Leaked Specs Reveal Power, Fuel Economy of GM's Diesel Inline-six

Steph Willems
by Steph Willems

The EPA hasn’t officially rated the 3.0-liter inline-six diesel bound for the 2019 Chevrolet Silverado and GMC Sierra, nor has the automaker released power specs for this Flint-built light truck engine.

Thankfully, someone took photos of GM Canada’s dealer site and flung them to the internet.

Published by TFL Truck, shots of a page detailing the 2019 Sierra show the new Duramax engine generating 282 horsepower and 450 lb-ft of torque — an output that beats Ford’s 3.0-liter PowerStroke V6 by 32 hp and 10 lb-ft of twist. Once confirmed, this information won’t have any of the ferociously competitive denizens of Dearborn smiling.

General Motors is the last of the Detroit Three to offer a diesel in its full-size pickups. FCA began the trend in 2014 with its 3.0-liter EcoDiesel V6, then rated at 240 hp and 420 lb-ft. An improved motor is promised for 2019, so the power race is still on.

As for fuel economy, it seems Ford still holds some bragging rights. The dealer site shows the Duramax engine returning 28 mpg on the highway, less than the maximum 30 mpg offered by Ford. GM, of course, opted against going the all-aluminum route when constructing the body of its new truck.

During the launch of the 2019 Silverado, Chevy brass boasted that their new diesel would “outperform” the Ford engine, and it appears they were correct.

Mated to a 10-speed automatic transmission, the GM 3.0-liter is said to be offered on SLE, Elevation, SLT, AT4 and Denali trim levels, with a maximum towing capacity of 7,800 pounds. It joins another new engine — a 2.7-liter turbocharged four-cylinder— and returning 4.3-, 5.3-, and 6.2-liter engines in the Silverado and Sierra range. The latter two engines now boast GM’s Dynamic Fuel Management, which deactivates up to seven cylinders at any given time for improved fuel economy.

[Image: Steph Willems/TTAC]

Steph Willems
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  • Iamwho2k Iamwho2k on Oct 05, 2018

    That Sierra is ghastly. Nothing on that front end is cohesive. Four different guys must have been assigned to the project --and they worked in different studios.

    • Road_pizza Road_pizza on Oct 05, 2018

      This. And they were not allowed any contact with one another.

  • Aron9000 Aron9000 on Oct 09, 2018

    I will give GM some credit, at least they stack the cylinders in the right order(inline six instead of V6). Still though, diesel, at least how its done here in the United States makes no sense except for big trucks where you actually need the torque. The running costs on "heavy duty" diesel pickups is quite ridiculous, seems like all 3 of them have problems with the emissions equipment and other various bs things after they go off warranty. And I'm not talking $500-1000 problems, try more like $3k, $5k or more to fix things like injectors, dpf filters, urea systems, its just outrageous what it costs to service these trucks. Add into the fact that diesel is $0.60 cents more expensive than regular 87 where I live, you save big money buying a gas engine over the long haul. Add into the fact that this is probably going to be an expensive option only on upper trim levels, I just don't see the value.

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