September 27, 2013 – The 2015 GMC Sierra HDs arrive in the first quarter of next year, including 2500HD and 3500HD models, as well as the Denali HD, which sports an exclusive package of design and upscale interior amenities.

The new interior is designed to help drivers and passengers with easier-to-reach, more intuitively located controls, more storage compartments, more plug-ins for electronic devices, and the latest-generation GMC IntelliLink infotainment system (with an 8-in.-diagonal colour touchscreen.

Additional new and enhanced features for the 2015 Sierra HD lineup include CornerStep rear bumper, EZ Lift-and-Lower tailgate, standard upper tie-downs and more to make cargo-handling easier. The trucks come standard with StabiliTrak with Trailer Sway Control on all models, including the dually, and integrated cruise control, auto grade braking and diesel exhaust braking (diesel models) for greater driving control and reduced brake wear on grades.

The Sierra Denali HD features a signature chrome grille, unique interior decorative trim, a polished stainless steel exhaust outlet (gas models) and body-colour front and rear bumpers. Complementing the soft-touch instrument panel trim and aluminum trim are Denali-specific interior details, including script on the door sills and embossed into the front seats.

LED cargo box lighting is standard on SLE, SLT and Denali models. Two LED lights are mounted under the box side rails and are activated by a switch on the instrument panel, providing a light source when a tonneau cover is installed or a flashlight isn’t available.

A Vortec 6.0L gas V-8 with variable valve timing is matched with the Hydra-Matic 6L90 six-speed automatic transmission as the standard powertrain across the Sierra HD model range. This combination is engineered to deliver performance and efficiency, especially at low rpms, says GM. It is rated at 360 hp and 380 lb-ft of torque in 2500HD models and 322 hp and 380 lb-ft in 3500HD.

The 6.0L engine is also available in a bi-fuel model that features hardened valves and valve seats that enables it to run on compressed natural gas or gasoline. The CNG fuel system is installed by a GM supplier, and completed vehicles are delivered directly to the customer. The Duramax 6.6L diesel and Allison 1000 six-speed automatic transmission powertrain combination is available on all 2500HD and 3500HD models.