1999 GMC Suburban Owner's Manual - Page 90

yellowblue The transfer case shift lever is on the floor to the right of the driver. Use this lever to shift into and out of four-wheel drive. 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-road situations. CAUTION: Shifting the transfer case to NEUTRAL (N) can cause your vehicle to roll even if the transmission is in PARK (P). 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. The front axle portion of the indicator diagram will light up when you shift into four-wheel drive and the front 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-wheel drive, have your dealer check your system. An indicator near the lever shows you the transfer case settings: 2-20