Ram heavy-duty diesel trucks are being investigated by the NHTSA after it received numerous complaints about potential safety issues. Two field reports point the finger at stalls and power loss. The potential fuel pump failures could involve over 600,000 Ram heavy-duty trucks.

The Ram diesel trucks involved are the 3500, 4500 and 5500

Ram’s heavy-duty trucks include 2500, 3500, 4500, and 5500 from the most recent years they have been made. The diesel engine is a 6.7-liter Cummins turbodiesel. Most but not all of the Ram trucks in these series have the diesel option. The other available engine is the 6.4-liter Hemi V8. 

In a typical NHTSA investigation, most begin with an evaluation first. NHTSA engineers collect data from the manufacturer as well as their take on the potential issue. At that point, it can issue a voluntary recall. 

If it is satisfied it is not a widespread issue the agency will close the case. Or in the case of safety-related problems, it may ask the manufacturer to issue a recall. This investigation began last week. 

Fuel pump failures have been reported in many diesel engines

From field reports, the NHTSA has found that these fuel pump failures occur at speeds over 25 mph according to Automotive News. In all cases, the trucks stalled out after losing power. “We will, as always, cooperate fully with NHTSA’s investigation while continuing our own fact-finding in support of our customers,” Stellantis spokesman Eric Mayne said in a statement to Automotive News. 

For its part, Stellantis has issued a warranty notice. This was back in 2019, so it has been aware of the issue for some time. It included 2018-2019 models with the diesel engine. An inspection campaign by Stellantis collected high-pressure fuel pumps. Both Stellantis and the manufacturer reviewed the findings. 

Numerous recall campaigns have involved Ram diesel trucks

There have been a number of recalls for the Ram 3500 with the diesel engine. In June the recall was over improper engine calibrations. Electrical gremlins cause another recall in March. Problems with the Cummins diesel oil and lubrication forced a recall in August 2020. A cooling fan was an issue that resulted in a recall at the beginning of 2020. 

In all, there have been 71 recalls for Ram diesel engine problems going back several years. Many were related to the Takata airbag debacle. But recent powertrain and electrical problems have also mounted. 

For more information, you can see if your Ram truck is part of the recall at the official Ram recall center. You can also contact the NHTSA, or call your local Ram dealership.