I had that same problem in my ‘96 Explorer and was finally able to trace it to the base plate of pre-famulated amulite surmounted by a malleable logarithmic casing. They were interacting in such a way that the two spurving bearings were in a direct line with the panametric fam. It wasn’t hard to fix once I understood the root cause.
Seriously, there are some great Ford sites out there. Come to FR for the humor and snark.