Aftermarket DOC/DPF

[MH89]

I’m guessing most people here will say aftermarket DOC and DPF are not good? I’m looking at a Dinex DPF and Skyline DOC which I can get both for around $3,700.
Just not sure if the quality of those is decent and how long it’ll last me. I’m at 750k miles, bought the truck when it had 450,000, and not knowing its past history - I’m not sure they were baked/cleaned.
Would at 750k miles now be even smart to bake them since theyre so old, or would aftermarket be better?
And no - I am not spending $10-12,000(maybe more) on OEM doc and dpf, that’s not very financially responsible.
I have already replaced the IMAP and exhaust gas pressure sensors.
Will be replacing the EGR and DPF differential sensors too. All of the sensors I replace are OEM, I don't go aftermarket on those.
Will also be taking apart the intake manifold and cleaning out all the pipes, spent some time last night watching Rawze’s videos on that.

But then there is still the dark option: deleting the whole thing. I’ve spent last few days reading all about it, and seems like a lot can go bad if you delete, so I am really not sure if I want to go that route.
If I can install the aftermarket DOC and DPF, all the OEM sensors, EGR tune up, then I’m hoping it’ll get me to a million miles +
I have also never gotten an overhead tune up done, will definitely be doing that as well.

[mikkhh]

Provided that you live in a place where it is legal solving those problems for once and all would be the go to choice.

I highly reccomend to buy scan tool (inline-6 from china works fine OR genuine nexiq that costs many many times more) to read fault codes, reset derates and read programming by yourself.

If you already have scan tool you can pull the programming and send it to somebody who can take a look and maybe can sort things out.
https://rawze.com/forums/showthread.php?...5#pid72945

Instead of aftermarket DOC and DPF I would have old original ones baked clean.

Pull the egr cooler and wash it (or use compressed air to blow it clean). DPF doser valve may need replacing too since it has 750 000 miles on it.

[Rawze]

(10-15-2025 )MH89 Wrote:  I’m guessing most people here will say aftermarket DOC and DPF are not good? ...

Waste of moneys!.. I have seen them plenty, and they have half or less of the precious metals in them (why they are cheaper).. and do not operate correctly, and act up like mad./.. and are nothing but a regret of moneys in the end.

[mikkhh]

Has somebody tried aftermarket dpf and doc on newer trucks that have Particle Matter sensor? I am afraid that those aftermarket ones are going to give faults almost instantly.

On older stuff that do not have PM sensors aftermarker DPF s may "work" with constant regens and so on, but no fault codes and check engine lights. Constant regens cause increased fuel consumption and increased engine wear.

On cars and trucks that have DPF s wet cleaned (permanently damaged) ALWAYS get sooty tail pipes and white smoke out of exhaust, that is unburnt diesel, on cold startups. Yet even dealerships around where I live promote that kind of equipment destruction. Even truck dealerships (yet manuals on manufacturer's website tell that there are only two dpf service strategies - dry clean OR replacement). Seems like nobody cares anymore. There is no pride in doing things the proper way or fixing stuff.

Dealerships around here are quite honest, sometimes they openly admit they have no idea what they do and just are going to randomly throw parts at machine until it is fixed. Of course customer will pay for everything and if not fixed need to pay for redoing everything, another diagnostic fee and so on.

To somebody in foreign country with high sulphur fuel. DOC s and DPF s and SCR catalyst will react with sulphur and create acid rains. That is why there demandetes are necessary.

[MH89]

(10-16-2025 )mikkhh Wrote:  Provided that you live in a place where it is legal solving those problems for once and all would be the go to choice.

I highly reccomend to buy scan tool (inline-6 from china works fine OR genuine nexiq that costs many many times more) to read fault codes, reset derates and read programming by yourself.

If you already have scan tool you can pull the programming and send it to somebody who can take a look and maybe can sort things out.
https://rawze.com/forums/showthread.php?...5#pid72945

Instead of aftermarket DOC and DPF I would have old original ones baked clean.

Pull the egr cooler and wash it (or use compressed air to blow it clean). DPF doser valve may need replacing too since it has 750 000 miles on it.

The originals are 750k, youre telling me baking them now would be better then installing new aftermarket doc/dpf? I’ve replaced the 7th injector and doser last year. I dont know about the other solution - reading some threads here - even things like getting them drilled can go wrong. I’m pretty good with technology type stuff and can follow directions so the technical side of this I can maybe do myself. I would have to invest Neqix and a legit Cummins insite or?

