Dig Deeper: Cummins X15N: The Right Engine at the Right Time?
Cummins X15N Natural-Gas Engine to be Offered in Kenworth, Peterbilt Trucks
Paccar plans to offer the new Cummins X15N natural gas engine in Kenworth and Peterbilt trucks, allowing fleets to achieve lower carbon emissions for long-haul transport using internal combustion engine technology.

Cummins X15N natural gas engine offers more power at a lighter weight than Cummins' 12L natural gas engine.
Photo: Cummins
Paccar plans to offer the new Cummins X15N natural gas engine in Kenworth and Peterbilt trucks. The X15N is the first natural gas engine to be specifically designed for heavy-duty truck applications with up to 500 hp output, according to an announcement. The engine will include the integration of the Cummins Clean Fuel Technologies fuel delivery system.
Paccar, Cummins, and several customers, including FedEx Freight and Knight-Swift, will demonstrate the ability to achieve lower carbon emissions for long-haul transport using internal combustion engine technology.
When operating on renewable natural gas, also known as RNG or biomethane, the X15N engine will be able to achieve major reductions in the lifecycle greenhouse gas emissions of Peterbilt and Kenworth trucks. This can range from a 90% reduction to carbon neutral, or even carbon negative, depending on the bio-source and waste feedstock used to produce the fuel.
The new X15N is capable of lower NOx levels than the 2024 EPA and CARB standards. The 1,850 ft-lbs. of peak torque output provided by the X15N will provide optimum performance when paired with Eaton Cummins Automated Transmission Technologies HD and XD Transmission.
The X15N is currently in production and fleet service in China, and plans are to start building the engine in Jamestown, New York, starting in 2024.
“The X15N is essential to our commitment to help customers reach net-zero greenhouse gas emissions and to improve NOx,” said Srikanth Padmanabhan, president of Cummins Engine Business. “Importantly for the customer, the X15N will reduce the cost of adopting low-emissions technologies for their fleet, and gives them the confidence to do so.”
Watch: Meet Cummins' New Natural Gas Truck Engine
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