Arming the System
To arm the system, do one of the following:
○ Press 
on the RKE transmitter.
○ Lock the vehicle using the key in the driver door.
The alarm automatically arms after about 30 seconds. The security light, located on the instrument panel, flashes.
Press 
on the RKE transmitter to
open the liftgate without setting off the alarm. The system rearms when the liftgate
is closed.
See also:
Powertrain details
The GMC Sierra All Terrain HD concept is propelled by the new, production
6.6L Duramax turbo-diesel V-8 and Allison 1000 six-speed automatic transmission
powertrain combination offered in the 2011 ...
Roadside Assistance Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801
As the owner of a new GMC, you are automatically enrolled in the Roadside Assistance program.
...
Driving in Mud, Sand, Snow, or Ice
Use a low gear when driving in mud – the deeper the mud, the lower the gear. Keep the vehicle moving to avoid getting stuck.
Traction changes when driving on sand. On loose sand, such as on beaches ...