Cummings Diesels

Posted on 30 November, 2015

Cummings DieselsBack in the 1980s, Chrysler was the only one of the big three American automakers that did not have a diesel engine in their model lineup. In 1978, General Motors offered a 350 Diesel in their Oldsmobile model line. It was an existing V8 gasoline-powered 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 (i.e. no turbochargers) and offered power similar to the gasoline powered versions.

Knowing that the competition was taking sales from them, Chrysler jumped into the diesel marketplace in 1981.  Their first engine came from Mitsubishi. It was a 4.0 liter, in-line six which was thrifty and reliable.  At 105 hp and a weak 169 lb-ft of torque, it was considered relatively underpowered, especially in the Ram trucks. However, the diesel option proved popular enough that the company realized that needed a diesel permanently in their lineup, just a much more powerful one.  That’s when the engineers at Chrysler started to search for a world class diesel that they could source.

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 their 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 400 lb-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.

As a testament to the value that Cumming brought to Chrysler, one doesn’t need to look much further than the resale of Cumming-powered RAM trucks.  These vehicles resell for far higher values that any other truck in their year range.  It would not be an understatement to say that this is one vehicle that virtually has  cult following.

The history of the Chrysler-Cummings relationship continues today.  With a specification that would seem inconceivable just a few years ago, jeepcheap.com tells us that the 2016 RAM HD trucks offer the latest generation 6.7-liter Cummins Turbo Diesel with an Aisin six-speed automatic. Wonder what the specs are? Try some 385 hp and a mind-blowing 850 lb-ft of torque. The idea that any company 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:  Thomson Ram Trucks