RTG here...with a question ..what's your opinion of Quaker State 5-20 and 5-30!! have not noticed any comments either way..and would like your opinions
quote:I dunno, Beans (Actually, I DO NOT know beans), but Mr. Dyson, Gary, and a few others here do, and they have all mentioned in the recent past that the testing SM oils go through to achieve SM rating is pretty severe and passing of said testing is such that only oil of pretty stern base stock will pass, regardless of brand. After the SM rating is achieved, I would imagine the differences between SM -rated oils are pretty much limited to the additive package of any given oil of SM-rating.
Maybe... I wonder about the blind faith put into the SM rating.