I have done a flywheel replacement and have drove my f150 about 600 miles and now its making a noise like something is lose[ like metal vibrateing on metal ] Ithought it was a crossmember bolt loose or something but it sounds like it is comeing from the trans. it dont do it all of the time DAZED AND CONFUSSED

 

what kind of noise? Does in make a ching-chang noise as you get on and off the throttle while driving?
I would check that all of the bolts are tight first.
Alan