GMC 1998 Savana Van Owner's Manual page 282

Inflation
--
Tire Pressure
The Certificationflire 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 hav.2 enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
0
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
NOTICE:
(Continued)
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
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