Hummer 2006 H3 - Manual (Page 246)

If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See Off-Road
Driving on page 4-17 for information about driving
off-road.
• Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system,
and transmission. These parts can work hard
on mountain roads.
{ CAUTION:
If you do not shift down, your brakes could
get so hot that they would not 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.
{ CAUTION:
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 would not
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 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.
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