true, but all cars/trucks do it, not just Fords
Mine is pretty clean since I have aluminum and such (no live axle like the 05+ have). Its worse for cars up north though. They do undercoat the cars, most of the rust is on the driveshaft and live axle. Both can be removed and cleaned/coated and you would remove 90% of the rust if not more as the floor boards etc are coated to protect them.