Its no doupt the syns. last at least twice as long as regular oils. I have no fear at all of going 7000 miles between oil changes with the syn.

I did not always feel this way about synthetic oil, I was a big doupter of it till this past summer. I sucked it up and did a little experiment with it.

Took a ride on my motorcycle. They are aircooled v-twin harleys. I put syn oil in the one and ran it coast to coast this past summer. Atlantic ocean to the pacific. Noramlly I would have had to do two or three oil changes. This time I did no oil changes, the thing ran quieter, cooler, and gas milage was up. I did this just to see if the syn was all it was cracked up to be. When I drained the oil after almost 7000 miles it was still realativley clean. My riding partner could not say the same, Same bike, same milage, regular oil. His bike ran hot ( had to stop in death valley for over heat), the valves clattered, and he had to change oil twice along the way, both times the oil was black. I know this is off the subject of cars but a good example of how great the synthetic oils really are. One thing about any oil change , make sure you use a good filter, wix is a good one , Stay away from Fram and the cheap filters, a bad filter is as bad if not worse than a prolonged oil change.