Need help on some DPF related issues.

New user. First post. Have lurked through threads over the last 3.5 years since becoming an O/O. I’ve always appreciated looking through the threads and reading through the dialogue in respect to whatever issues I had going on. Probably should have made an account 3.5 years ago, but here I am now.

I have a 2019 389 conventional day cab Peterbilt. I’m a rock hauler pulling a 37 foot aluminum Travis Wave Wedge end-dump trailer. Bought the truck with 416,000 miles. Currently at like 700,000 maybe? The mileage counter isn’t quite accounting for miles as it’s wonky and every time they hook up the computer it shows what I see on the dash, but I know that can’t be right, but I digress.

I’ve been having issues over the last 3 years with a lot as I cut my teeth with a used truck but specifically with the DPF and after treatment for the last 10 months. I recently baked off the DOC, DPF, and SCR. Gave me 2400 miles before it slipped back into “stop engine immediately” mode. It won’t hold the forced regen. So the mechanic running a diagnostic today said based on the codes to replace the exhaust gas differential pressure sensor. We checked the two lines to the ports and they weren’t clogged. We blew them out. I went and picked up the part and will have him install in the morning. Going to make sure he checks wiring for chafing or the metal inside isn’t worn. Also, check the connector for the corrosion or moisture, I suppose?

I just learn as I go when problems arise and just do what I gotta do to mange and correct things. It’s been a while ride and things are getting extremely tight. I’m inside of 15 months from having my truck and trailer paid off, but I’m holding on for dear life not to lose it. It’s tight as ever and I only ever live and operate on cash flow. So if my wheels ain’t turnin I ain’t earnin. No pity here just giving context.

I would love to delete my system but I just don’t have the 3500 to do it. Hoping I can either resolve the issues or just mange until I get the 3500 saved up. Sorry for the long winded text, but based on the codes do we really think new sensor is going to do the trick? I suppose we will install it, the software check for codes, try a force regen, and see what happens. The placed who cleaned my filters and such said the DOC failed but the mechanic says not so fast it’s still good. The Cummins reman is like 2500 so I’m just trying to roll with this current DOC filter. My fear is that it could be weak and needs to be replaced. Not sure if has ever been prior to me purchasing the truck.

Any opinions from anybody with experience would be greatly appreciated.

 

Hey, thanks for the reply and sorry for just now responding back. I replaced the DPF pressure sensor. Forced a regen that finally held after replacing the sensor. I’m still getting frequent calls for manual regens now that I’m back up and running. Like every 250 miles. I hope that number keeps climbing and the manual regen intervals are more spaced out. It’s a headache. I run locally about 35 mile radius. I’ll look to get some more info that the other member suggested. I’m just trying to get through this week after falling behind.

 

Thanks for the reply. Like I mentioned to Goody, I’ll be sure to get what info I can and update you guys. I’m just trying to get caught back up for the week after falling behind.

I’m swimming upstream against the current with this after treatment system and it’s wearing on me and killing me financially. It’s absolutely no way to run, and these dang mechanics never seem to paint me good picture with exactly how to resolve this. I’ll be sure to get the suggested information you guys mentioned, or at least what I can, and get back to you guys by Saturday 4/18/26. Thank you!