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Doc life span - joed2323 - 11-22-2016
Just a few questions regarding the doc life cycle.
Im curious if my cummins dealer does this correctly.
Normally you can send in a dpf to get baked, sometimes it passes sometimes it doesnt with there testung procedures "aka machine"
Ive cleaned docs before with a long air gun and or water. I look thru it with a flash light... Yup looks clean good to go.
I asked my cummins dealer how do they test them?the service tech said they just blow them out also. But I asked them about the life span on them, and they looked at me like I was talking in some "mumbo jumbo language" and said thats above their heads.
I asked them about the "special metals" or platinum coating and asked them well this has to get washed out eventually, and he looked at me like wtf
Can you just keep cleaning the doc repeatedly like cummins states? Buying a new dpf and using a doc that was cleaned out 2-3 times is ok?
You think they would just want to sell more parts and make more money and tell me, docs only last so long and then you gotta replace them just like any other filter.
Gettin these dpf filters baked to me is a crock of crap, especially when you turn in a coolant soaked dpf filter and they call and tell me your dpf is cleaned and ready to go...ok wait what, plus when the dpf has been forced regened umpteen times.
I know a doc is basically a catalytic converter, but is their anything else I can look for in the doc to actually know I have a good working doc before I stick it back on a truck?
The first few replies will be remove the mandate, trust me I would love too but the place I work for will never ever do it.
RE: Doc life span - Rawze - 11-22-2016
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.
RE: Doc life span - jimeneztrans84 - 11-22-2016
What's a good mileage interval on the dpf and doc? If you replace them before the check engine light comes on do you have to still reset?
RE: Doc life span - joed2323 - 11-22-2016
What would hour wise length life span be on these,?
Miles do not apply out here
Our trucks get serviced 350 hours give or take +/-35 hours. Cummins specs these motors at 800 hours per service, but that seems way too long, especially since they classify us as a heavy haul application
High idle time. What would or how long would one guestimate a healthy life span on a truck serviced hourly with piss poor milage, lucky to have 1-200 miles in a 14 hour shift. Easily 8 hour pto time per 14hour shift
Thank you rawze for responding, I appreciate your input, tell it like it is no sugar coating... Again thank you for what you do.
I am learning every day on this forum thanks to many on this forum
Sometimes I wish I was asking for more input on after removing the mandate.. Give time, wouldnt that be awesome. Again prob never happen. So im stuck in this repeated loop of hopelessness and sh$t
Thanks again for any input. I'm always learning from this forum.
Thanks again
RE: Doc life span - jimeneztrans84 - 11-22-2016
So y does Cummins recommend cleaning or replacing dpf at 200k?
RE: Doc life span - EricB - 11-22-2016
Cummins recommend cleaning after 200k
RE: Doc life span - EricB - 11-22-2016
Cummins recommend cleaning after 200k. I guess they calculated that after 200k the ash load gets too high.
RE: Doc life span - Dcolumbia - 11-22-2016
Buddy just blew a turbo on his dd15, which I do think has a better life span than the Cummins system does, at 800,000 miles. I asked if he cleaned the filter and doc, said that he had no oil in the exhaust side. Lasted two weeks, sitting in the shop now with oil soaked dpf and doc temps that won't go over 365 degrees. 4900$ later he will be back in the road tonight with a new doc and dpf filter. So how long is the life expectancy? Until you start having problems. There are set intervals you should service them in a perfect situation but let's face it, these systems fail more often because of other system failures like egr, turbo egr cooler, dozer nozzle failure. They are too costly for the o/o and are killing them left and right. I will never own a truck with a working aftertreatment system again. Just my thoughts.