GMC C series 2002 Owner's Manual page 164

Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load your vehicle the right way.
NOTICE:
Your warranty does not cover parts or
components that fail because of overloading.
If you put things inside your vehicle
tools, packages or anything else
the vehicle goes. If you have to stop or turn quickly, or
if there is a crash, they'll keep going.
--
like suitcases,
--
they will go as fast as
CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn,
or in a crash.
D
Put things in the cargo area of your vehicle.
Try to spread the weight evenly.
D
Never stack heavier things, like suitcases,
inside the vehicle so that some of them are
above the tops of the seats.
D
Don't leave an unsecured child restraint in
your vehicle.
D
When you carry something inside the
vehicle, secure it whenever you can.
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