Chevrolet 2008 Silverado 1500 Pickup Owner's Manual page 334

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 the 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.
4-22
There some things not to do when driving down a hill.
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."
The brakes will have to do all the work and could
overheat and fade.
Your vehicle is much more likely to stall when going
uphill. But if it happens when going downhill:
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) and, while still braking, restart the
engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.