[alan &marge pepper]

its sounds like some errors made and i would like to think that it was not the guy you bought it from. if he can prove by receipt that it was overhualed than the noise should have been there before you bought it and there should have been some warranty on his behaft.
the torq convertor will drain back into the transmission and your dipstick will read high. once you start the motor it will reload it selve and your dipstick will read nomal which is full if it is not on the full mark then add till it is.
to double check this. is to get someone to hold the brake on and put it in drive and agaian check the fluid level the level should bee very close the same if not... your clutches are worn out or your torg convertor is no good.
I hope this helps if not its toast.