You mean timing chain?
MB timing chain can last and go beyond<br>
100kmi.if you change your oil religiously.<br>
At 50kmi.which is aproaching,I will have it<br>
inspected for stretch and look at the rails.<br>
Make sure you have a tech that really know<br>
and work on Benz'engine.The first indication<br>
of failing TC is a loud solid ticking noise<br>
at startup on a cold morning,that last at about<br>
2-5 secs.Hope this help.