cm2250 3375 2639

[Billdozer2]

There is another piece of Insite software that sole purpose is to test the aftertreatment system. I believe it is called DESA. I would download/install that to help with your diagnosis. You can e-mail Cummins for a free one year password to unlock the DESA software.

My truck set 3375 and 2754 (which is basically the same thing) a year ago. I pulled the DPF and cleaned it out myself.

My thread:
http://rawze.com/forums/showthread.php?tid=674

However, after cleaning, the codes came back the next day and the truck was regening every 50 miles or so. I gave up and figured I would send the truck to the dealer. That way I could rent a truck and continue working. The dealer cleaned the DPF again and flow tested it. It all passed. However, while they were running some tests and sending the info to Cummins, Cummins told them to replace the turbo, DOC, and DPF. I asked the service manager why did they replace those parts, his answer, because Cummins told us to.

Only reason I could think of is that something in the turbo was leaking oil down the exhaust. Shaft seal maybe? This contaminated the DOC and DPF, rendering them useless, even though the DOC and DPF flow tested fine.

My advice though, get that old style fuel pump off of there and get a new one ASAP. The old style pump is basically a grenade with the pin halfway removed bolted to the side of your engine block. If that pump fails, there is a good chance that the engine will turn to scrap metal. If the damage is severe enough, you can't even inframe it. Happened to another O/O I know. Punched a hole right through the block with less than 200k miles. Needed a complete engine.