Chevrolet 1998 C/K Full-Size Pickup Owner's Manual page 342

Inflation
--
Tire Pressure
The
Certificationflire label, which
is on
the rear edge
of
the driver's door, or on the incomplete vehicle document
in the cab, 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:
0
Too much flexing
0
Too much heat
0
Tire overloading
Bad wear
0
Bad handling
Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
0
Unusual wear
0
Bad handling
Rough ride
0
Needless damage from road hazards.
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