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Heads up information related to SCR/DEF on ISX15

I thought everyone might be interested in some information that I've found out about the ISX15 in the 2012 KWs, not sure if the following is true for other model trucks with this motor as I have only been talking to two people I know who have a 2012 KW T700.

Both friends have been having severe issues with their DEF/SCR system causing problems, including two or three derates each. They've spent the majority of this year so far in the shop.

My one friend finally got tired of the problem, drove it to his local dealer and told them "I'm not picking it back up until you can tell me why this keeps failing" and then called both corporate KW and Cummins to let them know what was wrong and get some help getting the problem fixed.

My other friend got in touch with a contact at the KW in Green Bay (should tell you who we're lease purchasing trucks from) and they have been working to resolve his issue.

Both kept getting DEF/SCR codes indicating the system needed cleaned.

One found out that the three heated supply lines to the system have an active recall on the parts, however his VIN has not been released in the recall campaigns (they've only released 2 of 3 sets of VINs) but he was assured his VIN will be in the last set of VINs.

The other found out his SCR Catalyst was bad and this is a known issue for this truck so much so the part has as many as 70 on back order. His small KW in Terre Haute told him they do about one replacement a month it's such a common issue. He was told however, this does not seem to be a recall issue, yet. He has been working with the regional service manager for his shop (I believe he covers IN, IL, WI, MI)

Both had work done on this system that was erroneously billed as non-warranty work so they are both having to try and get reimbursed for the funds they were charged.

I'm posting this to let anyone may be having similar, frequent, issues know which direction they may be able to point a shop in.

These systems should not fault out that often so if they keep doing it, there is an underlying issue. A few of the shops my buddy with the bad catalyst went to just followed their flow charts that told them to clean the system and sent him on his way. He broke down less than 48 hours later in one case of this happening (was the final straw). Also, if a component of this system fails during the power-train warranty, it should be covered by the warranty.

I'm not sure how they managed to figure it out, but my friend with the bad catalyst, the dealer was able to determine it was bad without any fault codes. This may be due to the fact that he get the regional service manager involved and he required they actually troubleshoot the issue not follow the flow charts they're required. I'm not sure and my friend didn't ask.

They've both lost a lot of revenue due to this system failing on them. Hopefully this info will help save other people some time and money if they're having the same problems or start to experience this system faulting/derating.

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Good info for sure. Not sure how Cummins is involved other than that being the engines in these particular trucks.

I have a 2013 Freightliner with a 2012 ISX15. If you look at the ID plate you'll see on most they have "Delegated Assembly" on the tag. I questioned a few Cummins techs and emailed Cummins about it. The response I got was the engines are built without all the SCR/DEF and DPF. Its the manufacturers that are choosing and installing their choice of systems.

I do know that there is a ECM recall on the 2012 ISX15. If they haven't had that done they might want to. It's a update. Seemed to help out in overall throttle response. Did not change much else that I noticed.

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That could prove to be informative that the manufacturers are doing the DEF/SCR system not the engine manufacturer. He hasn't been told this by anyone he's had service done and he's been talking to both Cummins and KW about it.

I do know one of them got the ECM update recently, didn't seem to help with the issue.

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I think we are still learning how to drive these trucks with SCR. I would like to propose an idea. Is it possible that because of our lack of knowledge of how the system works that we (drivers) might be operating these trucks in a manner that might cause problems? It is possible to generate problems with the filter media if we shut the truck off while in the middle of a passive regeneration. It would affect both the DPF filter and the SCR. When the fuel is cut off during the regen process, the filter media super heats past the melting point, collapsing the filter media pores. Same when the DEF is being injected during a burn off of NOx.

Another issue to consider is starting up a cold engine. I understand that we are all concerned with idling, but it is possible that not idling the engine for a few minutes might be causing the SCR system to have problems? The SCR does not work when the exhaust gasses are cool, causing the DEF to just blow down on the filter media and react with the precious metals it is made of. Over idling will cause excess soot in the DPF, but that is what it is made for, collecting the soot. 3-5 minutes of idling won't really cause that much soot to clog the DPF filter. It will allow the exhaust gasses to raise up to a burnable temp for the SCR system.

