Check those brake lines, mine 2003 XLT got rusted through a few years ago, not the pleasant experience to find it while driving. I since installed stainless brake lines myself to make sure it never happens again. I am sure doing it at the shop would cost $$$$. My car has 50K miles and in very good shape.
I had oil leak form transfer case, took a while to realize the leak is result of ?gross overfilling the transfer case with oil at the factory? - it was filled upto breather tube. It was so much of oil, so when operating it will expand and push the oil through breather tube out and on the case due to rubber extension was cracked. It may explain why so many folks complaining about Ford transfer cases leaking. All I needed to do is just drain the fluid and refill to the proper level and cut cracked rubber extension hose and reattach it to the breather tube.
Changing oil and coolant, replaced tires at 45K because of original continental started to crack (dry rot), replaced brakes pads around the same time. On the second battery (using maintenance charger), first one lasted 9 years without maintenance charger. It developed a small refrigerant leak from the condenser after just a few years of ownership, but it was fixed with leak stopper. I normally add 1 can of the refrigerant a year to keep AC running. Changed plenum actuator at the rear AC few times, very fragile, but like other folks mentioned - keep the temp controls away from the max or min to prevent gear damage in actuator due to constant torque applied at those positions. Some dude sells upgraded gears on ebay, so you can just rebuild original actuator and solve this issue for good. Replaced idle pulleys and belt due to the rust on pulleys - because of rare use of the vehicle.
Replaced all bulbs to LED and found some old bulbs melted/deformed plastic around it and in some cases damaged mounts (paddle light on the mirrors), so it was a good call to swap with LED.