GMC Sierra 2000 Owner's Manual page 91

The front axle portion of the indicator diagram will light
up when you shift into four
axle engages.
Some delay between shifting and the indicator's lighting
is normal. If the front axle light does not go out
immediately after you shift out of four
have your dealer check your system.
-
wheel drive and the front
-
wheel drive,
An indicator near the lever shows you the transfer
case settings:
-
2 Wheel High (2H): This setting is for driving in most
street and highway situations. Your front axle is not
-
engaged in two wheel drive.
-
4 Wheel High (4H): This setting engages your front
axle to help drive your vehicle. Use 4H when you need
extra traction and in most off
CAUTION:
Shifting the transfer case to NEUTRAL (N) can
cause your vehicle to roll even if the transmission
is in PARK (P), or if you have a manual
transmission, even if you are in gear. You or
someone else could be seriously injured. Be sure
to set the parking brake before placing the
transfer case in NEUTRAL (N). See "Parking
Brake" in the Index.
-
road situations.
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