The National Highway Traffic Safety Administration (NHTSA), the U.S. equivalent of Transport Canada, has opened an investigation into a potential engine-stall problem that could affect 600,000 Ram HD pickup trucks equipped with the Cummins 6.7L (turbo) diesel engine.
In total, the agency has received 22 complaints and two reports of motorists experiencing stalling or loss of power.
The investigation, which officially started on October 14, includes the 2019 and 2020 2500 and 3500 models, as well as the even more rugged 4500 and 5500 commercial versions. At the heart of NHTSA's inquiry are the high-pressure fuel pumps, as failures have been identified there that are believed to be the direct cause of the complaints. In most cases, the problem occurred at speeds above 40 mph and most importantly, the vehicles were unable to restart afterwards.
This isn't the first time Ram diesel truck fuel pumps have come under scrutiny. Ram issued a technical service bulletin in June 2020 to its dealers seeking information on issues with Ram diesel trucks from the 2018 to 2020 model years. The bulletin in question has since undergone several revisions. According to NHTSA, the responses have led Ram to focus on fuel pumps. Automotive website Motor1 reached out to Stellantis' truck division for additional information on the situation, and received this official statement: