Ram Moves Away From The CP4.2 Injection Pump For 2021

Over the past few days, posts have been springing up on Facebook as people have been looking at 2021 Ram Heavy Duties, which are now landing on dealer lots. One thing that has been pointed out was a new injection pump on Cummins diesel equipped trucks. 

We reached out to Ram for clarification on the pump change and were told that Ram did indeed change the injection pump again for 2021. This change affects both the standard and high output versions of the Cummins inline-6 turbo diesel. While our rep wasn’t able to clarify exactly what the new pump is, it does bear a striking resemblance to the tried and true Bosch CP3 injection pump.

The 2019 Ram Heavy Duty models debuted with the new 6.7 liter Cummins Turbo Diesel inline-6, the first to break the 1,000lb. Ft of torque barrier, and featured the Bosch CP4.2 injection pump. There was an initial outcry about Ram using that pump as it had proven to have issues in prior applications from both Ford and GM in their heavy-duty diesel powertrains. Late in 2020, Ram made a change from the asymmetrical cam CP4.2 to a new symmetrical CP4.2, likely in a bid to solve some injection pump issues. 

For those that were hesitant to purchase a new Ram Heavy-Duty diesel because of the CP4.2, you can now rest easy as it looks as if RAM has rectified that for 2021. High Output Cummins purchasers will also be rewarded for their patience as Ram has made a few other changes resulting in a class-leading 1,075 lb. ft of torque, up 75 lb. ft from 2019 and 2020 models. Ram has also taken back to towing crown with a max tow rating of 37,100lbs when properly equipped. 

You can join in on the lengthy discussion on our forum here.