GMC 2012 Sierra Owner's Manual page 467

Front Position - All Other Models
Position the jack under the
vehicle, as shown. If the flat tire
is on the front of the vehicle (all
other models), position the jack
on the frame behind the flat tire.
Rear Position 1500 Models
5. If the flat tire is on the rear, for
1500 models position the jack
under the rear axle about 5 cm
(2 in) inboard of the shock
absorber bracket.
I n f o r ma t i o n P r o v i d e d b y :
Vehicle Care
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 a snow plow has been added
to the front of the vehicle, lower
the snow plow fully before
raising the vehicle.
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