Last, all of these engines have a barometer somewhere on the engine. A barometer is kinda fragile and is a known issue to DD and FL (and they are not telling anybody) If your barometer is broke, you will have MPG problems as well as massive soot build up in the DPF and possible destruction of SCR filter media.

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I will say that my buddy was told by the ISX engineers at MATS last year that it runs the turbo through a pre-spool. He noticed that when he first starts the truck after shutting it off that it sounded different and his boost was a little higher and after a few minutes it settled back down. He also noticed that if he did not allow the truck to complete this his fuel mileage was hurt. I definitely think you might be onto something in that we may not know exactly how to operate these newer technology trucks but things like the pre-spool and any other situations need to be mentioned to drivers. I know I wouldnt have time to sit there and read the entire manual to see if there were any differences in a new truck versus an older truck. They may need an information sheet that details these kinds of things.

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Yes they do this. It makes the truck unbearable to drive in city traffic. It cuts the acceleration down and makes downshifting a nightmare. You have to rev the engine so much higher than usual. I wished they said why they do this.

I think there's more to these DPF/SCR systems then we understand at this time. This is not a new concept. It's been around since the 80's just not in our industry.

http://en.wikipedia.org/wiki/Diesel_part...

I think it's a combination of lower RPM engines and old driver habits that cause most issues. I never shut my truck off during a regen or when it's doing the above mentioned pre-spool. It's doing this for a reason.

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Nor does he, he also doesn't move the truck until the pre-spooling is complete.

I think you're right about the old driver habits. You also have the drivers who were never taught to warm the motor up or let it cool down before and after driving. I see a lot of the newer guys, even when I started 6 years ago, that fire up the engine and drive away and as soon as they stop, they cut the motor off.

Another problem with some of the older model engines, if they were doing a regen at highway speed and you had to get off the interstate, the RPMs would not stay high enough for it to properly complete the regen. I noticed that a lot when I drove a DPF truck, it'd always want to start the regen not long before I had to get off the interstate and it wouldn't complete because the RPMs were too low.

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I have a 2013 pete 587 with the isx15 and I love it. The big companies detune these engines and cause a lot of trouble. I went to diesel Dr in effingham Il had him reflash the ECM with factory 550hp 2050 lb/ft torque and this thing runs amazing. I get up to 8.8mpg and stay over 7.8 90% of the time. If I stop the truck and get the high heat warning I know it's regening and I park and hit the switch so it finishes its regen. Seems to work very well. I never liked the idea of stopping it in the middle of a burn. Seems harmful to me

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I have a 2013 KW T800 with a 550 ISX. I keep the regen switch in the off position all the time. When the ECM wants to regen I then have the choice of when to let it start. My main reason for this is so that the truck doesn't start a regen while parked in tall grass, I transport construction equipment. A friend of mine burned his truck down for this very reason. By leaving the switch off you have better control of where, when, and know how often your system is regenerating. My one annoyance is sense the last ECM update I am now derated until a regen is started. ARGGG!

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Hey Your. (thats showing up as your name,lol) Can you tell us which ECM update version dreates until you regen? I'd like to use your mention that makes more sense than these IDIOTS design the updates. Thanks

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I have isx15 450 hp my truck has code (scr/def service required) for about a year, the check engine light it on, but no problems. cummins,kw don't seems to help me, what can i do to fix it?

