Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Vote for the Site Favourite ROTM winner for the year of 2021 HERE!
41 - 57 of 57 Posts

·
Premium Member
Joined
·
54 Posts
Guys 15‘s are not encrypted. Come on now. Where is all this crap info coming from? Lol

Either way a deleted truck will have “way” more soot than what I see in that picture. Not even a question now.


Sent from my iPhone using Tapatalk Pro
A partial delete, keeping the DPF will still have a clean tailpipe.
 

·
Premium Member
Joined
·
54 Posts
I guess it depends on the programmer. I think if one wants a delete, they delete all. If you have inspections, one may keep the dpf yet get rid of the high failing DEF. In Georgia, shops tend to delete everything, since we don't have inspection or testing on diesels. My friends 2015 lml came from Pittsburgh.
 

·
Registered
Joined
·
238 Posts
The only way I have noticed if it was done with care is to physically unplug the sensors. If it has been tampered with they are probably not plugged in all the way. Hope you figure it out as was mentioned before the fines and so on suck.
 

·
Super Moderator
Joined
·
1,724 Posts
Gentlemen, a reminder that discussing the details of performing any emissions delete is against the forum rules.

Rules are found at the link below:


If anymore detailed info is posted, I'll have to shut the thread down. Try to stick to the OPs original topic of why his truck seems to not be using DEF.
 

·
Registered
Joined
·
7,027 Posts
I've owned my 2015 for about 10 months and put almost 10k miles on it and some of that has been towing a 18k pound boat. I've never once had the DEF light come on and when I check the level through the DIC it just tells me level OK. I would of thought I would have had to add some by now, is it possible the previous owner could have deleted it?

The simple answer to your question is 'Yes, the previous owner could have deleted it'
 

·
Registered
2015 Chevrolet Silverado 3500 HC DRW 4WD
Joined
·
289 Posts
Discussion Starter · #46 ·
The simple answer to your question is 'Yes, the previous owner could have deleted it'
I will continue to use the truck as I have and assume its been deleted, I guess if it tells me its low one day I'll add some to it. I was just trying to avoid adding DEF if someone had previously deleted it. I just thought the new emissions were to difficult to delete, I suppose anything is possible.
 

·
Registered
Joined
·
7,027 Posts
I will continue to use the truck as I have and assume its been deleted, I guess if it tells me its low one day I'll add some to it. I was just trying to avoid adding DEF if someone had previously deleted it. I just thought the new emissions were to difficult to delete, I suppose anything is possible.
Does the DIC still show 'Exhaust fluid level ok'?
Below 30% it should change to xx%. It will switch to 'Low' if left long enough.

As it gets low, there will be 'miles to empty' warnings.
If it gets to where it thinks it's empty, there will be 'miles to speed limit' warnings.

Combined, you should have lots of advanced notice.
 

·
Registered
2015 Chevrolet Silverado 3500 HC DRW 4WD
Joined
·
289 Posts
Discussion Starter · #49 ·
Does the DIC still show 'Exhaust fluid level ok'?
Below 30% it should change to xx%. It will switch to 'Low' if left long enough.

As it gets low, there will be 'miles to empty' warnings.
If it gets to where it thinks it's empty, there will be 'miles to speed limit' warnings.

Combined, you should have lots of advanced notice.
Just says level OK as of now.
 

·
Premium Member
Joined
·
54 Posts
My theory on DEF level is fill the tank to full as soon as you get the first message. I used to wait until the mileage countdown. I have had 3 heater failures in 125k miles. The 4th is in now and I plan on keeping it closer to full and the heaters submerged in DEF. I guess it's not going to be a real test since I put a China assy back in.
 
  • Like
Reactions: Ron505

·
Premium Member
Joined
·
54 Posts
Gentlemen, a reminder that discussing the details of performing any emissions delete is against the forum rules.

