The rear A/C unit on my 2003 has FAILED now for the 5th time. That "thumping / clicking" noise. The 30 cent actuator unit (which the dealership happily charges $400 to fix) has broken for the FIFTH time. It's a cheesy plastic part where the small gear teeth break and, well, you're done. This is CLEARLY something Ford should stand behind but doesn't. Love the Expedition, but this is about as frustrating as it gets and always seems to screw up at the worst possible times .... like family trips. The part actually costs about $35 but the dealership will make it sound like technical rocket science and charge between $400 and $600 depending on what they think they can get away with. This has been my personal experience at Palmetto Ford in Charleston, SC on 2 separate occassions....as in, before I figured it out. Buy the part at the local NAPA store then talk a reputable service shop (NOT the dealership) into replacing it. Takes about 45 minutes....tops.