Hummer 2008 H2 - Manual (Page 425)

4. Turn the wheel wrench counterclockwise to loosen
the wheel nuts. Do not remove them yet.
Now jack the vehicle up.
5. Assemble the jack and tools:
Front Flat Tire: Attach the jack handle with the
hook end connected to the hole on the jack. Slide
the wheel wrench onto the jack handle extension.
Rear Flat Tire: Assemble the jack together with the
jack handle and the jack handle extensions.
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