Hi. I'm new here but have been fussy about changing oil in my cars/trucks for many years. Right now I have a 2003 Nissan Sentra XE with 61,300 miles and Castrol Syntech 10-30 in it. I switched to Synthetic last Winter while trying to improve my gas mileage, at first to QS "Q" brand, then was told to NOT use QS oil, so I drained it and put Syntech in. I only have about 2200 miles on the Syntech now (with a K&N oil filter that are often on sale together). I was wondering about the intervals to change it at now. Guy at parts store where I got the oil said 9 months is OK but after reading here and other places I think 1 year ought to be OK. Is this correct in your opinions? The type driving I do : I only put about 3000 miles a year or so on it. I have a motorcycle I ride much of the time. I drive it around town a lot, or to a town that's 8 miles away or to another place that's 13 miles away, or sometimes just to the store that's a mile or two. I live in East Tennessee USA. Was surprised to learn that the "can't go back to dino oil after synthetic" saying is a myth to many people. Do you all agree here? I don't think it would be a great idea for me to go back to dino oil but I'm not sure. I just want my car to last a long time with the best oil. I do OCs myself and am not real crazy about it so the once a year OC vs the 6 month OC with Dino oil is probably the wayI'd rather do it. Before Synthetic I ran Castrol GTX 10-30 in my car. So, in a nutshell, my main question is : is one year OC OK for Synthetic, and is Syntech a good enough oil to use or would it be better if I used some other similarly priced brand?