What we do know about Amsoil based on VOA's is that they were late in the game to using Moly and have always used a boat load of calcium, which is great but at the same time keeps the SA very high. Not knocking their oils at all. They are very very good. But I don't see them as a leader per se when it comes to additive chemistry.
They have folled Mobil in several ways:
Went from claiming PAO to now not disclosing base oils
Mg to overbased Ca
Moved to moly
15 years late in making a world class 0w40
They have folled Mobil in several ways:
Went from claiming PAO to now not disclosing base oils
Mg to overbased Ca
Moved to moly
15 years late in making a world class 0w40