Originally Posted By: sm00thpapa
Castrol 4T is a dino oil and the Mobil is synthetic.
The Power RS Racing 4T 10w50 is a full synthetic. The 10w50 is SL, Jaso MA2, VI = 166, HTHS 3.7
The 10w40 is SL, Jaso MA2, VI=155 HTHS 2.9
Mobil1 Racing 4T 10w40 is Sl, Jaso MA, VI= 161 HTHS = ??