Dad went to the dealer today and of course, he could not duplicate the problem. He asked to speak to a tech. They decided that based upon the symptoms it sounded like the flaps in the turbo that allow the air back into the engine might be malfunctioning. I've read through some of the two stickies above but see mostly tire wear issues and steppers
: Anyone else share this issue. The tech said he would check for service bulletins but he admits he has no real time experience on this vehicle. They have only sold one other V10 diesel and it only has 3000 miles on it.
Thanks in advance.

Thanks in advance.