Update: Ford dealership was not helpful much. No codes on scanner, but did find out the previous owner had PTU changed as it was from a wrecker, had the yellow paint marker on it. Also I noticed (they did not) that the ptu was leaking. Not much but some. Technician filled it back up. Going to take for a long drive this weekend to test thoroughly. If no issues, then oil leak was the issue but will still need a seal or new PTU. Also, PTU APPEARS to not have any wiring to it. If the ptu is overheating due to lack of oil, how does the car know it is hot? Where is the temp gauge located for the awd system? Is it possible the rear transfer case is low on oil? And is the rear transfer case oil refillable?