Kenworth Announces Cummins X15N Natural Gas Engine Production
The Cummins X15N natural gas truck engine produces between 400-500 hp with up to 1,850 lb.-ft. of torque and is compatible with Eaton Cummins Endurant and Allison Transmissions.

Kenworth T680s with the Cummins X15N natural gas engine will be available later this year.
Photo: Kenworth
Kenworth announced it will begin production of Kenworth T680 and T880 models specified with the new Cummins X15N natural gas engine in the third quarter of 2024.
Cummins said the X15N, powered by Compressed Natural Gas (CNG), Renewable Natural Gas (RNG) or Liquified Natural Gas (LNG), is the industry’s first 15-liter natural gas engine that delivers diesel-like power, range, and performance. These features make it appealing for short, regional, and long-haul operations.
Immediate CARB Compliance
The X15N produces between 400-500 hp with up to 1,850 lb.-ft. of torque and is compatible with Eaton Cummins Endurant and Allison Transmissions.
Additionally, the Cummins X15N meets stringent EPA emission requirements and CARB 2024 Low NOx standards. It also offers up to a 10% improvement in fuel economy over Cummins’ 12-liter natural gas engine with similar rating and duty cycle.
Kenworth said it is the first major truck manufacturer to offer an engine that meets CARB’s NOx emission standards.
“We’re thrilled to soon begin production of Kenworth trucks with the Cummins X15N natural gas engine,” said Kevin Haygood, Kenworth assistant general manager for sales and marketing. “This new engine offering will be a great alternative solution for Kenworth customers seeking to reduce emissions in applications that require the power and performance they’re accustomed to with diesel engines.”
“We’re pleased to partner with Kenworth and Paccar to deliver the industry’s first trucks with this new 15-liter natural gas engine,” said José Samperio, Cummins vice president and general manager for North America. “The X15N delivers the performance, durability, and power required in a variety of heavy-duty and vocational applications and is an excellent alternative for fleets looking to significantly reduce their carbon footprint.”
Flexible Back-Of-Cab Options
With the Cummins X15N, like with all natural gas-powered Kenworth trucks, customers can select factory frame drilling options for back of cab Cummins Clean Fuel Technologies or Hexagon Agility CNG/RNG fuel systems.
Additional non-factory fuel systems are available to ensure flexibility for any application or configuration of the natural gas fuel system, including rail mounted and body mounted fuel storage.
Back-of-cab natural gas fuel delivery systems can deliver up to a 175-diesel gallon equivalent (DGE), making the X15N an efficient diesel alternative for customers that require longer range and power from their engine.
"Over the last two decades, Kenworth has been instrumental in offering clean fuel solutions for heavy-duty truck fleets,” said Eric Bippus, Hexagon Agility EVP of sales and systems. “Together, we're driving adoption of affordable sustainability solutions forward. Our CNG/RNG ProCab (back of cab) and ProRail (side-mount) fuel systems are backed by decades of innovation with millions of miles driven by leading fleets that have chosen to partner with us.”
“The integration of the Cummins Clean Fuel Technologies fuel delivery system and X15N engine give Kenworth customers an added level of serviceability of both the engine and fuel delivery system because guidance for all service procedures is available on Cummins platforms like QuickServe Online,” said Mike Zimmerman, Cummins Clean Fuel Technologies general manager. “We think this powertrain combination enhances the overall value proposition of the vehicle and we’re excited to work with Kenworth and Cummins to continue to bring value to the customers.”
Earlier this year, Kenworth delivered a pre-production Kenworth T680 Daycab equipped with the X15N engine to UPS, marking the industry’s first truck with the new natural gas engine to be delivered.
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