1989 300SE Harmonic Balancer?
 

Guys....where can I get a new balancer? Mine apparently slipped (destroyed the X11 Diagnostic) and is mis-firing. The car runs, but terribly. We have removed the front end and have the actual crank/harmonic balanced pulled off - but I have no idea where to get the part? Do they actually fail? Suggestions?

I got mine off of ebay..... pretty cheap....and easy to change..

with mine the rubber facing was separating from the metal plate...

That's exactly the issue with mine! Made quite a racket!

Balancer replaced - car is running perfectly. Only mishap was trying to get the transmission cooler lines back threaded - they are very difficult (mine were original)....Good Luck

And yes, yours is not the first to fail.