Originally Posted by bct
I drove the doner car into my garage, pulled the trans and put it into my 55. It worked fine before I pulled it. The only thing I did different was add a floor shifter. Now that I think about it I didn't have the original speedometer cable. I wonder if that could have something to do with it? Plus, I'm still not sure if the sound would go away when I put it in neutral if it was the flex plate.
Cracked flex plate under NO load will often be quiet , unless it is really broken in pieces.
No load would be in park or neutral.