Cummins Diesel Engine

Cummins Diesel Engines Reliability

The Cummins Diesel Engines is the latest engine of the B 6.7 series that released 24 valve turbodiesel and straight-six for the Dodge Ram trucks. It was introduced in 2007. The B 6.7 Cummins is still present in the Ram 2500 and 3500+ trucks to this date. It has been through a few updates over the years. 

In 2021, the B 6.7 Cummins offers horsepower and torque values of 400hp and 1000tq. It is associated with the Cummins name of some best light truck diesel engines. We know that no engine is perfect and the same applies to the 6.7 Cummins diesel which is not the exception.  In the article, the most common problems in the Dodge Ram B 6.7 Cummins engine are as well overall reliability is discussed with their pros and cons.

Five B 6.7 Cummins Problems:-

Following are the five common problems of B 6.7:-

  1. Clogged Diesel particular filter (DPF)
  2. Turbo failure
  3. Head gasket
  4. Fuel dilution
  5. EGR cooler

1. Clogged DPF:-

The Diesel particulate filter(DPF) clogging is one of the common problems that occur in the Dodge Ram 6.7 Cummins. The Chrysler asks me to avoid the diesel exhaust fluid (DEF). Without Diesel particular filter, the B 6.7 diesel must run a little bit on the richer side to reduce NOX emissions. This may lead to more particulates, which can quickly clog the Diesel particular filter (DPF). 

The clogging issues created a lot of problems that rolled out dodge multiple PCM re-flashes to reduce its occurrence. In the year 2013, Ram pickup trucks receive SCR emissions control systems which may also lead to the exhaust of diesel fluid. This also helps in the reduction of particulates, therefore DPF clogging increases in the later years 6.7 Cummins. It also affects many trucks – especially as the mileage builds up.

2. Turbo failure:-

Turbo problems or failures are one of the most common problems on model B6.7 Cummins engines. It happens anywhere because turbochargers take a lot of abuse that can damage it. Therefore the experts give it the name of a turbo failure, but there are certain issues that don’t result in the complete failure of Turbochargers. 

Issues occur in B6.7 common Turbo:-

Following are the issues that occur with the 6.7 Cummins turbo include:-

  • Leaking oil seals
  • Worn bearings (too much shaft play)
  • Sticking VGT parts
  • Compressor or turbine wheel damage

3. Head gasket:-

The Head gasket problems of the B 6.7 Cummins are not able to work in actuality. But if we compared it with the previous 5.9 Cummins engines, then B6.7 runs into the issue a lot of frequencies. It may also have to do with the sheer power and torque the Dodge Ram 6.7 makes. It is also said that the High cylinder pressure is responsible for the head gasket failures.

ISB 6.7 Head Gasket Failure Symptoms:-

Following are the symptoms of head gasket failure ISB 6.7:-

  • White’s smoke with the sweet smell
  • Oil mixed with coolant
  • Coolant mixed with oil
  • Overheating

4. Fuel dilution:-

The fuel dilution of oil is natural on the B 6.7 diesel engine. The dilution can be inherent in the way the engine manages to regenerate. This occurs in the particulates that are trapped in and burned for cleaner emissions. It does not use the 7th injector to generate fuel into the exhaust. But in this, the fuel injectors spray a little bit of fuel into the exhaust stream which leads to the cylinder’s exhaust strokes.

The fuel dilution also allows small amounts of fuel to stick into the cylinder wall in which the fuel mixes with the oil. This problem occurs most frequently in almost all diesel engines. The few B 6.7 Cummins diesel may have too much fuel dilution. It has an acceptable limit of 5% in the dilution.

Avoid Cummins 6.7L Fuel Dilution:-

Following are the basic points to avoid cumins in the fuel dilution:-

  • Allow engine to warm up
  • Avoid extended idling

 5. EGR cooler:-

The EGR problems are most common in modern diesel trucks. The B6.7 Cummins also suffer from the same problem. The EGR valve and cooler that is placed in the B 6.7 Cummins suffers from these problems most probably at higher mileage. The EGR also suffers from some legal concerns due to these emissions laws. Therefore to solve this problem, it is a good idea to replace these parts or remove these parts that lead the trouble, if your dodge ram B 6.7 has higher mileage.


The above article tells you about the problems that may occur in the Dodge Ram B 6.7 and how to solve those problems in the best possible way.

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