2005 GMC Sierra 1500 Pickup Owner's Manual - Page 128

A 4WD indicator light will illuminate when you shift into four-wheel drive and the front axle engages. See Four-Wheel-Drive Light on page 3-48. An indicator light 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. Some delay between shifting and the indicator's lighting is normal. Recommended Transfer Case Settings Transfer Case Settings Driving Conditions Normal Severe Extreme Vehicle in Tow* 2HI YES YES YES YES 4HI 4LO N {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 on page 2-48. *See Recreational Vehicle Towing on page 4-62 or Towing Your Vehicle on page 4-62 for further information. 2-38