GMC 2011 Sierra Denali Owner's Manual page 419

2. Remove the center cap by
placing the chisel end of the
wheel wrench in the slot on the
wheel and gently prying the
cap out.
3. Use the wheel wrench to loosen
all the wheel nuts. Turn the
wheel wrench counterclockwise
to loosen the wheel nuts. Do not
remove the wheel nuts yet.
Vehicle Care
WARNING
Getting under a vehicle when it is
jacked up is dangerous. If the
vehicle slips off the jack, you
could be badly injured or killed.
Never get under a vehicle when it
is supported only by a jack.
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