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that's my problem,just started tonight .I've changed the def filter about thirty thousand miles ago costly little bugger too! 2012 kw w900 550 cummins

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I have a 2012 Peterbilt 386 ISX15, currently in DSU Peterbilt here in Portland Oregon. Same issues as already discussed except I have a back pressure issue and now a compression issue in the motor after bringing my last load here (2300 miles) from the last shop I was at in Denver for the same issue minus the pressure issues. All I can say is warranty doesn't mean much on these issues. DEF/SCR/DPF systems aren't considered for full coverage in the drivetrain warranty. Not sure why this is, but the only have warranty on certain parts of the systems. If when you were to first get the check light, stopped, and got it towed I don't think the other components not covered would be so damaged. But let's face it, if you own yours like I do, paying a towing bill is very steep and more than likely you're going to keep going till you find a dealer and deliver your load. Enough with the warranty crap, let's go to how to drive an emission controlled diesel engine. These systems were created for best case scenarios. The world is quest case scenario. The system works fairly well if as stated above you have your ECM points set correctly. The biggest problem with most of your company trucks if the fact that they have turned most of your settings down, which causes an unstable environment for complete regeneration. Then you have to look at idling the vehicle below its factory settings which creates uncertain deposits from the mid grade compression of the fuel. You then have the automatic shutoff that can be bypassed with a high idle setting, again passing unstable nox into the system at 8-10 hour increments a day. More buildup and most trucks are blocked from doing a regen in high idle. Then as stated earlier you also have the turbocharger variated pressure to aid in helping push out low nox fumes till the engine equals out to specified levels for the regen system to operate. Most of the drivers in these trucks don't know about listening for engine sounds to tell you when to do something, so they are now just creating a ticking time bomb as to when, not if, the system will fail. Also getting the catalyst filter cleaned every 100k miles helps to reduce pressure issues and keeps the system running cleaner and as close as it can to optimal levels. Mine was cleaned 92,500 miles ago, only minor build up/deterioration on the catalyst itself. And that's why I am here now because I bought my truck used and have had similar problems before. When I get this one fixed this time I am putting the programmer in it to turn up fuel/air mix and hopefully create a better environment for the system to operate. Miss my old truck without all this headache.

