The 1994-1998 12-valve 5.9L Cummins engine is highly sought after in the diesel world thanks to its reputation for making cheap, easy horsepower, its industrial construction, long-term durability, and simplistic nature. It is very similar to the original 1989-1993 5.9L, sharing the same block, head, rods, and displacement. However, its biggest difference is the Bosch P7100 injection pump, also known as the P-pump, which helped it meet 1994 emission standards by cutting down on particulate matter produced in-cylinder.
The Cummins-powered 1989-1993 Dodge pickups helped put Chrysler back on the map in the pickup segment, but the 1994 Ram took a massive bite out of the market share. The Cummins engine was the end-all, be-all for anyone looking to tow heavy and get impressive fuel economy while doing it. In 1995, Cummins produced engine number 100,000 for Dodge, followed by the quarter-million milestone being met just two years later. With that kind of exponential growth, it was clear for anyone to see that Cummins-powered Dodge Rams were in high demand.
If you wanted the higher horsepower, bigger torque version of the 5.9L Cummins, you had to opt for a manual gearbox beginning in 1994. For the 1994 and 1995 model year Ram 2500 and 3500s, the five-speed NV4500 came bolted to the 175hp, 420 lb-ft variant, while the 47RH automatic was matched to the 160hp, 400 lb-ft engine. From 1996 to 1998, a more powerful 215hp, 440 lb-ft Cummins was available with the NV4500, while the new 47RE four-speed auto was joined with a 180hp, 420 lb-ft 5.9L.
The simplicity, reliability, and power of the 12-valve 5.9L Cummins engine has made it a favorite among diesel enthusiasts, and it remains a popular choice for those looking to build a performance diesel truck.