As far as I know Mobil 1 is actually the crappiest oil there is. I read lots of post that Mobil 1 downgraded their synthetic oil from Class IV to Class III which is not really a fully synthetic any more. I read that Castrol and Royal Purple are still Class IV oils, AMSOIL being the best since its Class IV or even V
I used M1 alot, but probably will switch to Castrol...not that it really matters, but read lots of BS on Mobil1
EDIT: Mobil1 5w30 is Class III, 0w40 is Class IV ...... thats what pips say < not 100%,but confirmed this and its true
EDIT: Only German made Castrol is Class IV, others are also Class III. Redline oil is Class V
Last edited by Kolyan2k; 06-03-2011 at 06:54 PM.