sounds like a vacuum cleaner! I'm not getting any dash light indicators and my performance doesn't seem to suffer however, the noise is very annoying and can be pretty loud when cruising 70-80 mph.
This is very weird as it comes and goes and I can't make it appear by doing anything specific. It does show up random. Hot engine...cold engine...slow speeds....high speeds.
It can be there when traveling at 70 and at times when I stop or slow to almost a stop and then speed up again it may disappear for a while and then reappear later down the road.
Have not taken it in to my dealer yet. Waiting for my friend to plug his computer into the OB plug and see if anything shows up.
Anyone else experience anything similar?

 

Might be a good idea to look the turbo over carefully for excessive carbon preventing full function.

 

Dropped it at the dealer today. I'll let you know the outcome.

 

Thank You, curious as to what they find.

 

The dealer had it diagnosed and repaired in a few hours.
It was something to do with the clutch on the fan. It was not allowing it to disengage when it was suppose to.
They had what ever parts were needed in stock and got it done.
I took it for a high speed spin for about an hour after picking it up and it seems like that is what it was.

 

Had a few fan clutches go south on gas engines, but never on a diesel. First time for everything,lol. Thanks for the update