What Type Of Vehicles Are Powered By The Cummins X15 Engine?

Clessie Cummins founded the Cummins Engine Company over 100 years ago, and the company has been regularly churning out big-capacity and big-power diesel engines since then. While the largest Cummins engines are reserved for industrial uses only, a number of pickup trucks also use Cummins diesel engines, most notably Dodge and Ram trucks. Ford also used to sell Cummins-powered Super Duty trucks, before developing its own Power Stroke diesel engine.

We'll be placing the more civilian engines and applications aside for the moment and zero in on the X15 Cummins diesel engine. You won't find this powerplant lurking beneath the hood of a Super Duty or Ram, though, as it's a 14.9-liter inline-six engine designed to power vehicles that would tower over your typical full-size pickup truck.

The exact power output of the X15 differs depending on the desired specification and application of the X15 engine, but Cummins states that the mighty inline-six dishes out between 450 and 675 hp and anywhere between 1,600 and 2,050 lb-ft of torque. To place those figures into perspective, it's not far off doubling the torque output of the 6.7-liter Cummins-powered 2025 Ram 3500HD truck.

According to Cummins, the main applications for the X15 engine are mining, rail, construction, and agriculture, and the engine itself is available throughout most of the world. Cummins claims that the X15 is one of the most reliable and powerful class 8 truck engines available, with the X15 Efficiency Series being the tool of choice for long-haul truck drivers in North America. Class 8 trucks are typically referred to as semi-trucks, but they are more specifically trucks with a gross vehicle weight rating (GVWR) that exceeds 33,000 pounds.

For those who want more than 500 hp from their X15 engine, though, the Performance Series is the way to go. Conversely, Cummins advises that users who require continual access to peak horsepower are better off opting for the X15 Productivity Series. This wide range of options demonstrates just how useful and versatile the X15 Cummins engine really is.

Cummins only manufactures the engine, with a number of truck manufacturers selling brand-new models with the X15 supplied as standard. As of 2022, these included companies such as Freightliner, International, Peterbilt, Volvo, and Kenworth — including the soon-to-be-discontinued Kenworth W900.