GMC 2002 Savana Van Owner's Manual page 312

If your vehicle has dual rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
When you install dual wheels, be sure the vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front and rear
inflation pressures as shown on the Certification/Tire
label. Make certain that all wheel nuts are properly
tightened. See "Wheel Nut Torque" in the Index.
CAUTION:
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 a 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.
6-45