GMC 2002 Savana Van Owner's Manual page 310

Inflation -- Tire Pressure
The Certification/Tire label, which is on the rear edge of
the driver's door, 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:
D
Too much flexing
D
Too much heat
D
Tire overloading
D
Bad wear
D
Bad handling
D
Bad fuel economy
NOTICE: (Continued)
NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
D
Unusual wear
D
Bad handling
D
Rough ride
D
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.
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