theres a guy on speed tawk foruns that has been testing all the oil,,,i was shocked to c some of the top oils u guys r tawken bout here tested notgood compared to the otheres
also oreillys auto parts house bran 20,50,tested as 1 of the Best yep house bran i was shocked ...it tested much better than castrol gtx which i been payen top dollar 4....nomore i switched oreillys house bran,,he also claims zinc is absolutely not need to run a solid lifter flat tappet ,,,he explains that most of the oil is designed to Not put Additives in it,,wen u do u delute it,do not put additives in ur oil he says,,an he is not gettin paid to write his stuff,he tests oil.
