Hummer 2008 H3 Owner's Manual page 343

5. Assemble the jack and tools as follows:
Front Position
Front Tire Flat: If the flat tire is on a front tire of
the vehicle, you will need to use the jack handle and
both jack handle extensions. Attach the wheel
wrench to the jack handle extensions. Attach the
jack handle to the jack. From the front of the vehicle
position the jack on the front lower control arm
along the bar that runs front to back. 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.
Rear Positions
Refer to the graphic above to locate the placement
of the jack if the flat tire is on the rear of the
vehicle.
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