Originally Posted By: davidyan
Does anyone know if Mobil 1 Extended Performance contains Ester additives? Also, is it a group 3 or 4 oil? I've heard the non-extended performance version is a group 3
The regular M1 has some grp 3 but also 4-5. How to call it is for someone else to say. A few months ago I called Mobil tech and they said all M1 oils were Grp 4.