DEF head problems

[kengardner]

Hi, I know there are some posts about DEF head problems but I'm still confused. It seems like there were a number of EPA requirements that caused the DEF head problems in certain year Diesel engines. I believe 2013- 2016 had a change and 2014-2019 had another change, ?? Are the problems more frequent in the smaller Cummins engines like the ISB 360 hp ? Was there a change on the 2020 up years or did the problems get corrected ?? Can anyone shed some light on the worst years for these problems ? I am shopping but do not want to have to sit in the new motorhome in my driveway because I am afraid I'll break down in timbucktoo. Is there a way to tell by mileage used whether the problem is more likely to occur ?? I see a lot of used motorhomes for sale with very few miles on them. I always thought a used automobile suffered from sitting long periods of time ( dried out gaskets, tire rot, etc ).Are diesel pushers better to have some miles on them ( 30,000 - 50,000 for a 7 year old rv ) ?? HELP !!! I am trying to get a recent ( 2015 -2019 model ) but am nervous about this since I read of folks not being able to get replacement parts. Thanks, Ken

[R.Wold]

Originally Posted by kengardner

Hi, I know there are some posts about DEF head problems but I'm still confused. It seems like there were a number of EPA requirements that caused the DEF head problems in certain year Diesel engines. I believe 2013- 2016 had a change and 2014-2019 had another change,

Problems up to 2015 have primarily been the level sensor (float) failing by reading empty when the tank is full.

For 2016 the “def quality” sensor was added and that seems to be the worst offender, although some 2016 coaches will be on 2015 chassis without the quality sensor


?? Are the problems more frequent in the smaller Cummins engines like the ISB 360 hp ?

The same issues affect all Cummins and most other diesels with DEF. There are many ISL, ISM, and ISX diesels powered coaches with the same issues. Its the DEF management and delivery system - not the engine. In most cases DEF warranty issues fall on the chassis manufacturer, not engine.

Was there a change on the 2020 up years or did the problems get corrected ?? Can anyone shed some light on the worst years for these problems ?

Freightliner claims to have solved the problem and from reports Ive seen, as well as my own experiences, this appears to be so, but I wouldnt be surprised is someone with a 2020 or later FL coach says they have had issues as well. A lot depends on external factors such as DEF temperature and condition.

Spartan and some Tiffin chassis (Powerglide?) can be expected to still have problems. They use the Shaw Development def head and are on gen 7 - we’ll see how that goes.

I am shopping but do not want to have to sit in the new motorhome in my driveway because I am afraid I'll break down in timbucktoo.

This is apparently a successful project and a good insurance policy for Spartan and Tiffin coaches. I think someone nas adapted it to Freightliner as well but Im not certain about that: https://defsim.myervin.com/def-senso...or-quick-build


Is there a way to tell by mileage used whether the problem is more likely to occur ?? I see a lot of used motorhomes for sale with very few miles on them.

Milage has nothing to do with it. Some coaches have problems around 1500 miles, some at 35,000.

I always thought a used automobile suffered from sitting long periods of time ( dried out gaskets, tire rot, etc ).Are diesel pushers better to have some miles on them ( 30,000 - 50,000 for a 7 year old rv ) ?? HELP !!! I am trying to get a recent ( 2015 -2019 model ) but am nervous about this since I read of folks not being able to get replacement parts. Thanks, Ken

There is no special year or milage to help you make this decision. And to make matters worse, there is the DPF issue (easier to manage but causes derates) and DEF pump and doser failures to add to your miseries. Lower milage is always nice, but in this case, higher milage vehicles are going to be better proven and have more bugs worked out.

Your best bet is to educate yourself on these systems so you can do a good job of carefully managing and caring for them (they are fragile) and get good maintenance records so you can see what has been done and when. If the dealer wont provide records (they usually dont) the chassis and coach manufacturers can provide a lot of info based on the VIN.

[kengardner]

Thanks for the great info R.Wold. I'll study it some more. I personally would prefer to go pre 2013 but DW would prefer brand new. Fortunately we are not in any hurry. Ken

[R.Wold]

Originally Posted by kengardner

Thanks for the great info R.Wold. I'll study it some more. I personally would prefer to go pre 2013 but DW would prefer brand new. Fortunately we are not in any hurry. Ken

I went through a period of emissions frustration with my 2016 and was looking at coaches with pre-2008 emissions - specifically was swayed by a 2009 Monaco Bishop, 40’, 500hp, tag, 2007 emissions - gorgeous but it sold immediately. Since then Ive learned enough about this stuff that I could deal with a newer coach just fine. But DEF has been mandated since 2010, so a 2013 rig will have some of the potential problems as well - just not as much as 2016 and later.

I also used to covet the Spartan chassis for half a dozen key features unique to them, but given their emissions problems and their stubborn refusal to dump Shaw products, I wouldn't touch one until I was sure they finally have this sorted. At the very least every Spartan chassis should come with a spare DEF head, and both manufacturers as well as Tiffin (Powerglide) should extend their emissions warranties to 8 years like Ford, Chrysler, GM, and Mercedes.

The other thing to get control of is DPF system. It can be managed to keep it trouble free so you can enjoy long maintenance intervals, but not without a good understanding of how it works and what it needs. The dealers don't tell you this stuff either because they either don’t know, or they think they'd scare you off with all the ways these rigs can leave you stranded.

[kengardner]

We are looking at ordering a 2022 Entegra Accolade 37k XL. I haven't seen any mention of problems with the 21 models yet. It'll take about 2 months to get one which will give me more time to learn if Freightliner has solved the problem or not. Yikes, this whole DEF head problem would make the new Ford 7.3 gas engine models look better. I'm wanting the exhaust brake for mountain driving so I've only been considering diesels so far. Ken

[Dutch Star Don]

The DEF head issues have been more of a problem with newer versions around 2016 - 2017 and newer. Just in the past few weeks, the EPA has finally issued a software bypass of the DEF system sensors until the issue is resolved with a final repair. Freightliner has had a much smaller issue with DEF head sensors as compared to Spartan using Shaw DEF heads.

I know many like to say they're not buying a new coach because of DEF issues, I think there are more reasons than that! As the years roll by and new coaches become old coaches, the majority of used coaches will all have DEF or DPF.

DEF head issues will get resolved in the not so distant future. The big issue now is supply chain issues. Truck chassis manufacturers want the issue fixed too!

[Fiesta48]

Luckily I've got a 15 Freightliner chassis, so far very reliable at almost 50k miles.
But this won't stop me from considering the new Ford Godzilla engine to get rid of the complexity and expenses of diesels. There are about 50+ inspection, oil and lube points on a Diesel. Maybe 20 on a gasser. 6-7 qts oil versus 6-7 gallons.

[Ray,IN]

I am under the impression all emissions systems are required to be warranted for 100,000 miles per EPA rules/regulations.

[move on]

No. A new Ram diesel emissions warranty is only 5 years.

[R.Wold]

Originally Posted by Ray,IN

I am under the impression all emissions systems are required to be warranted for 100,000 miles per EPA rules/regulations.

FL and Spartan are 5 years 100k miles. However Ford,Chevy and Mercedes have extended their emissions warranties to 100/8 years. I thought Chrysler did too. Or maybe they are 80k/8 years for federal emissions components. So far nothing from Freightliner or Spartan on such ethical considerations.