GMC Sierra 2000 Owner's Manual page 86

CAUTION:
Shifting out of PARK (P) or NEUTRAL (N) while
your engine is "racing" (running at high speed) is
dangerous. Unless your foot is firmly on the
brake pedal, your vehicle could move very
rapidly. You could lose control and hit people or
objects. Don't shift out of PARK (P) or
NEUTRAL (N) while your engine is racing.
NOTICE:
Damage to your transmission caused by shifting
out of PARK (P) or NEUTRAL (N) with the
engine racing isn't covered by your warranty.
2-18
AUTOMATIC OVERDRIVE (
normal driving. If you need more power for passing,
and you're:
D
Going less than about 35 mph (56 km/h), push your
accelerator pedal about halfway down.
D
Going about 35 mph (56 km/h) or more, push the
accelerator all the way down.
You'll shift down to the next gear and have more power.
AUTOMATIC OVERDRIVE (
towing a trailer, carrying a heavy load, driving on steep
-
hills or for off road driving. You may want to shift the
transmission to THIRD (3) or, if necessary, a lower gear
selection if the transmission shifts too often.
THIRD (3): This position is also used for normal
driving, however it offers more power and lower fuel
economy than AUTOMATIC OVERDRIVE (
SECOND (2): This position gives you more power, but
lower fuel economy. You can use SECOND (2) on hills.
It can help control your speed as you go down steep
mountain roads, but then you would also want to use
your brakes off and on.
If you manually select SECOND (2), the transmission
will drive in second gear. You may use this feature for
reducing torque to the rear wheels when you are trying to
start your vehicle from a stop on slippery road surfaces.
B
): This position is for
B
) can be used when
B
).