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Discussion Starter #1 (Edited)
So, this is 4th DPF cycle in a row, where I have exceeded 500 miles driven at or before 40 grams of accumulated soot.





Whats going on thats different? I tried using this Liqui Moly DPF Protector additive.


I'm not a big believer in additives, but a friend had good results with this stuff, and suggested I try it.

Its supposed to increase combustion efficiency, lower soot production, increase cleaning efficiency and a bunch of other claims.

Does it work? I'd say.... YES.

Ive driven this truck for over 100k miles, and have a good understanding of its behavior and regen cycle intervals.

I usually get between 350 and 450 miles between regens. 350 being nearly all city miles, 450 being about a 50/50 mix. Regens start at 43 grams, count down to zero, then rapidly climb up to 12 or so, then the cycle behaves pretty normally until the next one starts.

For 4 cycles in a row, the minimum miles driven at or below 40 grams is 500 miles. The highest miles before a regen was triggered was 608 and it had not reached 43 grams yet. I believe mileage alone triggered it.
This cycle is majority city driving... 70/30

The regen cycle itself lasted aprox 1 mile driven , for every gram of soot... 43 miles for 43 grams as an example. Regens are now shorter by about 4 miles or so.

The real kicker is when it counts down to 0 grams, it counts up to 5 grams fairly quickly, then counts up normally from there. It used to be 10 ( or more) grams.....

The DPF back pressure is lower too. At 40 grams at freeway speed, it's measuring 1.02 psi. In the past at this gram level, it would have read 1.5 to 1.75 psi...

Having this happen for 4 cycles in a row , starting with the first usage, makes it more than a fluke. Something is making a difference.

All these truck behave differently, but I've seen other members report the quick run up to 15 grams or so right after regen. If you are experiencing this, this might be worth a shot....

I'd make a good stocking stuffer......
 

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Discussion Starter #2
Never said it would clear out a plugged up DPF. All I said is it ( appears) to make my emissions package function better.

Same truck, same usage, same fuel from the same Chevron station, no maintenance done, nothing except this additive..... and a noticeable change.

Your mileage, may vary......
 

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Great suggestion with some real world experience. I might have to try that one myself. Where do you find that product?

Btw, don’t let the trolls get to you. It was obvious by reading your WHOLE post that you were not talking about a clogged DPF.
 

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Discussion Starter #4 (Edited)
Where do you find that product?
Rock Auto. 1 can to a full tank, filled right after the regen cycle is completed.Then drive and fill up as needed until the next regen cycle.

Its about $8.

https://www.rockauto.com/en/moreinfo.php?pk=10939185&jsn=1437&jsn=1437

I am not endorsing this stuff... I'm as critical as most anyone here on snake oil type stuff... just relaying my experience which so far has been good.

https://pim.liqui-moly.de/pidoc/P000035/5148-DieselParticulateFilterProtector-40.0-us.pdf
 

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Subd.

I have always used fuel additives of one brand or another but never a DPF specific product. My thinking it is a high cetane product, making the fuel burn hotter, a hotter exhaust temp the less soot it creates. Time for some research. I see from their website it is available at your local auto parts joint.
 

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I protected my DPF too............It is in the rafters of my shop safe and sound,never collects anything but dust :wink2:

On a serious note, at $8 (roughly about 3 gallons of fuel) a tank, have you ever tried calculating the amount of fuel saved and compared its cost to the the cost of the additive to find out just how much money it is actually saving you?
 

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Discussion Starter #8
On a serious note, at $8 (roughly about 3 gallons of fuel) a tank, have you ever tried calculating the amount of fuel saved and compared its cost ....
I look at it this way.... 500 miles / $8 = $0.016 per mile to try the stuff out.

I'm driving to San Diego today (about a 90 mile loop) I'll see if there's any kind of MPG improvement and report back.
 

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I look at it this way.... 500 miles / $8 = $0.016 per mile to try the stuff out.

I'm driving to San Diego today (about a 90 mile loop) I'll see if there's any kind of MPG improvement and report back.
There is yet another thing to consider as well. If you have an LMM like I do then reducing the regens is beneficial to the longevity of the engine by reducing the washing of the cylinder walls with that raw diesel.

