Manual Transmission Operation - GMC Sierra 3500HD 2001 Owner's Manual

FIRST (1): This position gives you even more power,
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
selector lever is put in FIRST (1) while the vehicle is
moving forward, the transmission won't shift into first
gear until the vehicle is going slowly enough.
NOTICE:
If your rear wheels can't rotate, don't try to
drive. This might happen if you were stuck in
very deep sand or mud or were up against a solid
object. You could damage your transmission.
Also, if you stop when going uphill, don't hold
your vehicle there with only the accelerator
pedal. This could overheat and damage the
transmission. Use your brakes or shift into
PARK (P) to hold your vehicle in position on
a hill.

Manual Transmission Operation

5-Speed
FIRST (1) is intended only for heavy loads and is not
recommended for normal driving.
During the first 500 miles (805 km) of vehicle use, start
your vehicle moving in FIRST (1). This allows clutch
-
components to break in properly.
Here's how to operate
your transmission.
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