As G-Benz pointed out, look at the sticky at the top of this forum.

MB identified the problem ages ago and they are dilligently working to replace balancers that have been identified. This is at no cost to the owner.

My brother in law is my tech at the dealership. A few years ago I was visiting him in his stall and saw a big note that he had taped to his toolbox lid. It said "Don't forget to check Harmonic Balancer."

MB has been watching for these and replacing them. It's not as if they are refusing to acknowledge or correct the problem. If you are worried, all you have to do is go to your local dealer. You don't have to pitch a fit with a government agency like you were protesting Agent Orange or something.

Have a great day,