Fixing your DPF Problems in a nutshell...

[Waterloo]

You said the DOC and DPF were serviced, were you there when they installed the cleaned and baked cans? Did you visually inspect before they installed? You said the truck is fine with the exhaust disconnected, I wonder if they did not do the work you think they did, and just through the old cans back in. That is a common practice nowadays in many shops, even the big name dealerships.

When the cans were replaced, was the ECM reset using Insite?