oils...(tongue in cheek)..DO NOT USE THIS !
As someone suggested, there are hundreds of posts about motor oils, viscosities, brands, and the benefits/pitfalls of each. However, I have not seen any reference anywhere to the use and benefits of "Castrol R". It used to smell just wonderful in a methanol mix being used.(I used to race sleds). I must reiterate; DO NOT USE THIS IN YOUR CAR. I'm wondering if anyone has heard of, or used this oil.
A mercedes is an inanimate object and therefore must respond to logic and reason.