Looked Up my Regen Stats

[Cattletrkr]

I haven't gone into regen in over 330 hours of operation. That's somewhere's over 13K miles for me. Does that have something to do with the "sims" in my EGT sensors???

 

[MullenaxM]

You might be off a few degrees other than 100 F. First I will say that with my laptop reading the factory egt's the factory sensors see higher then the 1285 F that you are referring to when I pull a heavy load up a long grade.



Cracking is more pronounced in severe temperature changes that is why most dpf's are internally wrapped to retain some heat and temper cooldown. Next you could say well you will melt it but we are hundreds of degrees away from that point, double your regen temperature then you will melt it. In order to see this you are going to have more problems than a DPF.



The OEM engineers had to design the system to operate at long hard pulls, regen and shut down in Alaska sub-zero temperatures and to be able to do the same long hard pulls in the southwest where temps can get well above a hundred degrees. They also had to consider dpf exposure temperature required for regeneration, max egt temps that could be experienced in max towing, max egts with regen, environmental conditions and they also had to design the dpf to withstand this daily. Plus they also had to consider a cushion factor to be designed in.



I do have more information from work but it comes in "a corporate protected" documents that I cannot not release. The above info was all prior released information by the OEM's but this should suffice to answer the temperature concerns as they have come up before.

Very interesting, First off, 1285 F. is within the acceptable range. It is normal to see temperatures in the 1200 F. range during the De-SOx mode of the regeneration process. All I said is the difference between enough heat and too much heat is about 100 F. Cracking of the DPF's I see has nothing to do with severe temperature changes. The DPF's are internally wrapped to protect the ceramic material from the road vibrations of the exhaust system, but I will agree with you that it probably provides some heat retention.



I have never seen a DPF melt down, Never said it.



Second, You give the OEM engineers too much credit, If they had did all that testing, we would not be seeing all these issues with the 6. 7 liter exhaust aftertreatment system. I have seen those "Corporate Protected" documents also ( I'm assuming you are talking about Cummins as the "Corporate"). You must keep in mind that "Laboratory" testing and "Real World" testing are two different things. I see cracked DPF's weekly. Also I guess I must tell you that I am one of the ones that the engineers call when they need information on issues that "pop-up" in the "Real World". None of the engineers I talk to have ever been to Alaska, I have trouble even getting them to come to Texas.



Please understand, I am in no way knocking or putting down exhaust wraps, all I am saying right now is that" time will tell" if it is a good idea or not. In my position (Diesel Technician/mechanic) I see DPF issue Daily. Also I get information and advise from "Corporate" all the time. My job is to take the information I get,along with my experience, and determine the best repair strategy to get my customers back on the road. Sometimes I agree with the "Corporate" repair strategies and sometimes I don't, but I always do what I think is Right for the customer.



I guess The bottom line would be is that sometimes what you "read" and what you "get" might be two different things.



Thanks for the reply.



Mike

 

[MullenaxM]

I haven't gone into regen in over 330 hours of operation. That's somewhere's over 13K miles for me. Does that have something to do with the "sims" in my EGT sensors???

In what way did you determine that you have not gone into regeneration?



Mike

 

[HBarlow]

Good information, as always.

I find information sharing about issues and debates about strategies for using the new engines and aftertreatment systems very helpful.

Mike, I'm thinking about hooking up my fiver and driving over to Athens to pay you a visit next week for you to do the computer reflash and front end recall inspection. How does your schedule look for next week? I can stay a couple of days until you have time to work my truck in if necessary. A trip to East Texas will allow a visit to the new Willie Truck Stop and the Willie's Place XM/Sirius music studio at Carl's Corner on the way. If next week is not a good time I'll visit when you're not so busy.

PCarlson, I apologize for hijacking your thread with the above. I'll get back to the topic.

 

[PMould]

the way I was told,idle time is anytime the throttle is closed. just my 2cents.

 

[HBarlow]

the way I was told,idle time is anytime the throttle is closed. just my 2cents.

I assume you know there is no "throttle" on a diesel. I occasionally use the throttle term also because it is an easy way to say "foot off the accelerator pedal. "

Mike above said that the ECM interprets anytime the driver's foot is lifted as idle time. I think that also means when coasting down a long steep grade the ECM calls that idle time.

 

[WWhite]

On my 07 I have had 23 regeration on it at 22k, was on a trip back to AZ. My son was driving, scanned the truck on the OE side with my laptop, lot of great info. Was showing how may regen. that had been done. Like what Carson said shows idle time and at 10-20mph, 20-30mph and up. There over 200+ pid of info to look at.

Love my truck, wish the A/C was better.

07 Mega Cab 6. 7

William

 

[MullenaxM]

Although Idle time is Important , In my opinion there is another number, as a owner, I would be more interested in. Also as a Technician it is one of the data parameters than I look at to help with my diagnosis of trucks with issues with the aftertreatment systems.



I look at this number in my area and have formulated a base line and average for this number.



If I could get Ya'lls help (sorry, remember I'm in Texas) I would like to try something. I think this will help me as well as give you another tool to help with understanding the 6. 7 liter diesel and in my opinion give you data parameter that you can use.



First, Go out to your Truck and get in and turn the key to the Run position (don't start the engine), Next make sure your odometer is reading the mileage and is not on the trip meter. With the odometer reading mileage and the key in the run position, press and hold the trip meter button in, hold it in until the mileage numbers change ( It will take about 10 to 20 seconds for the numbers to change). When the numbers change you can release the button.



On a piece of paper record the number that displays on the odometer,this is the engine run time in hours, then push the trip meter button one more time, the mileage should be displayed. Record the mileage on the piece of paper.



Next, go back in the house and get a calculator. enter the mileage and then divide it by the other number.



When you get done come back here and post the answer. You'll probably end up with a number like : 36. 430834. Just post the whole number and the tenths,(ie: 36. 4).



Some of you may already know what this number means.



Mike

 

[HBarlow]

Mike,

I see what you're seeking. I didn't know our ECM recorded hours of operation or that the owner could read it. Average road speed should be useful in understanding why some trucks experience problems while others do not.

May I suggest that you copy and paste your above request into a new separate thread with a new title so that all ISB6. 7 owners will be more likely to see it and respond. Some may not open and view this older thread again, particularly if they've already read it.

I'll read and post mine tomorrow.

 

[MullenaxM]

Its not average speed, but good work.



You'll enjoy this. It's informative!!



If this works I'll start another thread.



Mike

 

[MullenaxM]

Heck, Lets start another thread.



Fireman, When I get another thread started I'll post your numbers there. I'll call it "Idel time and other Numbers"



Mike

 

[firemansdiesel]

Sounds good... .

 

[BHanna]

I seem to remember idle time is any time you're under 1000 RPM so going down hill counts as idle time to the computer.

 

[Scrappy]

as of my last fill up I had:



1180 hrs

32,958 mi.



27. 9