Please Help, Im pretty sure my crankshaft balancer came off when i started my car up today. do you think that the pully under it is going bad, or the balancer just got wore out? what's the easiest way to replace it. do i need the three-leg puller like my Chilton says or the tool J29113 (Crankshaft Balancer Installer)?

I have yet to have the privilage of replacing one of these. Please help, any feedback would be a great help!