Pontiac 2007 G5 Owner's Manual page 259

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.
You can ask your dealer for our trailering
information or advice. Also, see Customer
Assistance Offices on page 397 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 your vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of the
vehicle, any cargo you may carry in it, and
the people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers,
or cargo in your vehicle, it will reduce the tongue
weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow.
And if you tow a trailer, you must add the tongue
load to the GVW because your vehicle will be
carrying that weight, too. See Loading Your
Vehicle on page 249 for more information about
your vehicle's maximum load capacity.
If you are using a weight-carrying hitch, the trailer
tongue (A) should weigh 10 to 15 percent of
the total loaded trailer weight (B).
After you have loaded your trailer, weigh the trailer
and then the tongue, separately, to see if the
weights are proper. If they are not, you may be
able to get them right simply by moving some
items around in the trailer.
259