Hummer 2007 H3 - Manual (Page 258)

When you drive over bumps, rocks, or other
obstacles, your wheels can leave the ground.
If this happens, even with one or two wheels, you
cannot control the vehicle as well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
In a way, off-road driving requires a different kind
of alertness from driving on paved roads and
highways. There are no road signs, posted speed
limits, or signal lights. You have to use your
own good judgment about what is safe and
what is not.
Drinking and driving can be very dangerous on
any road. And this is certainly true for off-road
driving. At the very time you need special
alertness and driving skills, your reflexes,
perceptions, and judgment can be affected by
even a small amount of alcohol. You could have
a serious — or even fatal — accident if you
drink and drive or ride with a driver who has been
drinking. See Drunken Driving on page 235.
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 degrees
minimum approach (A), 75 degrees 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.
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