Cadillac 2011 STS Owner's Manual page 447

The tools you will be using include the jack (A) and the
wheel wrench (B).
1. Do a safety check before proceeding. See
information.
2. Loosen all of the wheel nuts, but do not remove
them yet, using the wheel wrench. Turn the handle
about 180 degrees, then flip the handle back to the
starting position. This avoids taking the wrench off
the lug nut for each turn.
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