The new GMCSierra All Terrain HD is available on 2500HD and 3500HD double cab and crew cab models, and is offered with SLE or SLT trims – all with 4WD, including an electronically controlled transfer case. Also included is the Z71 Off Road package, with Rancho twin-tube shocks, hill descent control and a skid plate.  

Sierra HD’s 6.0L gasoline engine is standard and the Duramax turbo-diesel is available.

New and enhanced features introduced on the 2015 Sierra HD lineup include:

• CornerStep rear bumper, EZ Lift and Lower tailgate, standard locking tailgate, standard upper tie-downs and other features that make cargo handling easier.

• Standard StabiliTrak with Trailer Sway Control on all models.

• Integrated cruise control, auto grade braking and diesel exhaust braking, for greater driving control and reduced brake wear on grades.

• Enhanced cooling airflow, which enables the Duramax turbo diesel and 6.0L gasoline engine to better maintain full power, even under heavy loads and high ambient temperatures.

• New Duralife disc brake rotors that offer up to double the service life (late availability).

The 2015 Sierra HD also offers segment-exclusive safety features such as forward collision alert, lane departure warning with an active safety seat, and front and rear park assist. Head-curtain and seat-mounted side air bags are standard on 2500HD and available on 3500HD models.

All models are backed by GMC Pro Grade Protection, with two years of scheduled maintenance – including diesel exhaust fluid – a three-year/36,000-miles bumper-to-bumper warranty and a five-year/100,000-mile powertrain warranty. 

RELATED CONTENT: 

• Video: 2015 GMC Canyon to Offer Additional Safety Features