2001 GMC Sierra 1500 Pickup Owner's Manual - Page 118

CAUTION: Shifting the transfer case to NEUTRAL 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. See "Parking Brake" in the Index. NEUTRAL (N): Shift to this setting only when your vehicle needs to be towed. The ignition switch must be in RUN in order to shift the lever into NEUTRAL (N). See "Recreational Vehicle Towing" or "Towing your Vehicle" in the Index. 4-Wheel Low (4L0): This setting also engages your front axle and delivers extra torque. You may never need 4LO. It sends maximum power to all four wheels. You might choose 4LO if you are driving off-road in deep sand, deep mud, deep snow and climbing or descending steep hills. An indicator on the bezel near the lever shows you the transfer case settings: 2-Wheel High (2HI): This setting is used for driving in most street and highway situations. Your front axle is not engaged in two-wheel drive. This setting also provides the best fuel economy. 4-Wheel High (4HI): Use 4HI when you need extra traction, such as on snowy or icy roads or in most off-road situations. This setting also engages your front axle to help drive your vehicle. This is the best setting to use when plowing snow. 2-35