VW dealership parts are the $3 crank bolt and the $65 TDI sprocket
Your very much right though generally it comes apart on the highway damaging sevral valves and mushrooming the lifters badly to where become part of the head
Another question Quick TD when I removed the lifters I noticed that the four intake lifters had a longer stroke than the other three exhaust lifters is this just due to thier wear patterns (stroke related) or is this of no concearn