So I have this little rattle inside the drivers door in my 06 GT. I'm 100% sure that it's in there. If you tap the door with your fist, or close it (obviously), it makes this short rattle like a loose bracket or something. Any idea what this could be before I investigate?

 

A friends 06 Vert had a rattle in both doors when closing them. I pulled the door panels and found mounting bolts for the window tracks loose in one door and completely out and at the bottom of the other door. About 15 min. per side to do.

 

Figured it had something to do with the window, thanks. Maybe a little loctite to preven this from happening again?