Originally Posted by Nelson G

I don't know if you have read through540 Rat's blog but the guy who writes it is a: I’m a working Professional Degreed Mechanical Engineer, and Mechanical Design Engineering is what I do for a living. A Mechanical Engineer is clearly the most qualified Engineer to test motor oil that was formulated by Chemical Engineers, for wear protection capability between mechanical components under load. He has lots of info on all the different kinds of oil and what he recommends. Here is the link it is a very long read and when he gets time he updates the info. His oil of choice is Quaker State and Quaker State® Euro Full Synthetic motor oil is Mercedes-Benz approved:229.3 229.5.
Here is the link: https://540ratblog.wordpress.com/