I change my oil every 5k miles using Mobil Synthetic 5w-30. Don't trust the "oil life indicator" on your info cluster. I check the oil level frequently and monitor oil consumption based on how much oil drains out. I am seeing appx 1/2 qt of consumption now, which is completely acceptable IMO. I haven't done an engine oil analysis yet, probably should. I only run e50 in the summer (waiting for my launch control from Adam to flash e50 now!!). I run pure 93 during the winter months and e30 mix in the spring/fall time.