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I recently suffered some health problems that took me away from my sweet sweet cinnamon and my beloved [a 2012 t660 studio, and the trucking industry]. I have come to the understanding that noone in the industry knows what to make of this whole emissions debacle. some people say cummins should recall all the suspect engines, cummins says it isn't responsible for the problems the systems are having , the various parts manufacturers are hiding behind the fact that not one of them is responsible for the entire system. we as consumers have not used the us legal system to hold these people accountable, why because we would rather be riding down the highway trouble-free. OK this is the problem epa mandated fuel efficiency be increased and emissions be lowered,great idea poor exacution we as drivers know 1 thing and o/o know it better than most, it takes fuel to do the job these vehicles have to do. so much so that even when fuel was a dollar a gallon it was still the biggest part of our overhead. so why knowing this did we ever assume we could get a 15 litre deisel engine to produce less emmisions than we let import manufacturers put out of four cylinder deisels 20 years ago[no I'm not going to look up the actual figures]. everyone should have gotten trapped behind an Isuzu pup on a two lane mountain road. So all in all what I'm getting at is don't let the dealer or manufacturer of your cars trucks equipment or products off the hook. BEFORE HAVING ISSUES WITH MY HEALTH I WAS PARTY TO THE PROBLEMATIC B/S THAT IS THE CUMMINS ISX WITH SCR DOC DEF DPF PROBLEMS WHAT I NOTICED WAS BEFORE THE EXHAUST SYSTEM STARTED ACTING UP AND SENDING CODES THE ENGINE STARTED TREATING ALL LIQUIDS THAT HELP IT SURVIVE LIKE CONSUMABLES IF U WANT TO FIX YOUR TRUCK OR HANG THE RITE PEOPLE RESPONSIBLE FOR THE PROBLEM WE NEED TO ESTABLISH WHO IS AT FAULT 1ST CUMMINS IS AT FAULT FOR NOT HAVING BETTER QC OF THEIR PARTS VENDORS. BAD VALVE SEALS THAT ULTIMATELY LET OIL INTO THE EXHAUST STREAM PACCAR ITSELF FOR THE SAME WITH THE DEF UNITS TANKS PUMPS AND FILTRATION UNITS WHO EVER THE ENGINEER WAS THAT THOUGHT IT WOULD BE A GOOD IDEA TO RESTRICT THE EXHAUST TO INCREASE FLOW SPEED TO THE DOC AND SCR BY DROPPPING PIPE DIAMETER TO 4 INCH FROM 5 INCHS BLAH BLAH BLAH THE TRUTH BE TOLD MY EXPERIENCE WITH THIS TRUCK WENT VERY WELL BECAUSE I SAW THE PROBLEMS OTHERS WERE HAVING WITH THE VEHICLE I STAYED AWAY FROM RUSH FREIGHT LIMITED MY SPEED TO 55MPH AND WAS REWARDED WITH UP TO 11 MPG YES 11MPG IVE NEVER SEEN THIS FROM ANY ENGINE SO AT FIRST I WAS PRETTY HAPPY THEN THE VISITS TO THE KENWORTH DEALER STARTED AND I BEGAN TO DIG TO TRY TO FIND OUT WHAT THIS TRUCK THAT I TRUSTED ENOUGH TO SIGN A FOUR YEAR LEASE HAD IN STORE FOR ME .SOME OF THE AFOREMENTIONED PROBLEMS WERE WHAT I FOUND EVEN THOUGH I ALREADY HAD A TRUCK THAT I COULD HAVE FIXED AND MADE A BEAUTIFUL CUSTOM PETERBILT OUT OF. I CHOSE TO GET THE NEW TRUCK AND SELL THE OLD TRUCK AND I LOVED IT. MY WORRIES WENT AWAY AND MY MONEY STARTED BUILDING UP. SKIP TO 425,000MILES SCR CODE TRUCK DERATED AT DEALER BECAUSE I TURNED IT OFF DEF NOZZLE CLOGGED FIXED UNDER WARRANTY THAT STARTEDTHE PROBLEMS FOR ME OIL CONSUMPTION COOLANT CONSUMPTION FUEL MILEAGE DROP REGEN EVERY DAY. BAD EGR COOLER, BAD DEISEL DOSER, EGR VALVE, BAD BOOST SENSOR, BAD SCR ,DPF, DOC ALL BAD TRUCK USED LESS THAN 2GALLONS OF OIL IN 15,000MLS ...... NOW FOR THE TRUTH CUMMINS KNOWS THEY HAVE A PROBLEM AND IT STARTS AT THE PISTON AND LINER THE PISTON'S TOP RING IS POSITIONED SO THAT IT CAN DEVELOP LOADING OF CARBON DEPOSITS ON TOP OF THE TOP RING AND AROUND THE PISTON ITSELF BETWEEN THE TOP OF THE PISTON AND THE RING WITH NO WAY OF CLEARING ITSELF THIS BUILD UP OF CARBON CONTINUES UNTIL IT POLISHES THE TOP OF THE LINER AND FREEZES THE TOP COMPRESSION RING. UP AND