It’s a VW 504/507 approved oil which is a fairly high bar to hit. Plus it meets API SP for those who think it’s important. It’s much cheaper than Mobil ESP that everyone holds in high regard but it also has the latest API SP rating.
I always heard redline had a little over 40% ester and Amsoil SS had over 20%. No idea if that’s acccurate or not. But their VOA oxidation levels may indicate some truth to it. Redline is around 90 and Amsoil SS is around 45.
If a person is willing to pay for a more extensive analysis through Polaris labs, they can tell you exactly what part the metal is coming from. It’ll cost a couple hundred bucks. I know several people that have done this on class 8 trucks. Money well spent considering engines can be upwards of...
Every time I use amsoil in my wife’s Taurus with 3.5 Duratec it has a reddish color to it. I asked Amsoil about it and they said it was normal and is a chemical reaction from the detergents in the oil with some contaminate inside the engine.