Chevrolet 2009 Impala Owner's Manual page 334

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 changing a wheel, remove any rust
or dirt from places where the wheel attaches to the
vehicle. In an emergency, use a cloth or a paper
towel to do this; 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 5-76.
5-82
8. Install the compact spare tire.
CAUTION:
{
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.
7. Remove any rust or dirt
from the wheel bolts,
mounting surfaces, and
spare wheel.