99 F150 4x4 has a squeal that starts about 10mph and stops at 40 mph going up and the exact pace going down.

The sound is similar to a belt squeal, but when you slow down below 10mph it goes away, which seems to discount a belt problem. Anyhow, It's not real loud

I have removed the brake pads and reinstalled them after a thorough cleaning and this morning I teflon-sprayed the upper and lower ball joints.

The best I can tell it has something to do with the rotation of the front left wheel, but I cant figure it out. In addition, when I make a sudden left twitch with the steering wheel, the sound disappears for a moment.

Any ideas would be greatly appreciated.
jt