The 2020 Silverado HD is available with two rip-roaring engines: the all-new 6.6-liter V8 gas engine or the optional Duramax® 6.6-liter turbo-diesel. The 6.6-liter V8 supplies 401 horsepower and 464 lb-ft of torque, while the Duramax® produces 445 horsepower and 910 lb-ft of torque. The 6.6-liter V8 is paired with a smooth six-speed automatic transmission. By contrast, the Duramax® comes with an all-new Allison 10-speed automatic transmission for smoother gear shifting. With either powertrain option, you will have more than enough raw force to tackle just about any job.