I have a 2009 Honda Accord 2.4L 4cyl and was wondering when I should change the OEM oil. The manual saids wait until the oil life meter is down to 15%. The car has 6k miles on it and the oil life meter just is still at 60%. Should I change the oil at 7.5k or can I wait until the meter is down to 15% which will put me at around 10k since the meter isn't linear? About 85% of my driving is done on the highway cruising at 70mph. There is very little to no traffic in the remaining 15% of city driving. I do around 120 miles a day, 4 days a week. I'm fairly light on the throttle and rarely go over 3k RPM. I also take it easy on the throttle during the first mile or two from a cold start. The 09 is strictly a commute car since I use an older car for running errands. It doesn't get much colder than 30F in the winter and the summer can easily see temps of 100-105F. I will be getting oil changes at the Honda dealer like I always have. They use Castrol Syntec Blend 5w20 and Honda Filtech oil filters. Can I get at least 7.5k miles out of this oil with my driving? My 01 Accord 4cyl went 165k miles on the same oil and oil filter until I sold it because the transmission was on its way out. The engine in the 01 felt extremely good at 165k. I was doing 5k OCI back then because I did more city driving and was still use to the old 3k OCI myth. I plan on getting a UOA once I start using the Castrol Blend but would like some feedback from you guys. Should I stick with the dealer or find another place that uses a different type of oil? Would I need to go with a full synthetic to get 10k OCIs?