i've been searching lots of old threads trying to learn the top dino oils you can buy off the shelf. so far ive found out Chevron Supreme is really good and Castrol GTX is also a good brand, correct me if im wrong. I have always been a Valvoline user but maybe its time to switch. I was suprised to hear people recommending Penzoil. all of the car boards i'm part of i had always heard people say poor things about the brand and im still weary of it. but back to the point, what other brands do you guys recommend excluding chevron supereme and castrol gtx