GMC 2010 Sierra - Manual (Page 569)

Rear Position – 1500
Models
Rear Position – All Other
Models
5. If the flat tire is on the rear, for 1500 models
position the jack under the rear axle about 2 inches
(5 cm) inboard of the shock absorber bracket; 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.
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.
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