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Daimler Turns to Cummins for Medium-Duty Engines
Cummins will take over the development, production and delivery of medium-duty engines for Daimler Trucks and Buses around the world by the second half of the decade.

Daimler Truck AG announced it will halt production of medium-duty engine systems by 2029, including phasing out the Detroit DD5 engine (pictured).
Photo: Deborah Lockridge
Cummins will take over the development, production and delivery of medium-duty engines for Daimler Trucks and Buses around the world by the second half of the decade. Daimler Truck AG announced it will halt production of medium-duty engine systems by 2029, and has signed a memorandum of understanding with Cummins.
The new partnership will mean Daimler’s Detriot DD5 and DD8 medium-duty engines, introduced in 2016 and 2018, respectively, will also be phased out.
“We’ll continue to offer the DD5 and DD8 until the second half of the decade with aftersales and warranty support continuing for years to follow,” Daimler Trucks North America officials told Heavy Duty Trucking.
The changover to European vehicle emissions standards, Euro VII, would mean Daimler would have to invest “considerable resources” to further the development of their medium-duty engine portfolio, Daimler Truck’s Board of Management Chairman Martin Daum said in a press release. Instead, the company is focusing on other segments.
“We are now freeing up these funds to focus them on the technologies that are crucial to our long-term corporate success in the transformation of our industry,” Daum said. And that means heavy-duty engines and alternative drive technologies.
Daimler to Focus on Heavy-Duty, Zero-Emissions
Daimler anticipates the partnership with Cummins will enable it to accelerate its development efforts on alternative and emerging technologies, including non-diesel engines. In the future, Daimler Truck AG will focus on the further progression of zero-emission drive technologies, as well as further development of commercial heavy-duty drivetrains, it said.
The production of the current medium-duty engine generation by Daimler Truck AG will end with the start of production of the Cummins engines at the Mercedes-Benz campus in Mannheim, Germany.
The partners announced they will evaluate a broader global strategic partnership through identifying potential synergies in areas such as powertrain components and engine system components.
The Daimler heavy-duty engine platform (HDEP) for the heavy-duty vehicle segment of Daimler Trucks and Buses will remain in the Daimler Truck AG portfolio. The HDEP engine family will continue to be manufactured by the global production network in Mannheim and in Detroit, Michigan, and fitted in heavy-duty trucks, in touring coaches, as well as in third-party products worldwide.
Production of Medium-Duty Cummins Engines
Cummins will establish an engine plant within the Mercedes-Benz campus in Mannheim, efficiently using existing resources to produce medium-duty engines compliant with the Euro VII emissions standard.
Under the partnership, Daimler Truck AG and Cummins will help maintain employment at the Mannheim plant, Daimler officials said.
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