Harmonic Balancer on 1996 Dodge Ram 1500

My Harmonic Balancer (Haynes Manual calls it Vibration Damper) broke loose. Does anybody know the socket size for the retaining bolt?

1 answer
I think it's a 1 1/4". My book says it's torqued to 135 ft lb's. How did that bolt come loose? It didn't strip did it?

Here's a link where they're talking about it... hope this helps you. One person here says they can work their way out but I don't know
http://www.dodgetalk.com/forums/showthread.php?p=2583542