GMC 2005 T-Series Owner's Manual page 143

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: Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
If you put things inside your vehicle – like suitcases,
tools, packages or anything else – they will go as fast as
the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they'll keep going.
CAUTION:
{
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
•
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
•
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
•
Do not leave an unsecured child restraint
in your vehicle.
•
When you carry something inside the
vehicle, secure it whenever you can.
•
Do not leave a seat folded down unless
you need to.
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