Community Forums

freen03 · 05-06-2021, 08:22 AM

Are the DEF head failures happening on both the Freightliner and Spartan Chassis's

Ken C · 05-06-2021, 11:04 AM

Ours failed last week while we were in the Cochella Valley. Spartan sent a replacement overnight and Mobil Lube Express had a mechanic out the next morning to replace it. Great service from both companies.

tom chelbana · 05-06-2021, 06:51 PM

The DEF head problems are both FL and Spartan chassis. It is even across the complete HD DEF systems since 2016. In 2016 diesel engine companies were required to start testing DEF fluid for the correct fluid. This has turned out to be a big problem because the sensors for checking the DEF fluid have been sending incorrect information to the ECM and so the DEF head has to be replaced or engine will derate or stop running. Many HD trucks have this same problem at this time. Many use the same equipment for their DEF system.
Newmar Man

TUCSONRAIL · 05-06-2021, 07:06 PM

It seems more of a problem with Spartan than Freightliner. Just read some of the threads on the Entegra form. 3 years and no problems on my FL.

**Lt Dan** · 05-06-2021, 07:08 PM

It has also affected Tiffin's Power Glide chassis, primarily 2017-2019 year models. There have been others but the most were in that year range.

zman62 · 05-06-2021, 08:14 PM

Quote:

Originally Posted by TUCSONRAIL

It seems more of a problem with Spartan than Freightliner. Just read some of the threads on the Entegra form. 3 years and no problems on my FL.

It’s my understanding the def heads are manufactured by Shaw industries for both fl and spartan. It won’t matter what chassis you have

tom chelbana · 05-06-2021, 09:19 PM

One might think that Entegra are having more trouble with DEF but remember Entegra only built on Spartan chassis so they won't have FL DEF head problems. This problem is covering almost all HD diesel engines since 2016.
Newmar Man

Winepress · 05-06-2021, 09:24 PM

I saw Tom’s post about getting a extra def head to carry on the road. Makes sense, even though I have not had an issue on my FL chassis. Called Velocity and they said very few issues with def heads, so I ended up with a part number but no def head. Time will tell. It’s a Cummins item, I don’t think the part is different, except where it is mounted on the chassis.

Bchtravlr · 05-07-2021, 09:07 AM

Just replaced def head this week in my 20 MA. I thought I might avoid problems as we were one of the last coaches off the 2020 production line. Service center said it is happening on all FL and Spartans.

TUCSONRAIL · 05-08-2021, 10:28 AM

There are a lot more Freightliner Chassis out there than Spartan, yet most of the failures seem to be on Spartan. Maybe they got a bad batch or something. Just saying.

GW4607 · 05-08-2021, 02:51 PM

With Freightliner building over 65% of all Class A chassis across all lines you think Freightliner would have at least twice as many failures as any other chassis builder???

deaton · 05-08-2021, 09:04 PM

Quote:

Originally Posted by TUCSONRAIL

It seems more of a problem with Spartan than Freightliner. Just read some of the threads on the Entegra form. 3 years and no problems on my FL.

All Entegra’s are on Spartan, so to the extent you read about a Def head failure on an Entegra, it will be on a Spartan.

deaton · 05-08-2021, 09:09 PM

Went to the Diesel RV club rally at Distant Drums RV Resort in March of 2020. There was a Tech Talk on Def head failures. Of the fifty or so coaches there, about twelve reported Def head problems including me.

We took a poll. It was split with five on FL and seven on Spartan. I don’t know the split between those two chassis in the entire population, but I’m sure some of those coaches were not on either FL or Spartan chassis since we had a Prevost, a Newell and several other brands in attendance.

DSDP Jeff · 08-10-2021, 04:18 PM

After looking at my exhaust routing it seems to me that heat is a primary cause of the head/sensor failures. In our 2019 Dutch Star 3717 there is no hot exhaust routing near the DEF system. When you have a tag axle the routing seems to run right behind the tank. I still insulated my tank, and during every trip I hit my tank with the laser sensor to check the temp. Hottest I got was a 104 in the desert heat near Vegas. Well under the dreaded 120 number. I also like Newmar Man's idea of the vent to push outside air at the tank.