I'm looking for help from someone who might know about a problem i'm having. My 2002 explorer is making a humming noise from the rear-end berween 55-70 mph. When I let off the gas it goes away, but as soon as I step on the gas it comes back. Been to the dealer twice. First time they stated Ford knows about the problem and they are working on it. Second time they stated Ford said to lower the fluid in the rear-end, but that didn't work. Any information would be great.