Hummer 2004 H2 - Manual (Page 256)

Crossing Obstacles
Approach Angle — a Key to Mobility. If you encounter a
large dip in the terrain, do not enter straight on; enter
at an angle — 15° minimum approach (A), 75° maximum
approach angle (B). For very large dips, ditches or
small washes, coast in, using the engine as a brake
(transmission and transfer case lowest gears). Then, use
the low ranges in the transmission and transfer case
to power out.
Roll Your Tires Over Large
Rocks. Do not straddle
large rocks; drive
over them, letting the tire
envelop the rock. The
tread of the tire is thicker
and tougher than the
sidewall of the tire and is
more resilient to impact
than underbody
components.
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