GMC 1996 Sierra Owner's Manual page 87

Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2H1, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N). The preferred method
for shifting out of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4HI
switch. You must wait for the 4HI indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4HI switch is pressed when your vehicle is in
gear and/or moving, the 4HI indicator light will flash for
30 seconds but not complete the shift unless the vehicle
is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N).
Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking brake
pedal with your left foot.
If the ignition is on, the brake system warning light will
come on.
To release the parking brake, hold the regular brake
pedal down.
lull the lever, located
1st above the parking
rake pedal, marked
;RAKE RELEASE.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
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