GMC 1993 Suburban Owner's Manual page 198

I
Here are some things you must not do if you stall, or are about to stall,
when going up a hill.
8
Never attempt to prevent a stall by shifting into N (Neutral) (or
depressing the clutch, if you have a manual transmission) to "rev-up" the
engine and regain forward momentum. This won't work. Your vehicle will
roll backwards very quickly and you could go out
of
control.
Instead, apply the regular brake to stop the vehicle. Then apply the parking
brake. Shift into reverse, release the parking brake, and slowly back down.
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Never attempt to turn around i f you are about to stall when going up a
hill. If the hill is steep enough
to stall your vehicle, it's steep enough to
cause you to roll over i f you turn around. If you can't make it up the
hill, you must back down the hill.
Q: Suppose, after stalling, I
try to
back down the hill and decide I I just
can't do it. What should I do?
A: Set the parking brake, put your transmission in P (Park) (or
the
manual
transmission in first gear), and turn off the engine. Leave the vehicle and go
get some help. Exit on the uphill side and stay clear of the path the vehicle
would take if it rolled downhill. Do not shift the transfer case to M (Neutral)
when you leave the vehicle. Leave it in some gear.
Shifting the transfer case
to W (Neutral) can cause
your
vehicle to
roll even if the transmission
is
in P (Park) (or, if you have the
manual transmission, even if you're in gear). This is because ttie 5\1
(Neutral) position on the transfer case overrides the transmission. If
you are going to leave your vehicle, set the parking brake and shift
the transmission to P (Park) (or, put your manual transmission in first
gear). But do not shift the transfer case to the N (Neutral) position.
Leave the transfer case in the 2 Wheel, 4 High or 4 Low position.
Ddwing DownhiBB
When off-roading takes you downhill, you'll want to consider a number of
things:
e
How steep is the downhill? Will I be able to maintain vehicle control?
e
What's the surface like? Smooth? Rough? Slippery? Hard-packed
dirt?
8
Are there hidden surface obstacles? Ruts? Logs? Boulders?
Gravel?
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