i change every 5000 miles with mobil 1 5w-30 for my 4.7. i run wix filters. i think standard mobil one says 6000 miles between changes, or maybe 7500, im not sure. however, most filters arent designed to be stretched that far i feel 5k is the limit for filters thats why i change mine at or before 5k. if i was running conventional oil, i would be doing 3k miles intervals.

 

3000, regaurdless, and i do mostly highway (20,000 in one year)... my mechanic does it... i just drive the truck! (besides i dont have a driveway, let alone a garage!) i believe he uses wolf's head, although i could be wrong

 

every 3000