2024 Gmc Sierra 2500hd Denali Ultimate Speed. Gmc is adding a denali ultimate trim to the top of the. 2024 gmc sierra 2500hd and 3500hd pickup trucks equipped with the denali ultimate trim are the only truck in gmc’s lineup that come standard with the 6.6l l5p duramax diesel engine, producing 470.

2024 gmc sierra 2500hd and 3500hd pickup trucks equipped with the denali ultimate trim are the only truck in gmc’s lineup that come standard with the 6.6l l5p duramax diesel engine, producing 470. Standard 13.4 diagonal center touch.