GMC 1996 Sonoma Owner's Manual page 65

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 (1) 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.
Mr ual Transmission
5-Speed
1
This is your shift
pattern.
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