Chevrolet Express Owner's Manual page 331

6. Remove all the wheel nuts.
7. Take the flat tire off of the
mounting surface.
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
make wheel nuts become loose
after time. The wheel could come
off and cause an accident. When
changing a wheel, remove any
rust or dirt from places where the
wheel attaches to the vehicle. In
an emergency, a cloth or a paper
towel can be used; however, use
a scraper or wire brush later to
remove all rust or dirt.
8. Remove any rust or dirt from the
wheel bolts, mounting surfaces,
and spare wheel.
(Continued)
Never use oil or grease on bolts
or nuts because the nuts might
come loose. The vehicle's wheel
could fall off, causing a crash.
9. Put the wheel nuts back on with
the rounded end of the nuts
toward the wheel. Tighten each
wheel nut by hand until the
wheel is held against the hub.