I have a 2002 Explorer with the 4L V6. Good luck at 80,000 miles, so i bought a 96 Exp with V6 adn 150,000 miles for the kids. Went to change engine filters and the older motor is PH8, new is PH2. I have read a little about OHC and OHV motors. I am mechanical knowledgable, but not on theis V6.-- would like to know the difference in these two motors, or if they are basically the same motor with some different parts? What is interchangable?