atraudes

Well shoot, that's awesome! You were not getting the same clacking sound as me, correct? I guess I should replace the valve and magnet on that cam for good measure. It already has a new valve, but the one I got felt a tad notchy too. I figured it was normal at the time.

E55Greasemonkey

Yes, I'm still getting the clacking sound from the passenger fender. Same as my wife's ML with 80k and same with my (sold) 211 wagon with 82k. All 272's do it. I wouldn't do anything until you have a fault code. I've learned the ECU very carefully monitors the cam position and will let you know if something is only slightly off with the cam adjustment.

VicVegas84

This is one of the most useful and thorough thewds I've seen in years. Just read to the letter and wanted to say thanks to all who contributed. I'll probably be firing off some PM's in response. My 161k mile 2011 GLK 350 has this same distinct noise.