The Fascinating History of the Cummins Engine

Cummins is a name most auto enthusiasts associate with diesel engines in commercial vehicles, fleets, and big trucks. The Cummins name is probably best known within most truck circles for powering the Ram series of light and heavy-duty pickups. You’ll find plenty of them in a variety of different trims where the turbo-diesel option is made available. Heck, it’s not even uncommon to find a used Ram 1500, 2500, or 3500 with the Cummins engine attached and all the low-end torque that comes with the engine. For those of you curious how Cummins got its start, it’s a much more interesting story than you may have originally thought.

Humble Beginnings and Big Dreams

The Cummins corporation is a multinational business that extends to more than 190 countries. It has roots laid down all over the world, producing diesel engines for a number of different travel purposes, from cars, trucks, trains, buses, tractors, and tanks. If you can find a vehicle guzzling diesel, a Cummins won’t be too far away.

It wasn’t all peaches and cream for this multi-billion dollar corporation. The Cummins engine actually had its start with more humble beginnings, like a lot of starter ventures in the automotive industry. In fact, the company, named after its founder, Clessie Cummins, was anything but a big business. It was a struggling company that, at one point, almost lost all its funding due to a number of circumstances that nearly railroaded the diesel engine behemoth before it even got its feet firmly planted in the ground.

It all started on a farm in Indiana back in 1888, when Clessie Lyle Cummins was born. Through an early life of hard work, thanks to unbridled ambition pumping through his veins, the unassuming farm boy would pay his dues doing menial work until he eventually set his sights on bigger things. Without a formal education, Clessie worked his way into becoming a chauffeur for a banker named William Irwin in 1910. Clessie would later work as a mechanic, eventually joining a pit crew just a year later in 1911. That’s where he learned about mechanical engineering by tinkering with engines, which ultimately led to him designing his own engine.

The purpose of the diesel engine was to get more performance and mileage out of the engine compared to traditional gasoline engines. More power with less fuel expenditure would make a great pitch for farmers and truckers across the nation, especially since that’s where Clessie had his roots planted. Irwin would later come back into the life of Clessie, playing a significant role in the mechanic’s destiny to achieve big things. The banker would invest in the Cummins Motor Company in 1919 as Clessie would pursue perfecting and improving the diesel engine.

Improvement Through Reduction

At the time, most engineers were trying to improve the power and performance output of combustion-based motors. Clessie’s pursuits differed with his diesel configuration because it concentrated on reducing weight and increasing efficiency. This is what made the Cummins diesel engine different from other diesel engines of the time, as the focus from Clessie was on improving the fuel-oil combustion process while reducing waste and particulate matter.

Clessie improved the fuel injection process and reduced the expenditure of fuel and oil to improve combustion efficiency. In turn, this allowed the diesel engine to achieve more power and longevity while reducing fuel use. In short, the process focused on reducing weight by removing unnecessary parts, improving efficiency, and getting the most out of the engine. You can see this in more recent Cummins-powered trucks, whether it’s in new or used Ram 1500, 2500, 3500, medium duty, heavy duty, or fleet trucks.

Fast Times With Heavy Loads

In 1931 Clessie Cummins would take a shot at changing motorsports forever when a modified 4-cylinder Cummins Model U engine would be used in the Indianapolis 500. After being granted a provisional spot in the race and allowed use of a larger engine thanks to relaxed rules, Clessie would work with Augie Dusenberg to fit the custom 4-cylinder into a modified Duesenberg chassis2. Clessie was later denied any race earnings due to being given a spot in the race rather than qualifying for it.

The combination proved successful, with the 4-cylinder Cummins Model U engine producing up to 85 horsepower at 1,500 revolutions per minute. The vehicle was named the Cummins Diesel Special, and it weighed in at over 1,600 pounds. This heavy but reliable race car combining Duesenberg aerodynamics with Cummins engineering was driven by Dave Evans, managing to average around 96 miles per hour during qualifying.

Despite being the slowest vehicle in the race, Clessie smartly relied on the diesel’s lack of needing to be refueled to take advantage of track positions. While other racers were pitting, the Cummins kept on trucking. In fact, it managed to finish the entire race on a single tank of diesel without ever stopping, moving up from 43rd place to 13th by the final lap.

