General Motors' Duramax engine family is one of the three leading names in diesel engines ... in the same heavy-duty Chevy Silverado and GMC Sierra 2500 HD and 3500 HD trucks its predecessor ...

the GMC Sierra and Chevrolet Silverado. Both brands designate their heavy-duty models as 2500 and 3500, and it's within that range you'll find options for the 6.6-liter Duramax diesel engine.

A Mega Cab is exclusive to Ram 2500 and 3500 trucks and increases the amount of interior space for passengers and cargo compared to a crew cab but comes with only one bed length. As the names ...