1994–1998 DODGE RAM 2500 AND 3500 5.9L CUMMINS

This is really the truck that started the diesel wars. If you hate wires and other electronics, the 12-valve 5.9L Cummins is the only truck engine you’ll even consider.

The mechanical P-7100 fuel pump is virtually bombproof. This engine has the kind of dirt-simple technology and durability you find in an old bulldozer. With a little help from the many different aftermarket parts available for it, the engine can be easily modified to make more power and torque than stock. The earlier, square-body Cummins trucks have a similar engine, but they don’t enjoy the same aftermarket support. Watch the exhaust gas temperature on modified engines, because excessive heat will damage the exhaust manifold and cause leaks. Heavy-duty aftermarket manifolds are available to remedy this problem.

The automatic transmissions used in these trucks are marginal, even in stock applications that see heavy loads. The only real solution is to dig deep into your pockets and order a properly built heavy-duty transmission and torque converter from one of the many companies that specialize in diesel transmissions. Don’t waste your time trying to save a buck with the one-a-day tranny guy down the street; you’ll only be throwing your money and time into the trash.

The NV4500 five-speed manual transmission that came in these trucks is extremely durable. However, turned-up trucks hauling heavy loads will need to have a locking retainer installed onto the fifth gear. Some people simply tackweld the factory nut in place. A heavy-duty clutch is also a good plan.

There is an unbelievable number of aftermarket lift kits, suspension mods and axle upgrades available for this solid-axle Dodge Ram 4x4. So, if your plan is to take it in the dirt, the sky’s the limit. The front axle vacuum disconnect can be problematic if the vacuum lines are damaged; however, there are aftermarket kits available to convert it to a mechanical linkage or eliminate the disconnecting axle completely.

ENGINE: CUMMINS 5.9L 6BT 12-VALVE INLINE-SIX

ASPIRATION: DIRECT-INJECTED, INTERCOOLED SINGLE TURBO OUTPUT: 1994–1995: 175 HP (MANUAL); 160 HP (AUTO); 420 LB-FT (MANUAL); 400 LB-FT (AUTO)

1996–1998: 215 HP (MANUAL); 180 HP (AUTO); 440 LB-FT (MANUAL); 420 LB-FT (AUTO)