2005 GMC Sierra 1500 Pickup Owner's Manual - Page 135

You can choose among three driving settings: Recommended Transfer Case Settings Driving Conditions Normal Severe Extreme Vehicle in Tow* Transfer Case Settings 2HI YES YES YES YES 4HI 4LO N When operating in 4LO, the gear ratio is extra deep when compared to 4HI. The transmission gear shift feel will be exaggerated. Indicator lights in the switches show you which setting you are in. The indicator lights will come on briefly when you turn on the ignition and the last chosen setting will stay on. If the lights do not come on, you should take your vehicle in for service. An indicator light will flash while shifting. It will remain illuminated when the shift is completed. If for some reason the transfer cannot make a requested shift, it will return to the last chosen setting. *See Recreational Vehicle Towing on page 4-62 or Towing Your Vehicle on page 4-62 for further information. {CAUTION: Shifting the transfer case to NEUTRAL 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. See Parking Brake on page 2-48. NEUTRAL: Shift the vehicle's transfer case to NEUTRAL only when towing your vehicle. See Recreational Vehicle Towing on page 4-62 or Towing Your Vehicle on page 4-62 for more information. 2-45 h (2HI): This setting is for driving in most street and highway situations. Your front axle is not engaged in two-wheel drive. This setting engages your front axle to help drive your vehicle. Use 4HI when you need extra traction, such as on snowy or icy roads, or in most off-road situations. G (4HI): g (4LO): This setting also engages your front axle to give you extra traction. You may never need 4LO. It sends the maximum power to all four wheels. You might choose 4LO if you were driving off-road in sand, mud or deep snow and climbing or descending steep hills.