Rules are found at the link below:


If anymore detailed info is posted, I'll have to shut the thread down. Try to stick to the OPs original topic of why his truck seems to not be using DEF.
My apologies!
 

·
Premium Member
Joined
·
124 Posts
This whole situation make absolutely no sense at all. If the emissions were fully intact and considering the miles the OP had put on the truck the DPF would be totally plugged by now unless it has been gutted. On top of that the second nox sensor would be going berserk and the check engine light would be glowing like the north start and the truck would have limped out long ago.

Not that this is a good idea (even though he no longer has any warranty left on the truck) if you really want to know go visit your local Chevy dealer and have the check what version ECM code is running on the truck. Also, you can take a vacuum pump and place a hose into the def tank to see if anything in fact is in it, another option you could also purchase and Edge monitor, with this you will be able to read the EGT temperatures along the way and if you wanted to force a regen that I bet it would not do. It would be a good thing to have either way just to keep an eye on everything.

Personally, at this point you have nothing to gain other then knowledge unless you are planning to sue the dealer your purchased from or force them to fix it. The code for the LML was broken long ago and from what I have read in this thread I have concluded the truck is in fact deleted, the DPF hollowed out and the code for the sensors has been bypassed or deleted. If there is a redeeming factor in this situation if you do have a deleted truck whoever did it really knew what they were doing and spent a good deal of time making sure it could not be detected visually and hopefully if it is truly deleted maybe they also got rid of the damn CP4 and put in a CP3. Good luck, keep up posted, you have my curiosity peaked.
 
  • Like
Reactions: RoboCop and Ron505

·
Registered
Joined
·
7,027 Posts
It could be def programmed out but still have a functioning DPF.
 

·
Premium Member
Joined
·
124 Posts
Knowing a good deal about the pieces and parts of a LML system (mostly because I had a 2013 and wanted to delete it). I seriously doubt just the def was programmed out. DEF and a properly operating 9th injector is necessary for the LML to complete a regen cycle. Failure to fully complete a regen cycle will result in a plugged DPF and limp mode. Without DEF the system WILL NOT go into regeneration which cleans the DPF.

One thing that is interesting that the OP posted is that in one of the pictures some soot it visible in the tail pipe. On a properly operating LML system the tail pipe tip is spotless and has zero black unless something is wrong with the system. For what its worth this is what the tail pipe looks like on a Duramax with a properly operating emission system should look like:

The OP's posted pictures reflects soot production, this would undoubtly illuminate the check engine engine light and message. I suspect the DPF is hollow and a very surgical delete has been performed. Otherwise this truck would have been limp and on the side of the road long ago. IMHO View attachment 1096230
Rim Automotive tire Gas Automotive design Circle
 

·
Registered
Joined
·
7,027 Posts
For what its' worth - I also doubt someone would go to the trouble of programming out def.
But it's possible.


Common misconception that so called the 9th injector is for def and also that def is for regen.
Both are wrong.

9th injector is for diesel to be injected during regen (to elevate the exhaust temps to burn out the soot)

There is also a def injector, that injects def upstream, anytime the engine is running.


DEF is to reduce NOx.
DPF filters out the soot. Regen combusts the soot.
LMM was a regen engine. It did not use DEF (because the permissible NOx emission levels were higher)

DEF is NOT required for regen.
 

·
Premium Member
Joined
·
124 Posts
I totally understand what the 9th injector is for, and true it does inject diesel fuel, BUT, it will not operate on a LML engine unless the ECM is satisfied there is sufficient level of DEF in the def tank. The DPF quantity is also checked to make sure it is good enough for the regeneration process to begin. Also the 9th fuel injector is located in front of the diesel oxidation catalyst (DOC) in the turbo downpipe. And will ONLY come on during a regen. It is true that the LMM engine did not use DEF and did use the 9th injector to cut down the soot level, and that is an interesting point, perhaps the previous owner figured out a way to use the LMM code in this truck?
 
41 - 57 of 57 Posts
Top