Hummer 2007 H3 - Manual (Page 265)

If you decide you can go down a hill safely, then
try to keep your vehicle headed straight down, and
use a low gear. This way, engine drag can help
your brakes and they will not have to do all
the work. Descend slowly, keeping your vehicle
under control at all times.
{ CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade.
This could cause loss of control and a
serious accident. Apply the brakes lightly
when descending a hill and use a low
gear to keep vehicle speed under control.
Q:
Are there some things I should not do
when driving down a hill?
A:
Yes! These are important because if you
ignore them you could lose control and
have a serious accident:
• When driving downhill, avoid turns that take
you across the incline of the hill. A hill that
is not too steep to drive down may be
too steep to drive across. You could roll over
if you do not drive straight down.
• Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work
and could overheat and fade.
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