03-04 Expedition Rearend Whine
Just a FYI to all you fellow Expedition/Navigator owners with the independent rear suspension:
If you hear a high pitched whine inside the vehicle....take the car into service and have them replace the ring and pinion gears. I had this issue right from the showroom floor. At 12K they were replaced and problem solved. Ford does know about this issue....and there was no argument for the replacement.