DOWN MOTION THEN TURNS PISTON AND RINGS INTO CARBONIZED OIL RING KILLER. ENGINE DUMPS OIL FROM CRANKCASE INTO EXHAUST SYSTEM. BAD EGR COOLER DESIGN DOES SOMETHING SIMILAR TO ANTIFREEZE ONCE THE COOLER STARTS TO LEAK IT CONTAMINATES THE DOC WHICH IS AT THE FRONT OF THE LINE-UP IN THE EXHAUST EMISSION SYSTEM THEM DPF FILTER AND FINALLY THE SCR GETS COATED WITH EITHER AND IT FAILS TO WORK ALSO THE DOC FAILS BECAUSE OF CONTAMINATION AND THIS WON'T LET THE EXHAUST HEAT UP AS IT SHOULD. DEISEL DOSER SENDS FUEL SPRAYED AS MIST FROM DIRECTLY BEHIND THE TURBO INTO THE DOWNPIPE TOWARDS AND INTO THE DEISEL OXIDIZING CATALYST AND THE REMAINING EXHAUST GOES TO THE SCR WHICH IS AT THE END OF THE EXHAUST STREAM SO IF U UNDERSTAND WHAT I JUST GOT THRU TELLING U ALL U REALIZE THAT ANYTHING YOU ARE MISSING FROM THE FRONT OF THE EXHAUST STREAM IF IT'S NOT LEAKING ON THE GROUND IT'S GOING INTO THE EXHAUST SYSTEM EMISSIONS SYSTEM OF THE TRUCK. HOW IS THE SYSTEM WHICH IS DESIGNED TO BURN OFF DEISEL SMOKE PARTICULATES SUPPOSED TO BURN OIL AND SOOT AND ANTIFREEZE THE BIG ANSWER IS IT IS NOT IT WILL NOT AND IF YOU THINK CUMMINS PACCAR DETROIT AND MACK DON'T KNOW THESE THINGS ,OH BOY ... SO WHAT DO YOU DO IF YOUR TRUCK IS HAVING THESE PROBLEMS ???? I KNOW THREE NOT INCLUDING ME WHO HAVE HAD ALL THESE THINGS HAPPEN AND ALOT OF OTHERS WHO HAD WORSE AND SOME WHO WENT OUT OF BUSINESS AND WORKED THEIR @%^!* OF ONLY TO HAVE THE MONEY THEY MADE PUT A BANDAID ON THIS FREAKIN shotgun WOUND AND IF YOUR TRUCK IS APPROACHING THE END OF THE WARRANTY YOU HAVE VERY LITTLE RECOURSE BUT ---- TAKE NOTE OF THE ANTIFREEZE AND THE MOTOR OIL AND REGENS THE VEHICLE MAKES WITH A MILEAGE LOG CUMMINS THINKS THAT BY IGNORING AND SIDESTEPPING THE PROBLEM THEY'LL HAVE TIME TO QUIETLY ENGINEER THIS OUT OF THE PRODUCT WELL WHAT ABOUT THE GUYS WHO SERVED AS SUICIDAL LAB RATS FOR THIS EXPENSIVE EXPERIMENT AFTER THE BIG LAW SUIT SOME WILL GET A PAYBACK A PACIFIER TO KEEP THEM QUIET BUT WHAT IS REALLY HAPPENING IS EVERYBODY WHO EVER DROVE WORKED ON OROWNED A CATERPILLAR POWERED TRUCK IS SAYING %#*@ CAT WOULD NOT HAVE DONE THIS TO US THEY WOULD HAVE FIXED THIS ONCE ADVISED OF THE PROBLEMS I MISS MY CAT BUT THE EPA SAYS I CAN'T USE IT FOR 48 STATE WORK HEY CAT YOU HAD TO PACKAGE YOUR OF ROAD EQUIPMENT FOR THE US MARKET WITH TIER 4 EMISSIONS EQUIPMENT HOW ABOUT BRINING THAT CAT POWER BACK TO THE TRUCKING INDUSTRY

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I have a 2012 T700. I've had regen issues with doing a forced regen , sometimes it won't shut off, pulling hills a lot of bluish exhaust comes out and having a grass burner exhaust makes it look like my truck is on fire! The fault code shows dpf air actuator, which cleans the left over def out of the system when the regen is finished. Had a new Doser valve installed in January. Now my DPF full light is on and I regen, it doesn't go off.

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Feel free to shoot me an email or call if your interested in a solution kit. olsondieselperformance@gmail.com -Grant

701-680-2677

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Good infos can be found on http://truckecmtunes.com/

Cummins page on that web site: http://truckecmtunes.com/cummins-dpf-egr...

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After much research we found a guy to delete the DPF, SCR and DEF. It has basically saved our fleet and eliminated all the issues we were having. His shop number is 9403537278 and they are very knowledgeable .

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I will beat any competitor's pricing on Delete tuning + re-maps. olsondieselperformance@gmail.com -Grant

701-680-2677 -Thanks

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Brian Smith will be eternally grateful.
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