Doc life span

[Rawze]

They get old and the chemicals in them DO wash out over time. Normal lifespan is about 500-600k if they don't get any coolant or oil intrusion.

Cleaning them with water or other liquids washes the platinum out of them fairly easily, weakening their performance each time you do it. 3 or 4 washes like you have done to yours, and it is pretty much toast. I have seen a LOT of people try that and later regret it. On a CM2250/CM2350 with NOX sensors, they start complaining about it via the rear NOX sensor usually, or they start using more and more DEF fluid.

As they get weak on a CM871 (no def fluid), the regen system starts to suffer and complain. DPF gets clogged up more often, and it is harder for it to get the DPF temp up during a regen cycle. As they wear completely out, well, you guessed it,.. repeated regen and emissions system problems with little to no explanation, as there is no NOX sensor(s) to report its lack of proper operation.

ANY TIME --- You get any kind of serious coolant intrusion in the system,.. BOTH the DPF AND DOC are almost always weakened greatly by it. 1 - 2 gallons through the exhaust can pretty much destroy them, weather it be all in one shot, or over a several month period.