I have noticed lately that the front of my truck is squeaking. At first I thought it was the serpentine belt since it was due for a tune up. But after awhile I noticed it was getting louder when I'm moving and doesn't seem to be noticeable at stops. I don't do it on start up but if I drive for a little bit it starts to squeak again. Any idea what it could be? Has anybody else noticed this on a 2003 FX4? If so how did you fix it?

 

ball joints. mine was doing that i get out of the truck and hear a squeek.
replaced up and lower along with inner and outer tie rod ends. fixed that problem.