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ShopForum, Tech Help, the second thread is "Crankshaft Balancer Failure", has all the information you'll need and then some on your problem. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~Today the central belt pulley (I'm not sure of the correct name - it is the
> large pulley at the bottom center of front of the engine) on my '99 E320
> came apart. The car only has 62K miles, but when talking to the dealership
> on the phone, this seems to be a fairly common problem as they knew exactly
> what I should be looking for before I opened the hood. Has anyone else
> suffered from this same ailment, and if so do you know if the dealership
> replaces it with a pulley made out of more durable material (the current
> pulley looks like it is made out of metal and rubber)?
>
> Thanks
>
>