2024 Gmc Denali Hd Duramax Diesel. Gmc is adding a denali ultimate trim to the top of the. Sierra hd denali’s standard 6.6l.
Denali ultimate hd trucks feature a standard powertrain upgrade, receiving the powerful 6.6l v8 l5p duramax diesel engine. For hauling, the denali ultimate comes standard with the 6.6l duramax diesel engine.