The Sierra HD Denali Ultimate has a unique grille, dark chrome badging and an interior filled with full-grain leather and open-pore Paldao wood accents. It comes with massaging front seats, a microsuede headliner, a 12-speaker Bose Premium system, a 15-inch multicolor head-up display and a power sunroof.
The AT4X is a higher-end version of the AT4 trim designed for off-roading. AT4, which GMC introduced in 2019, accounts for 27 per cent of Sierra HD sales and attracts a younger, more affluent buyer, Aldred said.
GMC will reveal pricing closer to the start of output.
The 2024 Sierra HD equipped with a 6.6-litre Duramax turbodiesel V-8 produces 470 hp and 975 pound-feet of torque, up from 445 hp and 910 pound-feet of torque. Maximum towing capacity on the Sierra 2500 is 22,500 pounds, a 4,000-pound increase.
The available ProGrade trailering system providing up to 14 camera views has the most available trailering assistance technologies in the Sierra HD’s class, GMC said, and a 13.4-inch diagonal tablet-style infotainment touch screen is the largest offered in the class.