Hummer 2006 H3 Owner's Manual page 345

Rear Tire Flat: You will need to use the jack
handle and both jack handle extensions. Attach the
wheel wrench to the jack extensions. Attach the
jack handle to the jack. Align the jack under the rear
axle. 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
clear the ground.
5. Turn the wheel wrench clockwise to raise the jack
head to the lifting point.
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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