GMC Sierra 2011 Owner's Manual page 491

Rear Position All Other Models
For all other models, position the
jack under the rear axle between
the spring anchor and the shock
absorber bracket.
If you have added a snow plow
to the front of your vehicle, lower
the snow plow fully before
raising the vehicle.
Make sure that the jack head is
positioned so that the rear axle
is resting securely between the
grooves that are on the
jack head.
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.
WARNING
Raising your vehicle with the jack
improperly positioned can
damage the vehicle and even
make the vehicle fall. To help
avoid personal injury and vehicle
damage, be sure to fit the jack lift
head into the proper location
before raising the vehicle.
I n f o r ma t i o n P r o v i d e d b y :
Vehicle Care
6. Turn the wheel wrench
clockwise to raise the vehicle.
Raise the vehicle far enough off
the ground so there is enough
room for the spare tire to fit
under the wheel well.
7. Remove all the wheel nuts and
take off the flat tire.
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