By Russ and Tiña De Maris
If you’re stranded on the road, or afraid to leave home with a Cummins diesel-equipped rig, we have news. Last week we pointed out that Cummins didn’t make those diesel exhaust fluid monitoring (DEF) systems that have fouled up and even stranded so many RVers, but they could help with a solution. Since then we’ve been briefed on a possible workaround that might help some RVers.
We took out the list of corporate officers
First, though, a note on Cummins’ response to your communications to them. Last week we published a list of four Cummins executives (and their email addresses) who you might want to contact. Apparently many of you did, because by Tuesday, we got a pleading request from Cummins to, in their words, “take down or remove any names and emails of our leaders you have posted.” They asked we replace the list with one contact person in their organization. It was not an easy decision, and RVtravel.com staff kicked the request around. We finally decided to play ball with Cummins. Our thinking is that it is better for our readers to keep a friendly relationship with Cummins and, in doing so, trust that they will be more forthcoming with information that may be of use.
With that said, be aware that the same Cummins representative promised us that he could, “ensure that the leaders are made aware as appropriate.” The last two words of the statement are open to interpretation. We are hopeful that those of you who are caught up in this unhappy situation will be considered as valuable customers and truly in need of something other than a “We’ll see about it” attitude. Time will tell. Putting the list of executives – and possibly other influential Cummins’ insiders – back on line is not out of the question.
As far as an official position, Cummins was quick to send us a statement in robust “corporate-ese.” The critical statement buried in it reads, “We are also having discussions with our OEMs to consider other ways to mitigate this issue in an effort to best serve our customers, including potentially approaching the regulatory agencies to explore possible solutions.” Excuse us? Sounds a little bit like what we talked about in the last article – get a waiver from the EPA to allow a software patch that stops engine derating when the DEF systems go into glitch mode. RVers (and others) need real solutions today. Our possible workaround is coming – hang on.
“Having discussions,” sadly, often turns into more than a next day, next week, or even next month reality. Here’s our question: How safe do you feel tooling down the interstate in a Cummins-driven motorhome? If your engine derates, your speed dropping down dramatically below “freeway speed,” when you look in the mirror do you fear that oncoming 18-wheeler?
Here’s a statement Cummins asked us to print, and we do so, in full: “The DEF sensor failure prompts the engine software to follow a derate process mandated by law, which ensures that drivers are notified of the issue and are able to continue operating the vehicle safely for several hours.” Continue operating the vehicle safely? If your rig derates and slows down well below traffic speed, will Cummins hold this “safely” statement up in court when the first of the product liability cases are filed?
While Cummins and other OEMs are “having discussions,” our understanding is that the Environmental Protection Agency is having discussions of its own. We hope to have more to share with you next week. But OEMs should remember that old statement. “If Mama ain’t happy, ain’t nobody happy.” Our suggestion to Cummins and friends is, get yourselves out of “derate” and move on this quickly.
DEF head problems not limited to RVs
Now, as to a possible workaround. RVs and other over-the-road vehicles aren’t the only Cummins-equipped rigs having problems. We got a note from a gent we’ll call the Crane Man. His job is to keep a fleet of rental construction cranes up-and-running. Amongst his fleet, cranes with Cummins QSB 6.7 liter engines. Some of you may have something quite similar under the hood of your tow rig. About four years ago, his company started experiencing DEF head failures. Trouble for crane operators isn’t just a gradual derate. He writes, “Imagine a crane operator holding a 30,000-lb. load, and suddenly with no warning loses all throttle response.” Imagine being the workers down on the ground in the immediate vicinity.
As to when these DEF head problems arise – it’s not something predictable. A DEF head sensor failure can crop up at any time. Crane Man says he’s seen failures pop up on rigs with as little as 137 operating hours on the clock. Like the RV community, the construction equipment community is having the same issue with obtaining parts – they just aren’t out there. Interestingly, Crane Man tells us the manufacturer of the dead-head DEF heads is one Shaw Development. It’s a name familiar to many motorhome owners who’ve been stranded with DEF head issues.
Potential causes of DEF head failure
So what about a possible workaround? Crane Man’s theory on the cause of the DEF head failures is this: Motorhomes are a lot like rental construction cranes. These guys aren’t “daily drivers.” You take your motorhome out on a vacation, come home, park it. It may be weeks or months before you fire the rig up again. Same thing can be true for a rental crane. It could sit in the yard waiting for a call. Meantime, the DEF is sitting in the reservoir, breaking down over time. If poor quality or “late in shelf life” DEF was put in there, the breakdown issue is even worse. You fire up your rig, the potentially unstable DEF triggers a fault code, and the derate process begins.
How does this help you? We’ve heard three theories about DEF head failures. One is what Crane Man describes: Degraded DEF triggers sensor problems. Another theory, which we mentioned last week, is that poor engineering routes hoses right next to the microchips in the DEF head. The heat from the hoses essentially “fries” the chips. And finally, we have read a service bulletin from one manufacturer that suggests the heater hoses for their DEF reservoirs may have been mixed up. The engine coolant used to keep the DEF reservoir warm is being routed the wrong direction, causing a DEF sensor failure.
So here’s the possible workaround
If your DEF head failure is caused by “bad” DEF, or what the system perceives as bad DEF, you MAY learn something from how Crane Man uses a possible workaround. When the dreaded DEF sensor warning appears, his company pulls the DEF tank assembly out of the crane. Next, a tech removes the DEF head and sensor assembly from the tank. The old DEF is dumped, and the tank and sensor are “rinsed completely with distilled water”. The sensor is then put in a clean container and soaked in distilled water for about an hour.
When the time is up, the entire assembly and reservoir tank are reassembled. The reservoir is then refilled with clean, FRESH DEF. In July alone, Crane Man says they’ve done this to two of their rental units, and those sky-lifting moneymakers are back on the job, making money.
And, of course, the fine print
Now, here’s a major caveat on this possible workaround. Crane Man has the advantage of having the official Cummins diagnostic scan tool software (called INSITE). You can pick up your own copy for a cool $1,500. With it, Crane Man can clear the “bad” codes, and force the engine into an exhaust system regeneration. He tells us he “doesn’t have to wait for the code to clear on its own.” Does this mean that folks without access to the scan tool can do the “rinse and clear” trick and get away without resetting the codes? We’re not sure. We’ve asked Crane Man for his opinion, but haven’t received a reply yet.
Is this possible workaround something that might work for you? Clearly worth a try if you’re handy. If you don’t have the scan tool, and can still “do the mechanic-ing,” it could be worth the time to give it a try. We’d love to hear back from anyone who does give it a whirl. What if your skills aren’t up to the job? Then you’d need a cooperative shop willing to try. Of course, if they have the scan tool and software, that’s all the better. We CANNOT tell you that this will work for you – it’s a certified crapshoot. But if you’re stuck 1,500 miles from home with no clear idea of when your parts will come, it’s a “something to think about.”
Even if you’re happy, it may not last
Keep in mind, we know that even RVers who have been in the “happy” position of being able to get a new DEF head have had unhappy endings. New DEF head, and somewhere down the road – maybe not too far – and that dreadful DEF failure code reappears. All we can suggest is this: If you do get your system working, keep the DEF reservoir FILLED with FRESH DEF at all times. If you’re parking the rig for a while between trips consider this: Dumping the tank and refilling with fresh DEF before you head out again.
We can’t say much now, but we can tell you that there are moves underfoot that may offer another possible workaround. This workaround could work for folks whose DEF head issues aren’t necessarily related to bum DEF. We’ll let you know as soon as we can.