My 97 F-150 XLT driver side door rattles when driving down the road. I have installed new shocks, rotated the tires, and realigned the front end. It seems that the noise is getting worse since I now have to drive back and forth to work on a new concrete road!

 

adjust the latch on the door post towards the inside,if it stills rattles then you may have a genuine ford assembly tool left in the door

 

there are things in the door that can break and rattle. if everything ok in door. try some white grease or somthing like it. to lube the latch assm. just put some in where the striker goes and open and close door several times. then wipe off what is not needed. i have seen them make alot of noise. in trucks that travel in dusty areas. might help. good luck. the ford dealer here lubes all of the latches when doing L.O.F.