I have never used synthetic oil. I know it is supposed to last longer. Other than than, do you feel other difference, fuel economy, for instance?
Do you still change oil every 3k miles with synthetic?
Yes, there is difference in how the engine sounds, especially when it starts in cold winter mornings. I didn't notice a difference in fuel economy maybe because I switch to synthetic right away and don't pay attention. I believe synthetic is just a better oil for my cars. I tow a TT with my Outlook and even after a long haul I don't see any rapid hit on % of oil life left; looks like it deteriorates in the same pace as going solo.
I had a Suzuki Esteem sedan for 9 years and always drove on Castrol Syntech. When I sold it, the car had 160K miles and now has 35K more. The engine is still going strong (1.6 l, 4 cylinder) and it passed emission test with flying colors.
I change oil in the Outlook based on what the DIC tells me but don't let it go under 20%. With my Civic, I go 2K miles extra than the book says.