Over a period of time, the upper part of the door/window surround can bend slightly causing wind noise. Tape the door up with easy peel masking tape climb in through the passengers door and take it for a spin, or try pulling/pushing the upper door frame in with a finger while driving sometimes there is just enough give to cause a noise. The trick is (if it needs it) is some blankets and a 4x2 piece of wood pass through the open window to east the upper frame back slightly, easy on a ford tricky on a jag done correctly doors will be super silent