Chevrolet 2008 Silverado 1500 Pickup Owner's Manual page 509

Rear Position – All Models
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.
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.
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.
5. 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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