Powertrain options, as with "lesser" Silverado HD models, include the 6.0-liter V8 with 360 horsepower and 380 pound-feet of torque, a version of the same equipped to run flexibly on CNG, or the 6.6-liter Duramax turbodiesel with 397 hp and a mind-blowing 765 lb-ft of earth-turning torque
