2003 Explorer Rear differential Whine
 

I bought a 2003 Explorer with the V8 and 3.73 rear end. I has a bad whine that starts at about 50 MPH. It is under warranty up to 60,000 miles so I can get it fixed but reading the forums online it seems that Ford has not figured out exactly how to permanently fix the problem. Does anyone know the background on the problem, what is causing it? Should I wait a few months for Ford to get a better handle on how to solve the rear end problems permanently. It seems that the fixes work for about 10,000 miles and the whine comes back. Any ideas??