(10-16-2025 )Rawze Wrote:  

(10-15-2025 )MH89 Wrote:  I’m guessing most people here will say aftermarket DOC and DPF are not good? ...

Waste of moneys!.. I have seen them plenty, and they have half or less of the precious metals in them (why they are cheaper).. and do not operate correctly, and act up like mad./.. and are nothing but a regret of moneys in the end.

I ordered both of them and they should be coming in a few days, but I can still return them. Would you say at 750k to try baking the originals or join the sith side? I’ll follow your lead Yoda, just tell me what to do.
I’m basically trying to do preventive maintenance since I feel like I’m at the mileage where I’ll be getting constant issues on the emissions side of things, have already started with fault codes whenever I go on the road recently.
I did take pictures of all the data while 30-40mins into a forced regen that I had to do last week, tried to put me in a derate. Maybe I can send it to you somehow and you can look at it and see if anything looks off? I have a Ancel HD3400, so no Neqix/Insite type program on a laptop

(10-16-2025 )mikkhh Wrote:  Has somebody tried aftermarket dpf and doc on newer trucks that have Particle Matter sensor? I am afraid that those aftermarket ones are going to give faults almost instantly.

On older stuff that do not have PM sensors aftermarker DPF s may "work" with constant regens and so on, but no fault codes and check engine lights. Constant regens cause increased fuel consumption and increased engine wear.

On cars and trucks that have DPF s wet cleaned (permanently damaged) ALWAYS get sooty tail pipes and white smoke out of exhaust, that is unburnt diesel, on cold startups. Yet even dealerships around where I live promote that kind of equipment destruction. Even truck dealerships (yet manuals on manufacturer's website tell that there are only two dpf service strategies - dry clean OR replacement). Seems like nobody cares anymore. There is no pride in doing things the proper way or fixing stuff.

Dealerships around here are quite honest, sometimes they openly admit they have no idea what they do and just are going to randomly throw parts at machine until it is fixed. Of course customer will pay for everything and if not fixed need to pay for redoing everything, another diagnostic fee and so on.

To somebody in foreign country with high sulphur fuel. DOC s and DPF s and SCR catalyst will react with sulphur and create acid rains. That is why there demandetes are necessary.

Well if the aftermarket DOC/DPF will give me issues like fault codes and more regular regens, then I dont think I should install them. Both of them were $3500, and Im guessing theres a reason theyre cheap, but here I am thinking it might be better to install new aftermarket filters then baked 750k mile filters?

[tree98]

SEND'EM BACK!!!!!!

Either

have them baked at a dealer with the proper cleaning/testing equipment or buy new genuine OEM.

OR

Have the engine demandated by someone recommended on this site.

There is no third option that makes any sense at all.

[MH89]

(10-16-2025 )tree98 Wrote:  SEND'EM BACK!!!!!!

Either

have them baked at a dealer with the proper cleaning/testing equipment or buy new genuine OEM.

OR

Have the engine demandated by someone recommended on this site.

There is no third option that makes any sense at all.

Looking at $640 restocking fee for them, I done goofed

[mikkhh]

I have experiences with cheap aftermarket catalysts on 10-30 year old gasoline cars that get yearly tested for HC and CO emissions from tailpipe readings. Well on most cars you do get check engine for catalyst efficiency faults if you use aftermarket catalysts, emissions you can pass first time after installation, second year usually those catalysts are done and they need to be heated up big time to pass emissions test. Original catalysts on the other hand last long long time some even 10-20 years before emissions failures, usually they get damaged due to engine consuming oil. when cars have gotten old. There are buyers who buy used catalysts to harvest precious metals out of them. Most buyers do not want those aftermarket catalysts for even free. OEM catalysts have still scrap value on some old japanese cars that are 30 years old might have a catalyst that is worth 1000 bucks by catalyst recyclers.

It makes sense to use those cheap (50-100usd) crappy aftermarket catalytic converters on 500-1000 bucks beater cars (and if those crappy catalysts fail you do not pass yearly inspection emissions wise, but can still drive) not on commercial equipment that your income depends on. Some guys just buy aftermarket catalyst and make quick attachment with clamps so they only use them for emissions testing.

How much extra fuel frequent dpf regens cost you? Extra fuel used is money lost and since truck is driving every day costs to add up over a year quite fast.

[hhow55]

I had mine cleaned and baked at about 750k miles and problems persisted........You would be wise to either replace with Oem, or Delete. And if you delete make sure it's someone officially recommended from the forum. Plenty delete Butchers out there.