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I dont think it will be that easy, as if the NOX sensors where operating and the system was gone it would show a code, you have to trick you way around not only the system but the diagnostics which is in a completely separate part of the code to the control system.
Your comments make me laugh. Seriously!
 

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Your comments make me laugh. Seriously!
I attended many seminars when this was being considered and most of the discussion was around preventing tampering and what to do if the DEF ran out. There was a lot of effort put into tamper proofing and diagnostics that is encrypted into the core code. While it may seem easy to delete it, to make it work properly and not cause issues is very difficult.
 

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I attended many seminars when this was being considered and most of the discussion was around preventing tampering and what to do if the DEF ran out. There was a lot of effort put into tamper proofing and diagnostics that is encrypted into the core code. While it may seem easy to delete it, to make it work properly and not cause issues is very difficult.
It may not be as difficult as you think. Man made it and other men can hack it.
 

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So lets look at it this way- from what @s022mag is describing the truck LOOKS like it is unaltered, but has towed and traveled well far enough that it SHOULD have needed def added a couple times at least, and he has not added any. It would take a fair amount of work to do it, but I wonder if it has had the dpf and other exhaust components removed by opening up the canisters and removing the guts from them, and putting them back together to give it the appearance that it is unaltered?
The reason I bring it up, is because there is a gentleman local to me that does fabrication work that did that on his early LML purely for the fact that it would APPEAR to be a stock unaltered truck, but not have any more issues with def or dpf
 

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So lets look at it this way- from what @s022mag is describing the truck LOOKS like it is unaltered, but has towed and traveled well far enough that it SHOULD have needed def added a couple times at least, and he has not added any. It would take a fair amount of work to do it, but I wonder if it has had the dpf and other exhaust components removed by opening up the canisters and removing the guts from them, and putting them back together to give it the appearance that it is unaltered?
The reason I bring it up, is because there is a gentleman local to me that does fabrication work that did that on his early LML purely for the fact that it would APPEAR to be a stock unaltered truck, but not have any more issues with def or dpf
Exactly my thinking to the T. But he should be able to hear a rumble coming out of the tail pipe that would be suspicious of it being messed with.
 

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Discussion Starter · #26 · (Edited)
DEF is used about 3%, so assuming you are getting 6 mpg towing that heavy load for 10,000 miles that is 1600 gallons of fuel and 50 gallons of DEF, the tank is not that big. Someone has messed with your truck and never told you, bad bad news.
According to the DIC I get around 10-12 towing, and I've only towed about half of what I've put on the truck if that, not that it makes that much difference and the truck runs fine as if nothing is wrong, so explain the bad bad part to me?
 

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Discussion Starter · #27 ·
How is this something you don’t notice when buying a vehicle?
Explain how you would check to make sure the DEF is in working order before you buy a truck? What's it even matter. I asked a simple question on wether not DEF could be deleted and I haven't got one answer except that someone has messed with the truck and I'm screwed. Which I can't figure out why yet, because the truck runs fine, tows fine and hasn't yet cost me any DEF. So before you start labeling me a idiot, maybe you can post something a little more helpful, after all I thought that is what this site is for.
 
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It may not be as difficult as you think. Man made it and other men can hack it.
Anything is possible with time and $$, but I know enough about digital control systems to realize that this is tough nut to crack properly. Any numnuts aftermarket can make up something that might work, run a couple of tests and make up some BS marketing, but to have it perform well over a long time, not damage the engine and still not trigger alerts is not easy.
 

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Discussion Starter · #29 ·
Here are some pics of the exhaust and def tank. I didn't get all the way under to take pics cause I didn't want to get snow all over my clothes.
Tire Wheel Hood Automotive tire Car

Tire Wheel Automotive tire Automotive lighting Hood

Tire Wheel Automotive tire Hood Automotive lighting
 

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You definitely pass the visual inspection. Do you have any idea where your vehicle was registered prior to your ownership? Def looks like you have some soot built up inside your tailpipe though.

Have you noticed any loss in power at any point or lag in drivability? When you can, i would suggest getting a close look at your DPF canister and see if any of the welds appear to be done after production. Maybe previous owner gutted the DPF and eliminated DEF entirely.

Still haven't answered a big question though - do you have any exhaust note or able to hear the turbo through your tailpipe? This would be the biggest tell tale sign of elimination
 

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There are two separate systems on these trucks a DPF and a SCR which uses the DEF, I think the photo is of the DPF which is normally downstream of the other. The SCR will have sensors and an injector assembly for the DEF and is normally quite close to the turbo. The photo of the tailpipe is a good one as a proper operating diesel today tailpipe should be basically spotless as is the one in the photo.
 

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I dont think it will be that easy, as if the NOX sensors where operating and the system was gone it would show a code, you have to trick you way around not only the system but the diagnostics which is in a completely separate part of the code to the control system.
My coworker has a deleted 15 lol. No def ( tank is gone), no egr but still has the particulate filter and nox sensors. You can see them on the scanner. Just no codes for nox, egr or def. I saw it last year helping him with his 9th injector and regen. I'm still stock, so we got to compare both.
 

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Explain how you would check to make sure the DEF is in working order before you buy a truck? What's it even matter. I asked a simple question on wether not DEF could be deleted and I haven't got one answer except that someone has messed with the truck and I'm screwed. Which I can't figure out why yet, because the truck runs fine, tows fine and hasn't yet cost me any DEF. So before you start labeling me a idiot, maybe you can post something a little more helpful, after all I thought that is what this site is for.
Nox1 will be higher than nox2. If nox 1 and 2 are close to the same no DEF. The purpose of the DEF is to lower nox.
 

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My coworker has a deleted 15 lol. No def ( tank is gone), no egr but still has the particulate filter and nox sensors. You can see them on the scanner. Just no codes for nox, egr or def. I saw it last year helping him with his 9th injector and regen. I'm still stock, so we got to compare both.
Nope. Darmah59 clearly stated that the feds have it locked and encrypted. No one can crack the code! And hes right yanno. Its not possible to tune out the flux capacitor on these things anymore
 

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Nope. Darmah59 clearly stated that the feds have it locked and encrypted. No one can crack the code! And hes right yanno. Its not possible to tune out the flux capacitor on these things anymore
He clearly thinks so. If only he knew. LOL
 
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Discussion Starter · #36 ·
According to the carfax this was a one owner truck used for commercial/business. Most of the history records are in NY with regular vehicle emission inspections performed. Last one was 1/10/20 with 131k miles on it. It says it was performed that's it. Then in was traded in possibly on 11/14/20 with 134k miles and then I bought it in March of 2021.
 

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Discussion Starter · #37 ·
My buddy had a 2015 for a few years and he used it just for towing and said it hardly used any def. He has also owned a 18' or 19' and currently owns a 2022. He said the new ones use a lot more for some reason.
 

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Nope. Darmah59 clearly stated that the feds have it locked and encrypted. No one can crack the code! And hes right yanno. Its not possible to tune out the flux capacitor on these things anymore
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.


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According to the DIC I get around 10-12 towing, and I've only towed about half of what I've put on the truck if that, not that it makes that much difference and the truck runs fine as if nothing is wrong, so explain the bad bad part to me?
It's starting to sound to me like you're lucky lucky.
 
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