GMC Hummer H3 2008 Owner's Handbook Manual page 318

7. Remove the wheel nuts and
take off the tyre.
8. Remove any dirt or rust from
the wheel bolts, mounting
surfaces and spare wheel.
Section 5
CAUTION
Rust or dirt on the wheel, or on
the parts to which it is fastened,
can make the 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 the places where the
wheel attaches to the vehicle. In
an emergency, you could use a
cloth or a paper towel to do
this; but be sure to use a scraper
or wire brush later, if necessary,
to get all the rust or dirt off.
317 . . .