4 Common Problems Ram 2500 Diesel Owners Should Know About

The Ram 2500 equipped with the legendary 6.7-liter Cummins diesel has built a reputation for durability and serious towing capability. These trucks are capable of hauling massive loads and often rack up hundreds of thousands of miles when properly maintained.

But modern diesel pickups are far more complex than they used to be. Beyond the engine itself, owners have to deal with sophisticated fuel systems, emissions equipment, turbochargers, and transmissions. And when one of those components fails, repair bills can quickly climb into the thousands.

Here are four of the most common issues Ram 2500 diesel owners and buyers should be aware of.

CP4 Fuel Pump Failures on 2019-2020 Models

One of the most notorious problems affects 2019 and 2020 Ram 2500 trucks. During those model years, Ram switched from the proven Bosch CP3 fuel pump to the Bosch CP4.2 high-pressure pump.

Unfortunately, when the CP4 fails, it often fails catastrophically.

Owners have reported sudden power loss, engine shutdowns, rough running, and no-start conditions. In some cases, trucks stalled while towing or driving at highway speeds.

The bigger problem occurs when the pump sends metal debris throughout the entire fuel system. Once contamination spreads, repairs may require replacement of injectors, fuel rails, lines, filters, and even the fuel tank.

Repair bills have reached $10,000 or more in severe cases.

Stellantis eventually addressed the issue through Recall Y78, which includes replacing the high-pressure pump, updating the engine software, and inspecting other fuel system components.

68RFE Transmission Problems

For nearly two decades, most Ram 2500 diesel models relied on the 68RFE six-speed automatic transmission.

While many owners have logged high mileage without trouble, the transmission's overdrive section has developed a reputation for weakness, especially in trucks used for heavy towing.

Symptoms often include:

• Harsh shifting;
• Delayed gear engagement;
• Gear hunting;
• RPM flare between shifts;
• Limp mode;
• Loss of higher gears.

Some owners also report shuddering and slipping under load. In more severe cases, internal clutch failures and valve body issues require expensive rebuilds.

Ram never issued a broad recall for these complaints. Instead, fixes were generally handled through software updates and individual repairs.

Beginning with the 2025 model year, Ram replaced the 68RFE with the newer TorqueFlite HD eight-speed transmission.

DPF Clogging and Exhaust Filter Warnings

Like every modern diesel truck, the Ram 2500 uses a diesel particulate filter (DPF) to reduce emissions.

The system relies on regeneration cycles that burn accumulated soot. However, trucks that spend most of their lives on short trips or idling may not generate enough heat to complete the cleaning process.

As soot builds up, drivers may first see messages advising them to continue driving at highway speeds. If the condition worsens, warning lights, reduced power, and limp mode can follow.

Owners have reported trucks suddenly losing power and becoming nearly undriveable after receiving "Exhaust Filter Full" messages.

Repeated regeneration problems have also led to complaints involving exhaust odors, smoke, and leaks around emissions components.

Because driving habits play a major role, Ram never issued a widespread recall. However, Stellantis released several service bulletins and extended warranty coverage on certain 2021-2022 trucks through program X97.

Turbo Actuator and Exhaust Brake Failures

Another common complaint involves the variable-geometry turbocharger used on most 2013-2024 Ram 2500 diesels.

The electronic actuator that controls turbo vane position can fail due to overheating or communication errors.

When this happens, owners may experience:

• Sudden loss of power;
• Limp mode;
• Reduced turbo boost;
• Strange turbo noises;
• Exhaust brake malfunctions.

Some drivers have reported the exhaust brake remaining engaged when it shouldn't, making the truck feel sluggish even with the accelerator pressed.

Repair costs commonly range between $3,500 and $4,000.

Although no safety recall was issued, Stellantis extended warranty coverage for certain 2015 trucks under program X99. Eligible vehicles received coverage for up to 15 years or 150,000 miles.

Should Buyers Be Concerned?

Despite these known issues, the Ram 2500 remains one of the most capable heavy-duty pickups on the market. Many owners accumulate extremely high mileage with few major problems.

Still, prospective buyers—especially those shopping for used trucks—should understand that the Cummins badge alone doesn't guarantee trouble-free ownership.

Checking service records, verifying recall work, and understanding how a truck was used can make the difference between owning a dependable tow rig and facing repair bills that rival the price of a compact car.