hi guys this is my first time here. I here this site is where its at to find useful info, here's my dilema I have a 00 civic 1.6 SOHC 135,000 Km and want to know syn is a good idea. I just switched over to the new 5 w 30 Quaker State Q and 700k into the oil change my level has dropped. Should I go back to Castrol GTX, or go to a blend or stay with Q syn. Thanks. I live in canada where it is cold in the winter.