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Dodge Diesel History

The Cummins/Dodge Partnership



Face it, Dodge/Ram diesel owners are Cummins customers first, and Chrysler customers second. The Cummins turbodiesel has always been the saving grace of Ram's 3/4 and 1 ton trucks, as well as their commercial truck business. With the reputation that Cummins has earned in their ventures in the medium and heavy duty market, it's no surprise that the big "C" mounted on the fender is the main attraction.


Dodge entered the diesel marketplace considerably behind Ford and General Motors - but they came loaded for bear. In 1989, Dodge teamed up with Cummins to offer the 160 horsepower, 400 lb-ft producing 5.9L turbodiesel. The 5.9L 12v Cummins produced more horsepower and torque than both Ford and GM, while maintaining healthy fuel economy. The 5.9L was also the first and remains the only I-6 offered amongst the Big 3. The engine gained a significant amount of attention for its capability, as well its uniqueness. The Cummins was clear competition for Ford, who was also offering a true medium duty engine in their pickups. The infamous 12 valve Cummins lasted until the 1998 model year, where it would be replaced by an equally popular, more powerful 24 valve version.


Mid-model year for 1998, the electronically controlled 5.9L ISB replaced the 12 valve for good. Originally outfitted with a mechanical injection pump, the ISB would receive a Bosch high pressure common rail injection system for the 2003 MY, which proved to be a huge game changer. The ISB is well known for performance potential in the aftermarket. Not only is it easily to push more horsepower and torque out of this engine, but the engine's robust design can take a considerable amount of abuse on the factory long block.


Plagued by stringent emissions regulations, the 5.9L 24v was retired midway through the 2007 model year in favor of a larger, 6.7L Cummins I-6 turbodiesel. The engine featured the same DPF (diesel particulate filter) system that would hurt Ford, GMC, and Chevrolet trucks. However, the 6.7L Cummins seemed to have more difficulty with reoccuring clogged particulate filters than their competitors, but this would slowly be worked out over the course of several years.


For 2013, in an effort to keep up with Ford's Power Stroke and GM's Duramax, Ram Trucks (formerly Dodge) and Cummins launched a high output version of the 6.7L, which produces 850 lb-ft of torque and 385 horsepower, and comes mated to a medium duty Aisin transmission. Seeing as Chrysler's downfall in the marketplace had been subpar transmissions for so many years, the change has been more than welcomed by future customers and current owners. The 6.7L Cummins is still currently being offered by Cummins/Ram Trucks.