The relationship between Chrysler and Cummins goes back to the mid-1980s. Back in those days, Chrysler was the only one of the big three automakers that did not have a diesel engine in their model lineup. In 1978, General Motors was the first to offer a diesel engine and their Oldsmobile 350 Diesel was an existing V8 design that they retooled for diesel use. Ford followed in the early eighties with a 6.9L V-8 diesel that they bought from International Harvester. Both of these engines were normally-aspirated and offered power similar to the gasoline powered versions. Then Chrysler got involved.
In 1981, Chrysler sourced their first diesel from Mitsubishi. It was a 4.0 liter, in-line six diesel which was thrifty and reliable. At 105 hp and a dismal 169 lb-ft of torque, it was considered relatively underpowered, though. However, the diesel engine proved popular enough that the company realized that needed a diesel permanently in their lineup, just a much more powerful one.
The solution to the problem came in the form of the Cummins B-series 6 cylinder engine. Cummins was a natural. They had a stellar name in the commercial equipment business and the engines were rock-solid. The timing was perfect too. In the mid 1980s, Chrysler was in the midst of retooling the truck line and Cummins was marketing their new medium-duty diesel engine line. It was a match made in heaven. In 1989, the Cummins B-series engine first appeared in the Chrysler’s new RAM pickup line.
Interestingly, the standard Cummins B-series was far too much engine for the RAM trucks when the project first began. It had a potential torque output over 500 lb-ft in commercial applications and had to be detuned for the RAM trucks. Although the horsepower of the resultant version, was 160 hp, similar to that of the Ford and Chevy diesels, the torque of the Cummins engine at 400lb-ft was far superior. The sales result? The Fords and Chevys never had a chance. The RAM trucks with Cummins engines were a huge hit and sales were simply off the charts.
The history of the Chrysler-Cummings relationship continues today. With a specification that would seem inconceivable just a few years ago, the 2015 RAM HD trucks will offer the latest generation 6.7-liter Cummins Turbo Diesel with an Aisin six-speed automatic. The specs? 385 hp and a mind-blowing 850 lb-ft of torque. The idea that we would be approaching the 1000-lb-ft mark in a standard factory-supplied diesel pickup is hard to believe, but we're just probably only a few years away from it now.
Courtesy of: Thompson Chrysler Jeep Dodge Ram