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DEF Head Failure

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Market moving (or not) to electric vehicles — Wayyyy off topic - interesting but off topic. Would love to discuss this , but please start a new thread for it.

Now back to the DEF hysteria…
 
Yep, DEF hysteria. I think Neal hit the nail right on the head. And if I get it, way more unknowns than knowns. But the beauty of this forum, it the exchange of ideas, i.e., you know a little, I know a little, this couple over there knows a little. Between the "littles" we might be able to formulate a course of action. I think I heave learned a lot more about DEF and it's associated issues herein then I might have really wanted to know. They say knowledge is power, and in this case I think that is entirely a fact.
 
This situation is an interesting one. A select group has a problem. They make the entire diesel landscape think it's a problem affecting everyone. It is not. Panic ensues. There is some interesting psychology as to why some do this, intentionally or not. If you step back and look at the facts of this situation it's a very interesting scenario. Makes you want to hoard toilet paper or motorhome parts!
 
We are buying extra foods which will disappear because of heat/drought out west. But you are correct, most of us will not have issues period. And not sure it makes difference, but for most part, using system as designed, I am getting close to 10.0 MPG routinely. Better than last coach for sure.
 
My understanding is that DEF is just Urea (also used in agriculture as a nitrogen fertilizer) and distilled water.

Quote... "Diesel Exhaust Fluid (DEF) is an emissions control liquid required by modern diesel engines. It is injected into the exhaust stream. DEF is never added to diesel fuel. It is a non-hazardous solution of 32.5% urea in 67.5% de-ionized water"

I wonder if you can just use a yardstick to mix up the DEF in the tank to re-dissolve any crystals?
 
Assuming you could figure out a way to stir the tank. I do not know if their is a "return line" if more is pumped into exhaust system or not. There was a cutaway posted someplace I will try to find it. Freightliner/Cummins does not seem to have the issue as do the spartan coaches, also think the systems are from different manufacturers. Again not sure.
 

All excellent article about the DEF head failure. All should maybe read, it will at least open your eyes further. If you are experiencing the issue, please note the Cummins contacts at the end and maybe a "nice and polite" e-mail to one of them might spur them on to request the waiver. Then they are doing the "software upgrade" not you the customer, and the ball is in their court. Yeah, lots of shop time, but, then your warranty is not compromised regardless of what process is taken. Just food for thought. DEF head is part and parcel of the pollution equipment required on unit. That system and it's associated warranty is very much different than the base warranty, as I believe it's 10 years and 150,000 miles, but do not quote me. I would have to look in my book.
 
As we await finalizing the purchase of our new to us 2018 Newmar Ventana, I am reading WAY to many forum threads and this DEF debate is consistently coming up. In my previous life I was an ASE Certified master automobile mechanic, now own a couple equipment rental stores and we do all of our own repairs. My question is, has anyone tried using something like this to get them back on the road when a debate hits? I will have access to a full suite of diagnostic tools with me that will come from my work previously, but this seems like cheap insurance to me unless I am missing something. OTR Reset Tool | Cummins
 
As we await finalizing the purchase of our new to us 2018 Newmar Ventana, I am reading WAY to many forum threads and this DEF debate is consistently coming up. In my previous life I was an ASE Certified master automobile mechanic, now own a couple equipment rental stores and we do all of our own repairs. My question is, has anyone tried using something like this to get them back on the road when a debate hits? I will have access to a full suite of diagnostic tools with me that will come from my work previously, but this seems like cheap insurance to me unless I am missing something. OTR Reset Tool | Cummins

So, I went and bought a small scan tool also. Not the cheapest, but I did not get an OE Cummins tool. When my coach set DEF head codes, it would not clear them. My coach would "correct" itself and show DEF level correctly after a short period, so I never had a derate. I do not know if once the system shows a derate if you could clear some/all of the data and at least get the ability to drive doing a countdown again? Unsure of that answer. And my coach was lost in a fire, so I never got to look into it any further. My replacement coach has not broke yet :)
 
As we await finalizing the purchase of our new to us 2018 Newmar Ventana, I am reading WAY to many forum threads and this DEF debate is consistently coming up. In my previous life I was an ASE Certified master automobile mechanic, now own a couple equipment rental stores and we do all of our own repairs. My question is, has anyone tried using something like this to get them back on the road when a debate hits? I will have access to a full suite of diagnostic tools with me that will come from my work previously, but this seems like cheap insurance to me unless I am missing something. OTR Reset Tool | Cummins

I don’t know if that will work or not, but I have never encountered a case of anyone being able to clear all the codes with scan tools available to the general public.

If you want cheap insurance, the DEF Sensor Simulator is your best bet IMO. I built one and I hope to never need it. DEF Sensor Simulator
 
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