Mobil1 synth 0-30 or 5-30. I change it every 3-5k miles with filter. I did just run half a can of seafoam in the oil for 500 miles or so. Man wasnt the oil black black black when I changed it.
not an easy thing, you'll have to remove the frt chian cvr Ford did put a cheaper plastic/nylon tensioners on the 4.6 in @2001 and there have been some issues, alot of people when they do a rebuild will get the older steel tensioners. did it make the noise before seafoaming?