Hummer 2006 H3 Owner's Manual page 344

4. 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 extension. Attach the jack
handle to the jack. 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.
5-78
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.