What Cummins is in the 2nd gen?

1994-1998 12 Valve 5.9L Cummins Spec

Following in the footsteps of the first generation of Cummins is not easy. Dodge had great success with their first 5.9L Cummins engine and D250/350 trucks and they had to keep up the momentum. So they kept the 5.9L Cummins and made some tweaks to improve them. The term second-generation Cummins refers to Dodge diesel pickups manufactured between 1994 and 2002. There are two variants of the second generation Cummins. The 1994-1998 trucks had 12 valves and were very similar to previous truck engines. 1998.5-2002 trucks are equipped with a 5.9L Cummins engine with 24 valves. We'll discuss what makes these trucks unique and include a full list of 2nd Gen 5.9 Cummins specs below.

1994-1998 12V Cummins (12 Valve) Features

The first variant of the second generation Cummins had the ideal "p-pump" fuel injection pump. New injectors, a larger intercooler and new turbochargers were also introduced. These additions help reduce emissions compared to the 1st generation. They also give the 5.9L 12v engine better performance. The second-generation Cummins trucks produced more horsepower and torque than the previous model, but the horsepower and torque numbers depend on your transmission configuration. The 1994 Cummins-equipped Dodge Ram truck made 175 horsepower and 420 lb-ft of torque when equipped with the NV4500 5-speed manual transmission. A 1994 Cummins truck with an automatic 47RH transmission offer just 160 horsepower and 400 lb-ft of torque.

5.9L 12V Performance Specifications

FUEL INJECTION

Early second-generation Cummins featured a new fuel injection system with new injectors, injection pumps, and even the pistons were updated for better combustion events and lower emissions. The Bosch P7100 mechanical injection pump is without a doubt the most important component of this fuel system. The "P-Pump" injection pump provides better fuel delivery and can be upgraded for higher flow and performance. However, the P-Pump cannot do all the work alone. Fuel injectors were added to maintain higher fuel pressure. The piston fuel bowl design has been changed to provide better swirl and improve overall combustion quality.

Early second generation Cummins air intake

The second-generation Dodge Cummins added a larger intercooler and a new wastegate turbocharger. The original turbocharger offered on the 1994 Dodge Cummins was a wastegate variant of the turbocharger found on the first generation Cummins. This turbocharger is called the Holset H1C. Second generation Cummins trucks from late 1994 to 1998 had a different turbocharger. They have upgraded Holset HX35W or HX35 turbochargers. This turbo has been proven capable of not only maintaining stock boost levels, but has been known to withstand 40 psi.

The Engine of Choice for Diesel Racing and Sled Pulling

Today, late 12V Dodge Cummins trucks are the first choice for racing and high performance applications. Over 1,000 horsepower can easily be achieved, and these motors are capable of handling the extra power with some minor upgrades. Even as a daily driver, the 12V Cummins is ideal. Even with tuning and other performance upgrades, these diesels can last hundreds of thousands of miles before any major overhauls are done.

1998.5-2002 24V Cummins (24 valves) specification

In 1998, a revised version of the second generation Cummins was introduced. It retains the same body style but has major mechanical changes. The new 5.9-liter Cummins engine has 24 valves, or four valves per cylinder. The mechanical "P-Pump", officially known as the Bosch P7100 fuel injection pump, was replaced by a rotary electric VP44 injection pump. This fuel injection pump is one of the most common problems with second generation Cummins. Other second-generation Cummins specs have also changed, helping the Dodge truck stand slightly above its competition. The 1998 Dodge Ram truck with the 24-valve 5.9-liter Dodge Cummins engine produced 235 horsepower and 460 pound-feet of torque when paired to a 5-speed manual transmission. The 1998 truck with the automatic transmission made 215 horsepower and 420 lb-ft of torque.

24V 5.9L Cummins Performance Specifications

ENGINE CHANGES

Cummins dramatically changed the late second-generation Cummins engine. By doubling the valves, overall performance can be improved. Drivability is improved thanks to better throttle response. The 24V engine configuration also allows for better coolant flow compared to the previous 12V engine. Another significant change was the new "53" engine block. While Cummins engines are generally very reliable, the blocks marked "53" are prone to cracking. They have thinner walls, which overtime can cause coolant leaks. Therefore, trucks built before 1999 or after 2001 are more popular.

Fuel System

Switching to an electric rotary jet pump was a big step for Cummins. The VP44 fuel injection pump works with the ECU to control injection timing and fuel flow. An electric lift pump was introduced to help keep fuel pressure constant. This lift pump is actually one of the most common causes of VP44 pump failure. If it doesn't get a proper fuel supply, it's likely to break down. Highly recommend aftermarket lift pumps such as Air Dog or Fass systems! Mechanical injectors are still used on second-generation Dodge Cummins trucks, although they have switched to electric rotary fuel injection pumps. However, they were repositioned, which made servicing them easier, and improved the spray pattern for a better burn sequence.

Air Induction

The 24-valve 5.9L Cummins uses the same turbo as the 12V models from 1994-1998. All models up to 01' and 02' use the Holset HX35W. These years, trucks with automatic transmissions use HY35W turbochargers.

High Output 24V 5.9L Cummins

The second-generation late Cummins trucks are available in high-output configurations. High output 24V 5.9L Cummins with 6 speed manual transmission. This is slightly different from what we've seen Ram do so far. The manual transmission is nowhere near as capable as the Aisin automatic or even the standard 68RFE. Automatic transmissions in 2000-2002 were far worse than they are today. This NV5600 6-speed manual transmission is a better choice than earlier automatics, especially for adding aftermarket power.

The high-output truck makes 10 extra horsepower and 45 more lb-ft of torque from the factory. However, higher horsepower and torque figures are easily achievable, and manual transmissions make backing those big numbers very affordable. Check out our favorite second-generation Cummins performance upgrades post to find out which parts you need to add more horsepower and torque to your truck.

Second Generation Cummins Specifications

Because both the 12-valve and 24-valve versions of the Cummins engine appeared on the second generation Cummins, pay special attention to the year listed. Second-generation Cummins specifications will vary slightly between model years.