Cadillac 2008 DTS Owner's Manual page 377

11. Place the spare tire on the wheel-mounting surface.
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.
12. Put the wheel nuts
back on with the
rounded end of the
nuts toward the wheel.
Tighten each nut by
hand until the wheel is
held against the hub.
13. Lower the vehicle by turning the jack handle
counterclockwise. Lower the jack completely.
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