FYI Good article on DEF head failures

[Rich-MLsRV]

I found this article very informative on DEF head failures

 

[Neal]

Great article, thanks for sharing.

 

[Old Bubblehead]

I especially enjoy the part that provides the email address for the folks in leadership at Cummins that don't want to petition the EPA for the RV community.

If you’d like to share your thoughts with Cummins management, here’s a list of folks at Cummins. We’re told they are all aware of the DEF sensor nightmare.

Vice Chairman: Tony Satterthwaite – [email protected]
Chief Executive Officer: Tom Linebarger – [email protected]
President and Chief Operating Officer: Jennifer Rumsey – [email protected]
Chief Financial Officer: Mark Smith – [email protected]

 

["EZ"]

Cummins can pass the buck all they want saying that they don't produce the DEF parts so it isn't their problem but here's the bottom line.............Since 2010 emissions laws were passed Cummins (and every other diesel engine manufacturer) can not sell their engines unless their engines pass the 2010 emissions. This means that without the DEF (or some other emissions solution) Cummins could NOT sell their engines. So, unless Cummins wants to stop selling
On-Hwy diesel engines they are responsible to make sure that the DEF system is working. BTW..........Caterpiller chose the wrong technology and couldn't meet 2010 emissions so they DID have to stop selling On-Hwy diesel engines. I can't see how Cummins can say this isn't their problem with a straight face. The Federal Government says differently. Also, if this isn't Cummins issue then why did they spends hundreds of millions of dollars to develop the DEF system so their engines would meet the new 2010 emissions? It wasn't Spartan that spent the research and development money it was Cummins.

 

[Neemer]

I especially enjoy the part that provides the email address for the folks in leadership at Cummins that don't want to petition the EPA for the RV community.

If you’d like to share your thoughts with Cummins management, here’s a list of folks at Cummins. We’re told they are all aware of the DEF sensor nightmare.

Vice Chairman: Tony Satterthwaite – [email protected]
Chief Executive Officer: Tom Linebarger – [email protected]
President and Chief Operating Officer: Jennifer Rumsey – [email protected]
Chief Financial Officer: Mark Smith – [email protected]

The General Counsel needs to be on that list. That’s the person holding the reigns.

 

[TJ&LadyDi]

I found this article very informative on DEF head failures

Well-written article with an excellent explanation of the issues involved. I was unfamiliar with this publication, but have now made a “contribution” to it and will be a regular reader. I invite anyone who also discovers this publication through this article to join me in doing that.

TJ

 

[Neal]

After thinking on this a few hours, I'm not sure I'm on board this is a Cummins issue. Or more specifically, it's not their responsibility. Cummins provides the "leads" for the sensors, starters, etc. Take the case of TJ's engine shutdown issue. Is that a Cummins problem or whomever attached the components to the engine such as the Chassis manufacturer?

In the case of the DEF system, Cummins has the engine and after treatment configuration. The DEF tank and DEF sensor, who owns this? Cummins or the chassis vendor? Cummins has the interface for the sensor to talk with the Cummins system but the sensor system could be outside their boundary of responsibility. This is why in hindsight, after reading the article which puts blame on Cummins, I'm not sure I agree in the end. Thing through everything that attaches to the engine and see if all of that falls under their responsibility.

 

[TJ&LadyDi]

After thinking on this a few hours, I'm not sure I'm on board this is a Cummins issue. Or more specifically, it's not their responsibility. Cummins provides the "leads" for the sensors, starters, etc. Take the case of TJ's engine shutdown issue. Is that a Cummins problem or whomever attached the components to the engine such as the Chassis manufacturer?

In the case of the DEF system, Cummins has the engine and after treatment configuration. The DEF tank and DEF sensor, who owns this? Cummins or the chassis vendor? Cummins has the interface for the sensor to talk with the Cummins system but the sensor system could be outside their boundary of responsibility. This is why in hindsight, after reading the article which puts blame on Cummins, I'm not sure I agree in the end. Thing through everything that attaches to the engine and see if all of that falls under their responsibility.

Well, to be clear, these kinds of issues are a study in finger-pointing! I have asked Newmar, Spartan and Cummins who is responsible for correcting the engine shut-down issue we are experiencing. The clearest answers I have received to date are (1) “it depends” and (2) “we don’t know, but it isn’t us.” When pressed on the “it depends” answer, none of the three could (or would) provide an answer to “What does it depend on?” This is frustrating, to say the least.

As to the DEF head issue, I didn’t feel the article author “puts blame on Cummins.” Rather, he says an argument can be made that since Cummins selected the DEF solution, spec’d the equipment to be used to resolve its emissions issue and controls the related software, it should also be responsible for helping resolve the current DEF head problem with a software patch.

Personally, I think that is a reasonable expectation. And, I think the same “reasonable expectation” could also be laid at Newmar’s door since it selected the K3 chassis as the only choice for the Mountain Aire line. Last in line is Spartan, in my estimation, since they had no choice but to use the emission control equipment spec’d by Cummins and don’t have the choice of using the software “patch” unless Cummins provides it.

