GMC 2001 Sierra 1500 Pickup Owner's Manual page 249

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 won't 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.
D
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that's not too
steep to drive down may be too steep to drive across.
You could roll over if you don't drive straight down.
D
Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal
pressed down in a manual shift. This is called
-
"free wheeling." Your brakes will have to do
all the work and could overheat and fade.
Q:
Am I likely to stall when going downhill?
A:
It's much more likely to happen going uphill.
But if it happens going downhill, here's what to do.
D
Stop your vehicle by applying the regular brakes.
Apply the parking brake.
D
Shift to PARK (P) (or to NEUTRAL (N) with the
manual transmission) and, while still braking, restart
the engine.
D
Shift back to a low gear, release the parking brake,
and drive straight down.
D
If the engine won't start, get out and get help.
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