2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 29

AUTO (Automatic Four-Wheel Drive): This setting is ideal for use when road surface traction conditions are variable. 4 m (Four-Wheel High): Use the Four-Wheel-Drive High position when extra traction is needed, such as on snowy or icy roads or in most off-road situations. N (Neutral): Shift the transfer case to Neutral only when towing the vehicle. See Recreational Vehicle Towing on page 5‑49 or Towing a Trailer on page 5‑55. 4 n (Four-Wheel-Drive Low): This setting sends maximum power to all four wheels. You might choose Four-Wheel-Drive Low if you are driving off-road in deep sand, deep mud, deep snow, and while climbing or descending steep hills. See Four-Wheel Drive on page 3‑39. Vehicle Features Radio(s) Radio with CD, DVD, and USB Port O: Press to turn the system on and off. Turn to increase or decrease the volume. BAND: Press to choose between FM, AM, or XM™, if equipped. 1-23