Originally Posted by ka9mnx
Originally Posted by OVERKILL
AMSOIL is a blender, no different from Ashland (Valvoline), Eneos, Royal Purple, Fuchs, Motul...etc. There are very few oil companies that produce all of their product in-house, particularly for all grades. Mobil is one, Shell is another. BP doesn't produce PAO, so any oil grade that contains it, like Castrol 0w-40, is using a base sourced from somebody else like ExxonMobil or CP.
Similarly, additive packages are produced by a small group of players with the two biggest ones likely being Lubrizol and Infineum, the latter which is a joint venture between Shell and Mobil.
AMSOIL's base oils, at least their PAO, I believe comes primarily from XOM. Their additives are likely sourced from Lubrizol. That doesn't mean that Lubrizol or XOM "makes" AMSOIL's oil, they blend the additives and do their testing in-house. There ARE oil labels out there that just resell somebody else's product and do no blending. SuperTech, NAPA, Toyota, Motorcraft, Mopar, Honda...etc any of the OEM brands are blended by somebody else and sometimes these oils are identical to other oils blended for another. IIRC, it was NAPA that was the same as Valvoline White Bottle or something along those lines at one point.
This is the absolute truth. XOM provides the synthetic base and Lubrizol provides the add pack.
XOM provides some, Chevron and others, provide base oils. Look at the tanker cars.....Lubrizol is one of the additive pack makers, but they buy additives from others as well.