GMC 1993 Suburban Owner's Manual page 197

Turning or driving across steep hills can be dangerous. You could
lose traction, slide sideways, and possibly roll over. You could be
seriously injured or killed. When driving up hills, always try to go
straight up.
8
Ease up on your speed as you approach the top of the hill.
0
Attach a flag to the vehicle to make you more visible to approaching
e
Sound the horn as you approach the top of hill to let opposing traffic
traffic on trails or hills.
know you're there.
Use your headlights even during the day. They make you more visible to
oncoming traffic.
Driving to the top (crest) of a hill at full speed can cause an
accident. There could be a drop-off, embankment, cliff, or even
another vehicle. You could be seriously injured or killed. As you near
the top of a hill, slow down and stay alert.
8: What should I do if my vehicle stalls, or is about to
stall,
and I can't
make it up
the
hill?
A: If this happens, there are some things you should do, and there are some
things you must not do. First, here's what you should do:
Q
Push the brake pedal to stop the vehicle and keep it from rolling
backwards. Also, apply the parking brake.
Q
If your engine is still running, shift the transmission into reverse, release
the parking brake, and slowly back down the hill in reverse.
8
I f your engine has stopped running, you'll need to restart it. With the
brake pedal depressed and the parking brake still applied, shift the
transmission to
P
(Park) (or, shift to M (Neutral) if your vehicle has
a
manual transmission) and restart the engine. Then, shift to reverse,
release the parking brake, and slowly back down the hill in reverse.
Q
As you are backing down the hill, put your left hand on the steering
wheel at the 12 o'clock position. This way, you'll be able
to
tell i f your
wheels are straight or turned to the left or right as you back down.
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