This morning truck went into regen about a mile from home after a trip to get fuel and the office.
I park (engine at idle) and walk over to the DPF.
It’s popping as I would expect, stops, and then pops a few more times (sounds like clicking a lighter).
I noticed a small amount of white smoke from the exhaust pipe (before it turns up from the tips) so I decide to kick on the high idle @ 1,400 RPM to see what it does.
Sure enough, the truck is still in regen mode.
(I’ve also recently noticed regens continue after I stop at a light so this made sense to me.)
The small amount of white smoke came and went for about five minutes.
The exhaust was extremely hot coming out of the tips (again as most of us know is the case during regen).
Even a lot of driving and then high idle doesn’t produce that kind of heat while parked.

So the real question is, did it complete a regen in my driveway? My guess is yes.
Or if we don’t want to call it a regen, then the exhaust system was doing something that wasn’t normal while idling or high idle.
When it was done, the exhaust heat was where I expected it (didn’t cook my hand at six inches away).
It took another 200 miles today before it went into regen again on the highway.

Your next question is did I stick a piece of cardboard box near the tips….um, yes. Haha.
I could smell that familiar cardboard burning smell (with slight discoloration) but it didn’t smoke or burst into flames in case you’re wondering but that’s how hot the exhaust is.

The last question is, is there supposed to be smoke coming from that part of the pipe?
I glanced up there but didn’t see any vents. I’m going to look more closely in the morning when everything is nice and cooled down.
It was 41 degrees F at the time of this video. It sure smelled like smoke (not steam).
I know...this was a long post.
See attached youtube video (first time for uploading a youtube video...).
YouTube - MOV05071_1.wmv

 

I can't speak of the regen activities, still learning them on this truck myself. I do think it is odd that you are seeing the white smoke at that particular spot though. Are you sure it was coming from inside the muffler rather than something burning off the pipe?

 

The more I look at the regen issue, the more I think it was a mistake to not offer a electric heater regen (that you plug in) as an alternative to diesel fuel powered regen.

 

I think you have an exhaust leak! I have never seem one smoke there that didn't have a leak.

Disclaimer..I have never crawled under one of the 11's.

 

I'm not 100% sure it isn't something burning (did't see anything) so I think Scott is correct.
At normal 600 RPM idle it was simply spitting smoke while the DPF was complaining since it didn't complete a regen properly.
When I high idled, the smoke was more abundant (the video was high idle) because there is more exhaust gas moving through the pipe. So, it has to be coming from inside the pipe.

It doesn't do this normally so it's either always had a leak (which I would have never noticed driving) or it is a recent issue and I was lucky enough to catch it while I interrupted a regen yesterday.

Great...back to the dealer. At least I have proof.

 

Someone would ultimately plug it up in their small garage and cause a fire despite warnings in the owners manual.

 

This method of regen is standard equipment on many buses and other DPF filters.