GMC 2003 Savana Van Owner's Manual page 220

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.
could be something in your lane, like a stalled car or
an accident.
0
As you go over the top of a hill, be alert. There
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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