Recent content by hermit

That's NOT proof! "...can be voided" is a vague way of saying nothing. A contributor from Australia on another Corolla site states his owner's manual gives acceptable oils up to 20W50. Is this site independent or owned and managed by AmSoil?

Response from bobistheoilguy website: "I have the new manual in front of me and after promoting their 20 weight for a couple of paragraphs, the last line on the page reads: "An oil with a higher viscosity may be better suited if the vehicle is operated at high speeds, or under extreme load...

"Using a petroleum oil in an engine that requires a superior performing synthetic oil will cause engine damage." Where's the proof for that statement?