GMC 2004 Sierra 1500 Pickup Owner's Manual page 141

6. Simultaneously press and hold the 2HI and 4LO
buttons for 10 seconds. The red NEUTRAL light
will come on when the transfer case shift to
NEUTRAL is complete.
7. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, or 4LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. Release the parking brake.
6. You may start the engine and shift the transmission
to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
2-47