Honestly, that was the strongest reason I can think of for that DPF to fall off. When first I got an LMM I intended to keep it bone stock. Then I learned a bit about he engine and its regen process and was appalled at the manner in which it functioned.
 

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I’m no chemist, but the moly is a high temp lubricant that bonds to metal. It may be coating the metal in the dpf so it captures less soot.

Any one else notice tap-a-talk running real slow?
 

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……………………………………………………………………………………………………………
You bunny-wabbet murdering monster - have you no sympathy for all those cute little fuzzy-chinned bunny wabbets you are killing with that "deleted" truck of yours...?

I am holding YOU personally responsible for the end of human life here on Planet Earth in 10 years, because YOU did that nasty thing to your truck's equipment.

And another thing...have you no sympathy for the oil companies? Do you realize what would happen to their sales & profits if everyone who owns a diesel did what you did...tens of millions of gallons of diesel fuel that would not need to be processed, transported, and burned.

I am reporting you to that lovely congresswoman from Brooklyn (AOC), She'll know what to do with you.
:surprise:
 

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Discussion Starter #14
So, here's how things went today.

I forgot I was close to a regen, so when I gassed up I mistakenly added the DPF Protector stuff. I have not had it in the system during a regen before.. and I hit the road. The regen started about 30 minutes into my drive.

It was the shortest regen I've ever had..... 31.7 miles. This was all freeway, 75mph continuous.




Fuel mileage? I once compared the DIC to hand calculating it, and it was close with the DIC adding a slight overerage to the mileage.


This was on the return trip, 75 mph the whole way, windows up, A/C off... 21.7 mpg over 87 miles. This is about normal, just maybe a tenth or 2 tenth's higher but within what I would expect so it's hard to make any definitive statement regarding mileage.

So there you have it..... I'd be very interested to see if others have the same experience.
 

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You folks are kidding yourselves if you think any "MOUSE MILK" is going to solve the problem of a DPF that is starting to get stuffed up; that doesn't "clean" properly...that the re-gen cycles are increasingly closer together.

I like how you still use the term mouse milk, in quotes no less despite having actual real world lab results showing that additives work. every time i read your posts like this i hear "WRONG WRONG WRONG FAKE NEWS" play on repeat in my head.

The solution is simple...my best guess is a maximum of 100,000 mile intervals - I think, but am not certain, that is what the big OTR's accept.

glad we cleared that up lol

All over the country in every major city are shops that take the DPF's and clean them PROPERLY. That means they are cut open, PROPERLY cleaned out, welded back together, so that they can be installed where they belong.

Just accept the fact that it isn't that easy for those of us with "consumer grade" vehicles. Sadly, our DPF's are part of the exhaust system...meaning the first time you want to get them cleaned, you have to find a shop that will cut them out of your truck, and then re-install them after they are serviced. I believe I paid $650. for that service.

yes, however based on your own experiences reported on this forum this process is at best a gamble. If there is a product that can positively impact the life of the emissions system that sounds like something people who cannot delete would like to know about.

Don't let your DPF go to the point where the intervals between re-gens are starting to get close together - at some point in time your truck's computer will do to you what mine did to me on a grade, while towing...on a rainy night - shut you down into "LIMP MODE" which means a speed of about 7 mph. Not fun on a crowded Interstate.

that is not accurate. Your truck will never go from normal operation to 7 mph limp mode at once unless there is some actual hardware failure. The system is designed with gradual speed reductions over the next ~1000 miles if the issue is not fixed. At the end of that, after being stepped down multiple times before it finally restricts you to idle speeds. So i suppose if you ignored the warnings all over the dash for a 2-3 tanks of fuel then sure, your stuck at 4 MPH

