GMC 2005 Sierra 1500 Pickup Owner's Manual page 493

Jacking Locations
A. Front Location (Two-Wheel-Drive 1500 Series)
B. Front Location (All Other Series)
C. Rear Location (All Series)
3. Position the jack under the vehicle as shown. If the
flat tire is on the front of the vehicle (two-wheel-drive
1500 Series vehicles), position the jack under the
bracket attached to the vehicle's frame, behind
the flat tire. If the flat tire is on the front of the
vehicle (all other models), position the jack on the
frame behind the flat tire.
If the flat tire is on the rear, 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.
CAUTION:
{
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.
CAUTION:
{
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.
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