quote:A friend received this from Amsoil about Mobil's base stocks. Is this guy refering to the Trisynethic oil? I thought Mobil 1 was never group 3? SS is 4 + 5 esters.
Mobil typically uses a combo base stock comprised of groups 3,4 and5. Since we are striving for extended service intervals, we primarily with the group 4 PAO stock for stability over time. Thank you, Jim Van AMSOIL Technical Services