GMC Sierra 2005 Owner's Manual page 501

5. Raise the tire part way upward. Make sure the
retainer is seated in the wheel opening.
6. Raise the tire fully against the underside of the
vehicle by turning the wheel wrench clockwise
until you hear two clicks or feel it skip twice. You
cannot overtighten the cable.
4. Insert the hoist end (F)
through the hole (G) in
the rear bumper
and into the
hoist shaft.
7. Make sure the tire is stored securely. Push, pull, (A)
and then try to turn (B) the tire. If the tire moves,
use the wheel wrench to tighten the cable.
8. Reinstall the spare tire lock (if equipped).
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