2004 GMC Sierra 1500 Pickup Owner's Manual - Page 138

Electronic Transfer Case If your four-wheel-drive vehicle has the electronic transfer case, the transfer case switches are located to the left of the instrument panel cluster. Use these switches to shift into and out of four-wheel drive. You can choose among three driving settings: Recommended Transfer Case Settings Transfer Case Settings Driving Conditions Normal Severe Extreme Vehicle in Tow* 2HI YES YES YES YES 4HI 4LO N *See Recreational Vehicle Towing on page 4-54 or Towing Your Vehicle on page 4-53 for further information. 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): 2-44