"I have used both 5w-20 and 5w30 in either of these brands and the difference was neglible on noise."
I've read many posts like this that claim "Brand X" oil was noiser in their engine than "Brand Y". I'm still not sure I understand how oil brands can vary in "noise level" (when used in a mechanically sound engine). Personally, I've never experienced a difference in engine noise by changing oil brands - whether I used conventional or synthetic. Wouldn't engine noise more likely indicate a mechanical problem?
I've read many posts like this that claim "Brand X" oil was noiser in their engine than "Brand Y". I'm still not sure I understand how oil brands can vary in "noise level" (when used in a mechanically sound engine). Personally, I've never experienced a difference in engine noise by changing oil brands - whether I used conventional or synthetic. Wouldn't engine noise more likely indicate a mechanical problem?