I've worked on the Ford Triton V8's. These cars are way easier to work on. I remember working overnight the first time to get to the spark plugs on the Ford. Still takes about an hour now, but still these cars are 10-20 minute spark plug changes. And, these cars have the blend door like the Ford, but I haven't heard of anyone's going out. On the Ford, it's a common problem of the plastic blend door breaking off or the circuit board in the blend door actuator dieing. RockAuto.com sells a Dorman blend door actuator for about half the dealer cost when that goes on your Ford. It used to be a dealer only item. I think Ford just didn't calculate the right amount of thermal expansion so the door drags. Can you tell I hate working on Fords, lol.