Mercedes S Klasse Diesel Belt Squeal Tensioner Issue

Sounds familiar. I had similar engine noise on my old BMW 5 series. Belt handover completely stopped working. Did you check the tensioner pulley That's often the culprit. What's the timing belt condition

Yeah, tensioner pulley seems shot. Belt-handover no longer works. I suspect the belt handover itself is defective. Any experience with replacing just that part Or is it tensioner assembly time

Right, if the handover's gone, it's tensioner assembly time. On the BMW, I tried messing with just the pulley, but it was a waste of time looking back. Considering the distance you've driven, I wouldn't risk it. Get it sorted at a workshop and be done with it.

Roger that. Appreciate the confirmation. I bit the bullet and got the tensioner assembly replaced. Cost me 455€. Engine noise is gone, belt squeal is history. Thanks again for the advice.