GMC 1996 Suburban Owner's Manual page 196

Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system and
transmission. These par@ can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
A
CAUTION:
If you don't shift down, your brakes could
get
so
hot that they wouldn't work well. You
would then have poor braking or even none going
down a hill. You could crash. Shift down to let
your
engine assist your brakes on a steep
downhill slope.
Coasting downhill in NEUTRAL (N)
or
with the
ignition off is dangerous. Your brakes will have to
do all the work of slowing down. They could get so
hot that they wouldn't work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.
_ ?
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Don't swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car or m accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert to these and take appropriate action.
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