truck chugges at a low speed

This won't help you at all but my 2014 volvo is doing the exact same thing lately........ I believe my issue it that I am double the recommended hours for the initial overhead.

But I'm curious to see what others think about yours as maybe I'm wrong with mine.

 

How long as it been since either has ran a complete stand still regen? Paccar is the one motor I dont see a lot of but I do see regen issues with no engine light 5-6 times a week in all different models with all different motors. If you have the tools and such you should check the fuel pressure although its not likely since its not all the time giving you trouble but still a possibility. Also what toe of trans do you have behind it?

 

On my volvo it does passive regen, I think it just did one 5 minutes ago as the hot exhaust temp light was on when I stopped which Is usually how I know it's doing one.

In this one it won't let me force a regen unless it determine I need one, I am curious about the idea of it being a regen or emision issue as I have black soot covering my exhaust stack like much old pre emission trucks which is odd because it's a 14 with 100000mi on it. My local volvo shop doesn't know why.

 

Figures Volvo doesnt know. Could be a doser valve issue. You should be able to pull the doser off and look inside the exhaust and see if there is a bunch of def crystals piled up in your exhaust. If so your exhaust temp gets to low to ionize the def. And have you checked the def filter? There is a company that can bypass the regen on a Volvo although you have to be connected to the truck and internet. Also make sure no other drivers are cancelling the regen as this will cause the ECU to lock you out and you have to take it in o force a regen