GMC 1993 Safari Owner's Manual page 285

Tire Inspection
and
Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended in the Maintenance Schedule. See "Scheduled
Maintenance Services" in the Index.
RECOMMENDED ROTATION PATTERN
FRONT
Read "Inspection and Rotation" Text for
Additional Information on Tire Rotation.
Do Not Include "Temporary Use Only"
Compact Spare Tire In Rotation.
Use this rotation pattern.
If your vehicle has front tires with different load ratings or tread designs (such
as all season vs. on/off road) than the rear tires, don't rotate your tires front
to rear.
After the tires have been rotated, adjust the front and rear inflation pressure
as shown on the Certification/Tire label. Make certain that all wheel nuts are
properly tightened. See "Wheel Nut Torque" in the Index.
I
CAUTION
A
Rust or dirt on a wheel, or on the parts to which it is fastened, can
make wheel nuts become loose after a time. The wheel could come
off and cause an accident. When you change a wheel, remove any
rust or dirt from places where the wheel attaches to the vehicle. In
an emergency, you can use
a
cloth or paper towel to do this; but be
sure to use a scraper or wire brush later,
if
you need
to,
to get all
the rust or dirt off. (See "Changing a Flat Tire" in the Index.)
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