2025 Gmc Sierra 2025 Duramax. Denali goes ultimate, at4x joins the ranks. The 2025 gmc sierra 2500hd denali ultimate carries its 8,346 pounds of mass to 60 mph in a shockingly quick 6.5 seconds.

2025 gmc sierra 2500 and 3500 hd first look: We get hands on with gm’s 2025 heavy duty pickups, comparing the gmc sierra 2500 hd denali ultimate and the chevy silverado 2500 hd zr2.