1994-1998 Dodge 5.9L Cummins 12V Performance Parts and Accessories

The 5.9L 12-valve Cummins Turbo Diesel engine in these models produces 175-215 horsepower and 420-440 lb-ft of torque, depending on the year and configuration.

At stock height, the largest tire size that typically fits is 33 inches on 16-inch wheels. 35-inch tires usually require a leveling kit or trimming, particularly on 4WD models.

The 5.9L 12-valve Cummins is legendary for its durability and reliability, often praised as one of the toughest diesel engines. However, the 47RH and 47RE automatic transmissions have a reputation for being weaker, especially under heavy loads. The NV4500 5-speed manual is the more reliable option for towing.

Fuel economy for these trucks ranges from 14-20 MPG, with highway driving producing the best results. Towing or off-road driving tends to drop fuel efficiency to the lower end of the spectrum.

The Ram 3500 can tow up to 12,500 pounds, depending on configuration, while the Ram 2500 has a maximum towing capacity of around 10,500 pounds when properly equipped.

The 5.9L 12-valve Cummins is highly responsive to tuning and upgrades. Upgrading turbos, cold air intakes, and exhaust systems can provide 100+ horsepower. The P7100 injection pump in the 12-valve is well-known for being extremely tunable with mechanical adjustments.

There are several lift kit options, ranging from 2.5-inch leveling kits to 6-inch suspension lifts. Brands like Rough Country, BDS, and Skyjacker offer kits that improve off-road performance and provide extra clearance for larger tires. With the age of these trucks, it’s a great idea to go through and check all steering and suspension components before simply adding a lift and larger tires.

The 5.9L 12-valve Cummins is incredibly robust, but the automatic transmissions (47RH and 47RE) are weak points, especially under heavy towing. Manual transmissions (NV4500) are more reliable but prone to 5th gear issues under heavy load. The Killer Dowel Pin (KDP) is another issue specific to the first few generations of the 12-valve Cummins, where the dowel pin under the timing cover can dislodge and cause catastrophic engine damage if not addressed.

With the right modifications, like lift kits, off-road tires, and skid plates, these trucks perform well off-road. The solid axle design and durable frame make them ideal candidates for off-road builds, though factory suspension was designed more for towing than rugged terrain.

The Ram 3500 has a maximum payload capacity of 4,050 pounds, while the Ram 2500 can carry up to 2,750 pounds, depending on configuration.