GMC 2007 Envoy - Manual (Page 324)

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 cannot do. There are some hills
that simply cannot be driven, no matter how
well built the vehicle.
{ CAUTION:
Many hills are simply too steep for any
vehicle. If you drive up them, you will stall.
If you drive down them, you cannot control
your speed. If you drive across them, you
will roll over. You could be seriously
injured or killed. If you have any doubt
about the steepness, do not drive the hill.
Approaching a Hill
When you approach a hill, you need to decide if it
is one of those hills that is 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.
Here are some other things to consider as
you approach a hill.
• Is there a constant incline, or does the hill get
sharply steeper in places?
• Is there good traction on the hillside, or will
the surface cause tire slipping?
• Is there a straight path up or down the hill so
you will not have to make turning maneuvers?
• Are there obstructions on the hill that can
block your path, such as boulders, trees, logs,
or ruts?
• What is beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out
and walk the hill if you do not know. It is the
smart way to find out.
• Is the hill simply too rough? Steep hills often
have ruts, gullies, troughs, and exposed
rocks because they are more susceptible to
the effects of erosion.
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