The harmonic balancer failure is directly related to the failure of the crankshaft pulley bushing going bad, as I understand it, This is a common problem. My 98 e320 just had the crank pulley replaced UNDER FACTORY RECALL!!!It appears MB has finally recognized the problem. EVERYONE IN THE SOUND OF MY VOICE PLEASE CALL YOUR LOCAL MB DEALER AND ASK ABOUT THIS RECALL. I found out about it by accident, my local mechanic shop was going to replace my crank pulley because it was squealing on start up and when they went to get the part they were told about the recall. Because they are honest, they relayed the information to me and viola! I took it to the dealer and they replaced the pulley and the belt at no charge. I was told this is a very recent recall so CALL THE DEALER. I had my work done at Rader Mercedes Benz in Augusta, GA. Hope this helps somebody.