GMC 2003 GMT560 T-Series, Owner'S Manual, Page: 209 / 284

Inflation -- Tire Pressure
The GVW Rating label, which is on the driver’s door
frame, shows the correct inflation pressures for
your tires when they’re cold. “Cold” means your vehicle
has been sitting for at least three hours or driven no
more than 1 mile (1.6 km).
Notice: Don’t let anyone tell you that underinflation
or overinflation is all right. It’s not. If your tires
don’t have enough air (underinflation), you can get
the following:
•
Too much flexing
•
Too much heat
•
Tire overloading
•
Bad wear
•
Bad handling
•
Bad fuel economy
If your tires have too much air (overinflation), you
can get the following:
•
Unusual wear
•
Bad handling
•
Rough ride
•
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire
(if equipped).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Wheel Loading
Wheels are stamped with a maximum load and cold
inflation rating. Be sure you don’t exceed these. If you
ever think you need to, first contact the rim and
wheel maker to get their advice.
Rims and Wheels
Rims and wheels are stamped with a maximum load
and cold inflation rating. Be sure you don’t exceed
these limits.
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