Big jobs require big engines.
Duramax V-8 barely works to move recreational vehicle in bed.
David Kimble cutaway of new 6.6L Duramax V-8.
Tom Murphy
Sierra Denali 2500 logs 9.5 mpg while towing 10,000 lbs. through steep terrain.
Tom Murphy
Exhaust braking vitally important on downhill grades.
Tom Murphy
Exhaust brake switch on instrument panel.
Tom Murphy
Driver notified when exhaust brake turned on or off.
GMC Sierra Denali HD interior comfortable, upscale.
Tom Murphy
Duramax packed into engine bay of Sierra Denali HD.
Tom Murphy
Driver can select rearward camera view as towing aid.
Tom Murphy
Camera shows driver-side rear view.
New Duramax V-8 manufactured at GM plant in Moraine, OH, while truck hails from Flint, MI.