YMMV

TJ

 

[CaptainGizmo]

This reminds me EXACTLY of my “argument” of the cruise control and engine brake issue! Talk about the run-around!

 

[Buly]

I wander if the military diesel vehicles are under the same EPA air pollution rules like the civilian ones? It will make them less reliable in combat if they are using the same DEF equipment.

 

[TJ&LadyDi]

I wander if the military diesel vehicles are under the same EPA air pollution rules like the civilian ones? It will make them less reliable in combat if they are using the same DEF equipment.

My guess is that military vehicles don’t use DEF at all; just one more thing that would have to be delivered to the battlefield.

TJ

 

[Just George]

Has anyone found info on DEF failures in the trucking industry? My thinking is there must be other engine manufactures in trucks running a lot of miles. So if there is failure info it would be interesting to see if they all (or majority) are associated with a Cummins engine or if the def failure issue is affecting others equally. If the commercial trucking failures are heavily weighted to configurations with Cummins engines then perhaps some focus on trying to get Cummins to engage for some help would be in order.

 

[Neal]

I'd love to see real numbers, not sentiment or emotional analytics.

 

[TJ&LadyDi]

I just did some research on trucks having DEF head problems and found very little information. It doesn’t seem like many truckers are having this issue or, at least, are not posting comments about it.

Interestingly enough, I found quite a number of different trucker posts extolling the Cummins ISX engines as being pretty trouble-free. Many of these guys are running them for 500K to 1M miles plus without complaint. That doesn’t seem to be true for motorhome drivers, however! So, are we (a) not taking proper care of our Cummins engines, (b) more prone to worry about and comment on DEF head issues, or (c) both of the foregoing? Hard to know.

It does seem that the DEF head problem is a bigger issue for us motorhomers than it is for truckers. Could if be simply that Cummins is prioritizing trucks in the parts supply chain because they are considered an essential part of the commerce system? Who knows? My guess, however, is that if you are a big OTR truck outfit, a way will be found to get you the parts needed to keep your trucks running.

Nothing earth-shattering here, but the bottom line seems to be that we’re hearing a lot more about DEF head failures in the motorhome community than are being heard in the OTR truck industry.

TJ

 

[Neal]

I tried finding info too and was unable. But let's step back for a minute and realize some major differences. Truckers have engines in the front with high airflow and front mounted radiators. I assume their DEF and after treatment configurations are also up front with ample cooling. Motorhomes have the engines rear mounted with much poorer airflow and cooling. When I was at Cummins (Tucson) I asked about the different motorhome engines and their reliability, the guy said the 605's run very hot which can be problematic. Just not enough cooling for them. Now let me discount that statement with the very same situation we get with asking "techs" about tire pressure, etc. - we get opinions and a gazillion answers, so who knows what to believe. But I digress, let's keep in mind huge differences between motorhomes and truckers - engine location and cooling of the components.

 

[redbaron]

The theory that I have seen others discussing is that temp has nothing to do with the real issue. Instead, the amonia created by temp is causing the shaw (and other) sensors glue to fail, allowing the sensor to become compromised. The failure is the sensor assembly itself, causing the sensor to fail. Once the sensor fails, the report will be one of the data points reported by the sensor, or all of them...temp, quality, quantity. This will cause a derate.

Replacing the sensor, and making no other changes will resolve the issue. No need to regen. No need to drain/fill. No need to do anything other than send good signals.

 

["EZ"]

I wander if the military diesel vehicles are under the same EPA air pollution rules like the civilian ones? It will make them less reliable in combat if they are using the same DEF equipment.

They are exempt. Or at least they were.............

 

[Rich-MLsRV]

RVtravel.com posted an update - Stranded due to DEF head? New developments and a possible workaround.

 

[Neal]

Interesting revision. I don't think getting some EPA approval and a bypass is the long term fix, or any fix for that matter. This sounds like an engineering and design problem for those experiencing this more than others. "Crane Man" in the 2-3 paragraphs outlined some probable causes which I hope will gain attention that this could be a problem caused by a poor design by a vendor instead of the system itself.

 

[Sonic]

I would classify a valve that’s “prone to stick” as a substandard implementation of the Cummins design. Asking Cummins to develop a software patch and install it on potentially hundreds of thousands of vehicles isn’t the right approach, and I can’t blame them for resisting. It sounds like chassis manufacturers need to pressure their vendors to implement more robust solutions, then issue a recall to replace these potentially problematic units.
Interestingly I read a comment from the CEO of NIRVC who did a parts search across all of his service departments nationwide, and found 65 DEF Head assemblies ordered over an 18 month period. 64 were for Spartan chassis, 1 for Freightliner (they use different vendors for their DEF head assemblies)
That’s just one data point but it would be interesting to see if it would hold up across all service centers.