. See "Weight of the Trailer Tongue"
later in this section for more information.
Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it has
all the required trailering equipment. The weight
of additional optional equipment, passengers
and cargo in the tow vehicle must be subtracted
from the maximum trailer weight.
Ask your dealer for our trailering information or
advice, or write us at our Customer Assistance
Ofices. See Customer Assistance Offices on
page 502 for more information.
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important
weight to measure because it affects the total
or gross weight of the vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of the
vehicle, any cargo in it, and the people who will be
riding in the vehicle. If there are a lot of options,
equipment, passengers and cargo in the vehicle,
it will reduce the tongue weight the vehicle
can carry, which will also reduce the trailer weight
the vehicle can tow. And if towing a trailer, the
tongue load must be added to the GVW because
the vehicle will be carrying that weight, too.
See Loading Your Vehicle on page 322 for
more information about your vehicle's maximum
load capacity.
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