Yes, the GM shop procedure is to try a "forced delete". That means running your motor without "load" for about an hour - GM insists that wont hurt your truck - personally, having some background in engine servicing.....running a motor without a load at higher rpms for any length of time is just plain abuse. A proper cleaning by a professional cleaning service, not a "forced re-gen"....(which don't solve the problem of a stuffed-up DPF for very long) is the answer.
i think you mean forced regen, not delete. Id love for GM to do forced deletes. the DPF needs to be hot to get it to regen, and if its plugged up its goign to be hard to get that to happen, so elevating the idle to increase exhaust temp, flow, and pressure makes sense to me, though i agree that this is a BS solution to the problem. I dont see what harm running the engine up to 2K or so will do without load on it. How is that harder on it then running at 2K on the highway with a trailer on the back? Your not going to get valve float at that speed so theres really no risk to the engine so long as there is sufficient air flow to keep if from over heating.
 

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I have been using a product called Better Diesel FBC (formerly Enerburn) that has produced similar results. These products are fuel borne catalyst that lower the combustion temp of soot which makes passive regen happen at lower EGTs.
@6686L is right in the sense that eventually the DPF will reach a point where it needs to be taken off for manual cleaning. This is because the ash produced by soot burning stays in the filter. I think using additives like Liqui Moly help to delay that need and keep the engine running better and more efficiently by extending time/mileage between regens. I am currently gathering data to estimate if it is cost effective to delay the manual cleaning by using the FBC.
Thanks to @AlisoBob for the thread keep the post on your progress coming.
I am curious (I currently have an 17 F250 PSD)
What triggers the regen process besides soot load in Duramax (time, mileage)?
And is the trigger different between engine generations (LMMs and up have DPFs right?)?
What monitors do most use to view PIDs?
 

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Discussion Starter #18
What triggers the regen process besides soot load in Duramax (time, mileage)?

What monitors do most use to view PIDs?
The Duramax regen is triggered by a comparison of miles driven, gallons burned, exhaust back pressure and maybe elapsed time.

An interesting update is I continued to get 500 miles of driving at or before 40 grams of soot for 3 more cycles....

Then last week I intentionally skipped adding the stuff after a complete regen, just to see what would happen. The next cycle delivered 425 miles at 40 grams and the regen started at 445 miles at 43 grams. This was about 50/50 city / freeway driving.

This cycle I put the stuff in and I'm at 395 miles at 33 grams. I will make it to 500 miles before 40 grams.

I know this seems like a snake oil infomercial... but to me, the stuff works.



The monitor I have is the Edge CTS2. It's awesome .
 

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The Duramax regen is triggered by a comparison of miles driven, gallons burned, exhaust back pressure and maybe elapsed time.

An interesting update is I continued to get 500 miles of driving at or before 40 grams of soot for 3 more cycles....

Then last week I intentionally skipped adding the stuff after a complete regen, just to see what would happen. The next cycle delivered 425 miles at 40 grams and the regen started at 445 miles at 43 grams. This was about 50/50 city / freeway driving.

This cycle I put the stuff in and I'm at 395 miles at 33 grams. I will make it to 500 miles before 40 grams.

I know this seems like a snake oil infomercial... but to me, the stuff works.



The monitor I have is the Edge CTS2. It's awesome .
having similar results,I was regening at 385-400,started using the moly and I hit 500,then 525 both at 44grams of soot.what kinda stinks,is that it regens down to 5-8 grams.all viewed by cts2.
 

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Gentlemen,

I know no one has responded to this post in 2 months, but i have a new interest in DPF equipped trucks. I am in my 3rd week of owning a '20 2500HD, this is my first truck with a DPF as i came from an '02. In my '02, the dreaded injector eating LB7, i was religious about using 3.5 oz of PFFP in every tank. In the 440+k miles i drove the truck, the factory injectors were replaced at 199k miles and when i sold the truck the second set were doing great with over 240k miles on them. I am a believer in additives, if there is proof it actually performs as advertised.

I am interested in what AlisoBob and Work Truck Fanatic were saying about the two additives they discussed. My truck has right at 2k miles and i've had 2 regens, about 800 miles each. I was wondering if i started using one of the two additives mentioned if that would keep the health of the DPF in its current state? I would like to hear from each of the gentlemen if they are still running the additives and if they are still seeing the advantages of doing so.

Thanks,
-Mark
 
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