I had the same problem in my 2003 Expedition, the sunroof was leaking in the right rear ceiling. I had a mechanic take the sunroof off, blow out the drain lines, and check around. After following the water trail, we determined it looked like it was coming from the luggage rack. We screwed the luggage rack in tighter and I have not had a leak since then. I have my fingers crossed... Unfortunately, I have been concentrating on much larger problems. The computer system is going berserk. I have had a "door ajar" for over a year now. Finally, I replaced the "door ajar" latch 3 days ago. It was silent for a day. Yesterday it came back on twice as bad. I had my mechanic play with the door latch and it was silent again. About an hour later, the battery light came on and started going on and off repeatedly with a message "check charging system". Also, some window switches are working sometimes and other times they don't. I'm guessing this is the computer going bad? Any advice would be great, as the constant dinging noise while driving is getting aggravating.