GMC adds off-road muscle to 2024 Sierra HD with AT4X trim

GMC is adding a top-end off-road AT4X trim to the 2024 heavy-duty Sierra pickup starting this fall.

The AT4X trim already is offered on the Sierra light-duty full-size pickup and the Canyon midsize pickup. It will debut on the freshened 2024 Sierra HD with a 1.5-inch suspension lift installed at the factory, along with Multimatic DSSV dampers, a rear e-locking differential, 35-inch tires, a larger steel transfer skid plate and front aluminum skid plate, and unique front upper and lower control arms and steering knuckles, GMC said.

"GMC's AT4X trim, which will be available across the entire GMC truck lineup, offers customers more premium choices when it comes to 'do-it-all' capabilities," Duncan Aldred, global vice president of Buick-GMC, said in a statement. "Each model delivers unique strengths, with the all-new Sierra HD AT4X taking it to the max, giving our customers the most luxurious and most off-road capable HD we've ever offered."

The Sierra HD AT4X comes with available trailering assistance technologies, including transparent trailer view for both gooseneck and fifth wheel trailering, trailer side blind zone alert and adaptive cruise control with trailering. As many as 14 available camera angles cover everything from the hitch view to the rear side view with a trailer length indicator. It provides up to 18,500 pounds of available trailering capacity, GMC said.

The interior of the Sierra HD AT4X is equipped with massaging front seats, while all seats are wrapped in full-grain leather. It comes with a 12-speaker premium Bose audio system, a 13.4-inch diagonal infotainment touchscreen, a 12.3-inch diagonal driver information center and a 15-inch diagonal head-up display.

In addition, GMC teamed up with American Expedition Vehicles, an off-road aftermarket equipment manufacturer, on a Sierra HD AT4X AEV edition. The AEV version will offer 18-inch wheels, stamped-steel bumpers, front winch capability, heavy-duty steel skid plates and distinct exterior badges.

The Sierra HD AT4X comes standard with a 6.6-litre gasoline engine with 401 hp and 464 pound-feet of torque. A 6.6-litre Duramax turbo-diesel engine is available with 470 hp and 975 pound-feet of torque. Both are mated to a 10-speed automatic transmission.

Pricing will be released at a later date.