GMC 1994 Yukon Owner's Manual page 175

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 can't
control the vehicle as well or at all.
Because you will be on an unpaved surface, it's 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 isn't.
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" in the Index.)
Driving On Off-Road Hills
Off-road driving often takes you up, down, or across a hill. Driving safely
on hills requires good judgment and an understanding of what your vehicle
can and can't do. There are some hills that simply can't be driven, no matter
how well built the vehicle.
Approaching a Hill
When you approach a hill, you need to decide if it's one of those hills that's
just too steep to climb, descend, or cross. Steepness can be hard to judge.
On a very small hill, for example, there may be a smooth, constant incline
with only a small change in elevation where you can easily see all the way
to the top. On a large
hill,
the incline may get steeper as you near the top,
but you may not see
this
because the crest of the hill is hidden by bushes,
grass, or shrubs.
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