Just looked at another white 2002 F150 to replace my black F150 and every one I look at has these small rust colored specks on the lower front of the box. They do not seem to come off either. The body shop guy said it is hot brake rotor and pad flecks that burn the pant and rust. He said white is a problem

 

Because they show up more on white. I'm on my second white truck, and you'll see it all over on them if you look close enough.
It doesn't show up on a dark colored truck.

You can get it to clean up though. Any number of cleaners/polish/wax will work.

-jeff b.

 

The rust specs are rail dust,it comes from the transport trains that deliver the cars&trucks from Ford. It is easy to remove with a clay bar and some elbo grease.

 

I've never had that problem with any of my white 4x4's. And I'm on my 5th. My 2003 SCab didn't have any evidence of rail dust, I clayed it anyways.

 

Nuff said!