john, i had this same conversation with tom langdon a couple of years ago. if you don't know tom, he's a retired gm engineer and has never lead me wrong on any advice. he told me that if i use the recommended oils/filters and change then at 3,000 miles, (or more often during severe use) you'll get good service from your engine. the extra claimed protection/cost does not warrant synthetics. following his advice, i put 176,000 miles on a 4-cylinder s-10, and 121,000 miles on a toyota rav4. neither enine ever gave any internal engine problems. i have since built a 4-cylinder chevy II powered model a and will use the recommended oil in it. at 65, i hope to drive it for the rest of my life!
