Clessie Cummins worked as a chauffeur and mechanic for William Irwin, a banker in Columbus, Indiana. Although he had no formal education beyond the eighth grade, Cummins had a keen knack for the mechanical, which was noticed by Irwin. Legend has it that when Cummins was only 11 years old, he built his own steam engine from molten cast iron he poured into wooden blocks that served as molds. His homebuilt steam engine was used to pump water for his father's farm.

Cummins was convinced diesels had great potential as powerplants for cars and trucks. To demonstrate their feasibility and efficiency, he installed one of his engines into a 1926 Packard Touring sedan, which he drove from Indiana to New York City with the intent of presenting it at the 1930 New York auto show. The car covered nearly 800 miles having used only 30 gallons of fuel -- an average of 26 mpg, an astoundingly efficient figure for the day. Because he was not officially registered as an exhibitor at the show, Cummins was turned away. The scenario repeated in nearby Atlantic City, where Cummins also showed the car. This time, he rented space across the convention hall to display the car and ended up being an even bigger attraction than most of the official exhibits at the show.

Wanting to follow up his success with the Packard, in 1935 Cummins swapped a new lightweight six-cylinder diesel into an Auburn 851 sedan, which achieved an incredible for the time (and good even for today) 40 mpg. The car also reached an equally impressive top speed of 90 mph. Cummins hoped for a long-term relationship with the automaker, but Auburn went out of business only a year later.

1955 Clessie Cummins went on to found his own company, Cummins Enterprises.

He had been working on an experimental exhaust brake and later partnered with the Jacobs Chuck Company to create another icon of the diesel world, the famed Jake Brake exhaust brake.

Cummins has retained dominance of the commercial diesel market, holding more than a 40-percent market share among Class 8 trucks for 2012 year to date.

Probably the biggest single factor that moved recognition of the Cummins name beyond the commercial truck sector was the company's partnership with Chrysler. By the mid-1980s, Chrysler was the only one of the Detroit Three automakers that did not offer a diesel option in its full-size trucks. General Motors was first, offering a diesel in its full-size trucks starting in 1978. Ford followed by offering a diesel sourced from International Harvester in 1983. Both of these engines were naturally aspirated V-8s and offered power comparable to their smaller-displacement gasoline counterparts with better fuel efficiency, but neither was particularly known for its torque output, characteristic of today’s modern turbodiesels.

Dodge had previously offered a diesel in the Ram's D-series predecessor in 1978 in the form of a 4.0-liter naturally aspirated Mitsubishi inline-six. The engine was economical, but produced only 105 hp and 169 lb-ft of torque and was considered woefully underpowered. It was offered for just one model year.

In 1983, Cummins requested the engine compartment drawings to check fitment of the 5.9L B-series under the hood. From there, a running mock-up engine was shipped to Chrysler for use in a demonstration vehicle. After the technical review of the truck and the realization that there were no major issues, the project was kicked off formally."

With potential output well above 200 hp and 500 lb-ft in commercial applications, the engine had to be detuned for use in the Ram. Taking into consideration emissions regulations, driveline strength and reliability, the final calibration for the 1989 Ram was 160 hp and 400 lb-ft of torque.

You’ll find Cummins engines powering many of your favorite trucks, and a number of industries use Heavy-Duty and High-Power Cummins engines — including construction, mining, marine, oil and gas, and railroad.

For many years, Ford offered Cummins diesel engines in their medium-duty pickups. However, they remain an independent company supplying engine to both RAM trucks and a commercial truck makers like:

• International- ProStar, 9900i, LoneStar, PayStar and HX models
• Freightliner-Cascadia, Coronado, and 122SD models
• Kenworth- T660, T680, T800, T880, W900, and C500 models
• Peterbilt- 389, 579, and 587

And this is just the beginning of the use of Cummins engines in high-powered machines!