GMC 2008 Yukon Denali Owner's Manual page 426

6. Take off the flat tire.
CAUTION:
{
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 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;
5-88
5. Remove all of the
wheel nuts.
CAUTION: (Continued)
CAUTION: (Continued)
but be sure to use a scraper or wire brush
later, if needed, to get all the rust or dirt off.
See Changing a Flat Tire on page 5-78.
CAUTION:
{
Never use oil or grease on studs or nuts.
Because the nuts might come loose. The
vehicle's wheel could fall off, causing a crash.
7. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.