Hummer H2 2009 Owner's Manual page 435

CAUTION: (Continued)
4. Turn off the engine and do not restart while
the vehicle is raised.
5. Do not allow passengers to remain in the
vehicle.
To be even more certain the vehicle will not move,
you can put blocks at the front and rear of the tire
farthest away from the one being changed. That
would be the tire on the other side, at the opposite
end of the vehicle.
When the vehicle has a flat tire (B), use the following
example as a guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains how to use the jack
and change a tire.
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