Its all about what grade of oil it is from cude ie. Is it triple refined oil.? Etc.... Then what addictives are added during blending. . I buy from LSA oil local guys hear ! They said to me most fully synthetic oil they have is hi-syn 5w 30 they also said nothing is 100% synthetic coz its all cude its all about how many times it refined n fracked. Then the addictive. So i buy Hi-SYN 5w30 then i add liqui moly MOS2 im still researching if i can blend a 0.4um ceramic compound there is a name but cant remember it we have it at work 1kg of this grease blend is $2k We use it for dooms day to get the machine some time till the parts arive!!!!!!. [emoji4]