Right Inline

The tech details behind the 2020 Silverado’s new 3.0L Duramax I-6 turbodiesel

- Bruce W. Smith

THE LAST TIME CHEVROLET OFFERED A STRAIGHT-SIX ENGINE WAS IN THE ’08 Trailblazer. That fuel-injected 4.2L gas-burner made 273 hp and 277 lb-ft of torque, with a combined EPA fuel economy rating of 16 mpg on the 4WD model. The inline-six was impressive, winning numerous awards for its innovations. But it’s nowhere near as impressive as the inline six Duramax diesel that makes its debut in the ’20 Chevrolet Silverado.

GM’s newest diesel, the third offering in the Duramax family, is 3.0 liters of high-tech innovation wrapped in an aluminum block and head. It delivers 277 ponies and 460 lb-ft of torque, coupled with fuel economy numbers expected to be in the 30s. The 3.0L Duramax has more horsepower than its Ford Power Stroke and Ram EcoDiesel rivals, and it flexes its torque muscle lower in the rpm band than both competitors.

From what we experienced in our first-drive of a Silverado with this engine, the inline-six Duramax, which makes more torque than the Silverado’s available 6.2L V-8 and is backed by the same 10-speed automatic as found in the Camaro ZL1, is a sweet package for those who want a nice balance of towing muscle and fuel economy in a 1⁄2-ton pickup. It’s quick, smooth, and quiet.

Clean-Sheet Design

Other than the name, the 3.0L inline-six has little in common with the 2.8L I-4 Duramax found in the Colorado/Canyon and the 6.6L V-8 Duramax under the hood of the 2500/3500HDs.

“It is a clean-sheet design from the air intake down to the engine mounts,” said John Barta, assistant chief engineer for the new Duramax. “Very, very few common things were used from the other Duramax engines. We’ve optimized everything in this engine’s design to fit into the new-generation Silverados while incorporating advanced combustion and emissions technologies to optimize performance and efficiency.”