Forum Discussion

class8hauler's avatar
class8hauler
Explorer
Jul 23, 2015

Diesel Particulate filters

Is your DPF diesel particulate filter, giving you issues? I have been an over the road truck
Driver for many years. I use my truck to hall my 40 ft 5th wheel on the weekends. It seems that just about everywhere I go I meet RV'ers who are just now discovering what a DPF is and how it relates to there engine issues. I usually end up with several owners hitting me with all the typical questions on why there truck shows hot exhaust gas Temps and DPF issues.
As truck drivers we have had to deal with this newer technology on a daily basis since late 2007. The cost of repair and maintenance of this could be used in a Visa commercial, Priceless!
For the weekend warrior, these components may not have been any concern
For the 1st year. Now that you have a few miles and some extra idle time on them you are starting to discover what Regen issues are, and plugged DPF. Since I have been dealing with this for 8 years already I can offer help by way of proven solutions that will keep you out of the shop and on the road. Don't worry, most mechanics know less than you do about preventing these problems.
Rusty
Class A
  • class8hauler's avatar
    class8hauler
    Explorer
    Jul 26, 2015
    Sensors and DPF units getting plugged up is result of collecting soot from fuel. Diesel only burns about 82% complete, the remainder is soot that is dumped in the oil and out the exhaust. Several companies make fuel catalysts which causes diesel to burn closer to 99% complete. I have tried a couple over the years, some work better than others. By having my diesel burn up to 99% efficient I do not get plugged filters or sensors. 1 way I can tell is my oil analysis shows my soot level between 0 and 1. There are a lot of other ways I can tell, but never needing a Regen or a DPF cleaned is the most important.
  • GMandJM's avatar
    GMandJM
    Explorer
    Jul 24, 2015
    Great to read you are back on your way.

    Let me know how the warranty issue works out for you as it looks like we would be in the same boat if the DPF fails on our coach.
  • YC_1's avatar
    YC_1
    Nomad
    Jul 24, 2015
    Back on the road now. Fortunately they credited the $688 cleaning charge on the one that was bad and with the Cummins Power Club card I received a 10% off on parts and labor.

    Out the door was $3200. Not including the tow charge that was covered by Coach Net. A real shout out to them. Nothing but great things to say about them.

    They updated my computer to the newest version firmware so that was worth some. It apparently changes some things with the regen process.

    One of the filter sensors had failed and was causing the system to regenerate improperly.

    The Cummins dealer in Albany New York went far beyond outstanding customer service. We spent two nights in their parking lot plugged in to 50 amps.

    I know a couple of technicians missed lunch getting us back on the road in two days. The receptionist was amazing and supportive. She called my extended warranty company a couple of times.

    I have not completed the discussion with the warranty company. The repair clearly shows the issue was caused by a sensor which is covered. Hopefully they will agree.
  • class8hauler's avatar
    class8hauler
    Explorer
    Jul 24, 2015
    Ok, so if you read this article from the trucker paper http://www.trucknews.com/features/a-dpf-dilemma/
    My answer and the answer from your mechanics may make more sense.idont think off road fuel would make much difference.
  • GMandJM's avatar
    GMandJM
    Explorer
    Jul 24, 2015
    YC 1 wrote:
    The issue started right after refueling at a tiny mom and pop station. I'm wondering if they got some crappy fuel or maybe some off road fuel?


    That could be it. If the fuel wasn't low sulphur, it could cause problems. And since you you were on a road where you couldn't get up to regen speeds, your system went into LHM (limp home mode).

    Thanks for the heads up about DPF (and presumably EGR) not being covered under extended warranty because they're considered exhaust. That didn't even cross my mind.

    Does your engine have an EGR cooler? Just curious.

    I was really hopeful The DPF Whisperer could have gotten everything fixed for you. ;)
  • class8hauler's avatar
    class8hauler
    Explorer
    Jul 24, 2015
    I've got to get rolling for the day. Do yourself a favor and take 10 minutes to read this story from the CEO of Bison transport on there DPF issues. http://www.trucknews.com/features/a-dpf-dilemma/
  • class8hauler's avatar
    class8hauler
    Explorer
    Jul 24, 2015
    Yea, remember, they are in the fix it business, that's why there are so many in the trash. Diesel only burns about 82% complete in our motors, the rest turns to soot. This is why your oil looks dirty right after you change it. We have never had a catalytic converter Aka DPF in our exhaust to catch it before. Now that we do all that soot is being captured and plugs up the sensors and DPF.
  • YC_1's avatar
    YC_1
    Nomad
    Jul 24, 2015
    class8hauler wrote:
    Ok, so is this the 1st issue you have had with this system? If I use a 15 minute warm up in the morning, and same as a cool down at night, and some time at the fuel pumps, drive 10-11 hours mine usually shows about 15% idle for the day. So keep that in mind for your situation. prior to the lights coming on and going to the dealer were you on a long drive, long idle, what was the scenario?



    Wow, that does not seem like a high idle time. I do not drive anywhere near those hours. Three to five hours a day is enough. I leave it idling during fuel stops which don't take long in the truck lanes.

    I wonder if the IDLE thing means time between engine runs. I only have about 35K miles in 7 years so do not drive long distances.

    The issue started right after refueling at a tiny mom and pop station. I'm wondering if they got some crappy fuel or maybe some off road fuel?

    It tried to regen right after that but we were on small winding roads and just could not get up to highway speeds. Hindsite I should have pulled over and and run it up.

    Based on their metal recycle bin I am not the only one who has had issues. There were several filters in the trash.
  • YC_1's avatar
    YC_1
    Nomad
    Jul 24, 2015
    class8hauler wrote:
    It is legal to run with a cracked DPF, most older class 8 tractors are cracked. They just won't clean them. A sensor may be blocked and asking for a Regen even though the rest of the system does not require it, and in that case it won't do a Regen on its own.


    Unfortunately it takes my 08 Cummins into a limp mode eventually due to the blockage. They cleaned it so there should not be any back pressure. They claim one of the sensors failed as well.

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