My wifes mountaineer is overheating. It has the 4.6 v8. I read the temp today with my scangauge and it went up to 230 then I shut it off. I notice once it gets hot the fan will constantly blow and makes a loud whooshing sound. I also notice that when it changes gears theres a quick screech under the hood. I drained the coolant today and Im gonna fluch it and put a new themostat in. I noticed that there were air bubbles in the overflow tank coming from the bottom and with the motor off theres a constant slight burbling sound in the motor. SO could this be headgaskets, themostat, waterpump, hole in the radiator?