What Makes The Duramax 3.0 Diesel Engine So Good

The Duramax diesel engines have been a staple for Chevrolet and GMC trucks since the beginning of the 21st Century. It began with a 6.6L V8 that General Motors could place under the hood of its heaviest duty trucks, granting a mixture of power and fuel efficiency. After a number of years, GM aimed to make smaller Duramax diesel engines for its vehicles, which began with inline-four engines in displacements of 2.5L and 2.8L, though they discontinued these engines after seven years. 

For the 2019 model year, GM introduced another Duramax that remains an option for Chevrolet and GM's signature trucks — the Silverado and Sierra, respectively — and other larger vehicles in their arsenals, such as the Chevrolet Tahoe or GMC Yukon. Rather than mirror the 6.6L V8, this iteration of a Duramax engine takes its cue from the smaller model and employs an inline-six engine design. 

This Duramax diesel engine features a bore of 3.3 inches, and a stroke of 3.54 inches, resulting in a slight tick up form the inline-four Duramax for 3.0L of displacement. This is the same amount of displacement you will find in diesel-powered engines from other companies like the Ford Power Stroke and Ram EcoDiesel. That said, the GM Duramax is able to outpace both when it comes to power and towing capacity. However, this wasn't always true about the Duramax. Even with it being available for just a few years, GM has already been making improvements to make this the diesel engine of choice for light trucks and SUVs.

Up until fairly recently, the maximum horsepower you could get with the 3.0L Duramax inline-six engine was 277 horsepower and 460 pound-feet of torque. While that does either outshine or remain competitive with the aforementioned Ford Super Duty and Ram EcoDiesel engines, the 2023 model year saw quite the increase. Now, these Duramax engines are able to max out at 305 horsepower and 495 pound-feet of torque. 

GM has also been able to massively increase the engine's towing capabilities, increasing its maximum weight from 9,500 pounds in a Chevrolet Silverado 1500 to a whopping 13,300 pounds. The one place this newest iteration took a tiny step back was in its highway mileage, though the combined mileage ultimately remained consistent, with an average of 26 mph for a 2WD model. From just about every metric, it stands as the powerhouse among diesel engines.

You won't be able to get this engine on base models of the Chevy Silverado 1500 or GMC Sierra 1500, but certain packages have the Duramax either standard or an option, such as the Silverado RST or Sierra AT4. These will tend to be packages intended to up performance, improve off-roading, or designed for hauling, where diesel fuel is more practical.

It should be noted that diesel engines have started drifting away as companies continue to favor investing in electric vehicle technology and hybrid drivetrains. For example, Ram ceased production on its EcoDiesel engine, so if you have your sights set on a truck of SUV with a diesel, it's a good thing that GM continues to invest in and improve its Duramax. Considering it can power two of the 10 best-selling vehicles in the United States, it behooves GM to keep it up for now.