Paccar Inc. and Cummins Inc. announce an agreement to jointly develop proprietary versions of Cummins’ 6L and 8L diesel engines.

The truck powerplants, which will be badged as Paccar units, will be installed exclusively in Paccar’s Kenworth- and Peterbilt-brand North American medium-duty commercial vehicles, Paccar says.

Peterbilt and Kenworth Class 8 heavy-duty trucks will continue to offer various engine choices from several manufacturers.

“This agreement is a natural extension of the engine collaboration, which DAF (Trucks N.V.) and Cummins have had in Europe for seven years,” Paccar President Tom Plimpton says. DAF also is owned by Paccar.

The North American agreement will better position Paccar against competitors that have their own medium-duty engines, while also significantly reducing development costs for meeting the U.S. Environmental Protection Agency’s ’07 heavy-truck emissions requirements, he adds.