Hard Times Make For Good Trucks

Proving to be successful on the race track wasn’t quite the same as being successful in the fleet world, though. During that time, the great depression ravaged sales and caused a slow uptick in adopting Cummins’ diesel engine. The great depression put a hamper on the potential success of the Cummins Motor Company due to farmers ordering diesel engines to carry out their harvesting duties and then returning the engine when they were done using their tractors for the year. This deeply cut into the potential profits, and Irwin was ready to pull the plug on his investments in Clessie’s motor company, which, at that point, had relied on staying afloat by supplying engines for yachts.

However, things turned around when Clessie convinced Irwin to use his diesel engines in the trucks that were part of a fleet to transport goods to the grocery chains that Irwin operated. This proved to be a turning point in Irwin understanding how useful and cost-effective diesel engines would become. The Cummins engine was capable of outputting the power necessary to haul large loads while operating with reduced fuel costs compared to traditional gasoline engines.

Success, Growth, and Expansion

The adaptation of Cummins diesel engines in the fleet line of Irwin’s grocer trucks proved successful beyond imagination. The efficiency and reliability of the engines developed a reputation that spread like wildfire throughout the industry among unionized truck drivers. From then onward, the growth and success of the Cummins became a consistent factor, resulting in the company turning profits for the first time in 1937 since its inception.

With an upward trajectory of success, thanks in large part to competitors also buying Cummins diesel engines, evolution was the company’s next big priority. This included re-engineering the diesel engine for more efficiency, power, and torque. This resulted in the first turbo-diesel from Cummins coming into its own in 1952. The turbo-diesel was a game-changer because it provided 50% more horsepower at the same fuel cost. This was due to the turbine being spooled up by the exhaust gasses, which was used to force more air back into the system and generate even more power.

Diesel-Powered Light-Duty Trucks

Even while market share and profits in the truck market for Cummins began to decline in the 1960s, the company maintained a diverse portfolio of other interests while making breakthroughs in diesel technologies. The focus throughout the 1960s, though unsuccessful from a market penetration standpoint, was improving diesel-powered light-duty pickups. This would pay off in the long run despite the company having a tough go of sales throughout the 1960s with non-fleet market segments.

Improvements to the diesel engine continued well into the 1970s, where Cummins stepped out well ahead of the competition, offering more horsepower and stability with lower fuel costs. Despite the initial upfront costs of diesel engines compared to gasoline engines, they did offer long-term savings for those who drove regularly. This would pave the way for the Cummins B Series, one of the most popular diesel engines by the company, which would power the Ram trucks throughout the late 1980s and 1990s.

After other companies began to eat into Cummins’ market share with electronic engine management, Cummins caught on quickly and began utilizing electronic engine management as well, along with improved performance by Holset Engineering’s highly efficient turbocharger. This would open the door for the 4-cylinder and 6-cylinder engines appearing in the Ram series of consumer pickups starting in 1989, where Cummins struck a deal to provide their large turbocharged engines in the equally large Ram, which proved to be quite successful4.

A Future of Diesel-Powered Rams

While emission restrictions became more prominent, and a few controversies set the Cummins Corporation behind in profits, the commitment to improving diesel-powered vehicles stayed consistent. From introducing high pressure common rail systems into the mechanical ecosystem for Ram trucks back in the early 2000s, to embracing variable geometry turbochargers to reduce turbo lag, there was no shortage of innovation and improvements. Eventually, the times changed and emissions regulations altered the powertrain landscape, which is why newer light-duty Ram trucks are now powered by VM Motori’s EcoDiesel. This means you can only find a Cummins in a used Ram 1500 series, as far as light-duty trucks are concerned.

However, the company is still the go-to solution for the Ram’s newer 3500 series. It proves that Cummins still has a place in today’s marketplace for those looking for a reliable heavy-duty truck (or a reliable used light-duty diesel truck). Regardless of the ups and downs the company has endured, it’s a nice reminder that even some of today’s largest multinational corporations had humble beginnings. For Cummins, the company was born out of the hard work and ingenuity of an American farm boy with big ideas and unshakable determination.