I have a 00 Expedition and the rear air shocks are not pumping up. I have replaced the control module the first time that happened and the system worked fine for about a month before it happened again. I had a mechanic look at it and he managed to readjust the height sensor and it worked for a week -- now he tells me that the rear height sensor needs to be replaced. Part Number is F752-5359AA-- but I don't want to spend 250 on that 1 part. Any one know where I can find a used part a bit cheaper than that? T Bros Auto parts (an ebay store) has many height sensors but not the exact one for the navicator/expedition. Any susggestions would be appreciated.