Hummer 2004 H2 Owner's Manual page 399

X= 28.5 inches (72.0 cm)
Rear Position
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.
Rear Flat Tire: Place the
jack under the curved rear
axle pad. Make sure
the jack head is positioned
so that the rear axle
pad is resting securely on
the jack head.
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