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Regen question

13K views 24 replies 16 participants last post by  RayK  
#1 ·
I have a 15 2500 CTD with 36000 miles on it. Today while driving I received a message on the dash that my truck was doing a regen and the filters were 100% full. This is the first time I ever got a message and after driving for about 5-10 minutes (normal speeds) the message counted down to 90,80, then 70 % full. My question is wouldn’t it come up before being 100% full with another number telling me they were almost full?


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#2 ·
Nope, you only get that message once its FULL. Usually short trips, stop and go driving does not allow the engine to heat up well enough to burn it off. If it can't get up to temp for a long enough time, it can't complete passive or active regens. I got this message ONCE on my 16 last summer and immediately bought an Edge CTS2 monitor. It tells me when the truck starts a regen when I'm driving. Sure enough, there have been times I would have shut the truck off, almost home, etc when it starts the regen process and I would have shut down in the middle of it all. So now, I just keep driving until it completes its cycle before shutting down. Mine does it every 900-1000 miles like clockwork so I know when to expect one. LOL I would get a monitor so you know,
 
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#3 ·
Since you have kept driving, on average how long would you say it takes to finish a regen? You can turn on the instant MPG, you will see a clear and noticeable drop in MPG, and I know I have pulled into the house and turned it off during one. Once its closer to out of emissions warranty I might care more, but curious how long I would have to drive.
 
#4 ·
100% might not mean it is actually 100% full with no room for more. Caterpillar and other brands go from 0% to 140%, 140% meaning it is junk, or maybe it is. I have had machines at 146%, made what ever repair was needed, and then made a regeneration back to 0%. Also Caterpillar machines don't start throwing bells and whistles until 100% .
 
#8 ·
I saw it once on my '13. It was strange and I took a pic of it. Never saw it again. I drive mostly highway and tow fairly often.

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#9 ·
Your truck performs active regeneration often, but the only time you get that message is when the DPF gets near its soot capacity.

Idling or lots of short low speed trips will fill it up faster, long highway trips help keep it cleared out.
 
#10 ·
Your truck performs active regeneration often, but the only time you get that message is when the DPF gets near its soot capacity.



Idling or lots of short low speed trips will fill it up faster, long highway trips help keep it cleared out.


The only thing is, my driving habits haven’t changed and it was the first time it ever came up saying the filter was full.


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#15 ·
There’s no need to have a monitor to know when a normal regen starts. All that does, is puts in your mind that you need to drive around aimlessly, wasting fuel until it’s finished. If a normal regen starts when you’re done using your truck, it will pick back up where it left off next time you use it. Believe it or not, they designed the system so that people who have absolutely no idea what a dpf or a regen is can operate these trucks. That’s why the manual says it’ll do it’s thing “with no further input from the driver”. And, when you do so many short consecutive grocery getting trips that it doesn’t have a chance to heat up and complete its process, the EVIC will let you know, and that when the manual says to continue driving it.
 
#18 ·
Well the other thing is that regen works best while hot, the hotter the better. I would rather drive around aimlessly for 10 extra minutes and let the regen happen while hot and while it is more effective than have it restart when not up to temp and have it regen longer or less effectively.

It’s all theoretical, until you have issues with your truck being in perpetual regen and the DPF being plugged and your mileage down 20% and you are trying to figure out why.

I think the emissions systems do a good job and relative problem free, but I think you need to use the truck as intended. If it’s a run around town, not towing, no highway truck I think you will have a few issues, like I did. If you haul RVs or quadruple stacked trailers, you should be ok.