My 2002 Ford Expedition has 55,000 miles on it. Took it in for sceduled oil change, dealership came back and said the rear differential has a leak. The service guy explained how we had to pay for all the fluids too because once the differential was opened up for the repair, the fluids are lost. I pointed out that we had an extended warranty on the Expedition, and he suggested that it might pay for part of the labor. As I read my warranty, it pays for anything not considered maintenance or normal wear and tear. It lists a number of things that are not covered, but rear differential repairs are not mentioned under this. I have owned many vehicles, several with 150,000 miles or more. I have never had a rear differential leak before, so it seems to me that it is not a maintenance or normal wear and tear situation. At 55,000, I feel this is an odd thing to occur, particuliarly since I have followed the maintenance book and done additional maintenance as it was suggested; I don't drive in any unusual or challenging conditions, and this is a 2wd vehicle. Has anyone had this problem with their Expedition with similiar mileage? Does anyone know if this should be a warranty situation? I suspect I'm being sold something that is either not needed, or that I shouldn't be paying for. Please help!