For the ultimate heavy-duty truck in GMCS lineup, there is the 2025 Sierra 3500HD, fresh off 2024s major update. This year, the Sierra 3500HD carries over with a series of small tweaks to its trim structure, with tech and safety features headlining the changes. The 2025 GMC Sierra 3500HD AT4 offers impressive towing capability, luxurious interior upgrades, and off-road-focused features, making it great for heavy-duty work and comfortMOTORTREND. Power through even the toughest terrain with the 6.6L Duramax Turbo Diesel engine paired with the Allison 10-speed automatic transmission. Take on the trail with Rancho shocks, skid plates, an Eaton automatic-locking rear differential and a max ground clearance of more than 10 inches along with a max front-approach angle of nearly 27 degrees on select models. Improved traction and control on gravel or mud with the traction Select System which allows you to shift smoothly among multiple settings including an off-road mode. The Auto-Trac transfer case with an active automatic 4WD setting seamlessly shifts between two- and four-wheel drive based on surface conditions and puts the power where you need it when you need it. Sierra HD AT4s rugged yet refined Jet Black interior with Kalahari accents offers premium materials and advanced technologies to help you take on the world in comfort and control. Sierra HD AT4 offers 10-way power front seats, heated and ventilated front leather seating surfaces and a leather wrapped heated steering wheel as standard features. This AT4 also features the Technology Package which picks up the rear camera mirror and Heads up display while the Preferred Package addsadaptive cruise control, a power sliding rear window, universal home remote and LED roof marker lamps.
