The first years of the cummins ISX commonrail engine had major issues with the ceramic plunger failure. The worse case scenario would be you replacing the commonrail pump and overhauling your engine with a repair/parts bill in the upward range of 30k.

So as the majority of the trucks have had the plunger and barrels swapped out by now there is still quite a few trucks I work on that have had the ceramic plungers in the pump. I am surprised that the drivers or owners of the trucks do not know anything about the plunger failure recall.

Once the issue was known cummins produced a barrel plunger kit with a steel plunger to replace the old ceramic plunger design. They also have an updated tappet kit that replaces the older Obsolete Brass Tappet Roller Pin with Diamond-Like Coated Tappet Roller Pin. This kit covers CM2250 and CM2350 isx engine reeplacement parts. There is only one difference between the cm2250 and cm2350 plunger and barrel assemblies, which is their thickness of the hex head on the barrel assembly. The thinner hex fits the newer cm2350 and the thicker hex part fits the older cm2250 engines.

Here are the part numbers you will need for each model type, you will need 2 of each part number if you upgrading:

CM2250

Barrel and Plunger: 4327258

Tappet: 4359134

You can purchase this kit from the link below:

CM2250 Tappet and Barrell/Plunger kit

CM2350:

Barrel and Plunger: 5406130

Tappet: 4359134

Please contact me with any questions you have around this or other issues you are experiencing with your Cummins engines so we can get more content out to help others and help you with your issue.