The Most. And The Best
With 397 horsepower and an astounding 765 pounds-feet of torque, Sierra HD's re-engineered Duramax diesel engine generates outstanding power and torque, providing more capability than ever before†. And that's only part of the story. Thanks to its advanced, Diesel Emission Fluid (DEF) technology, it uses less fuel.† And with improvements to its internal lubrication system, it's even engineered to last longer than its highly respected predecessor.