My 1997 S500 recently had the Harmonic balancer (vibration damper) break. The rubber holding the metal parts together became so perished that the metal parts separated. When it happened it sounded terrible, almost as though the car had throw a connecting rod. Fortunately I was less than a mile from my mechanics shop and was able to get the car there without damaging anything. He installed a new one but when he got down to installing the last bits (there were a lot of things that had to come off to get to the broken part) he had me come by to look at the cast aluminum cooling fan. It had a few small cracks near the base of a couple of the blades. He says that it's fairly common for the blades to break off at speed and damage the hood and other components.
I authorized replacement with a new one but now wonder if failure really is immanent. Has anyone experienced a failure?