Question - how do you know what was in it? My power steering looks very clean and clear. I'm under the impression it has not been used since last filled. Previous owner says he didn't change any fluids as he never used it and he had it since 2014. Should I assume it is ok to top off w/ the AW32 or ISO 46 or whatever, or should I be worried this is some incompatible oil that I need to find on planet Unobtainia? It just looks like very clear oil and not sure how to tell if it's hydraulic or engine oil in the power steering dip stick.According to the Lube Order, OE/HDO-10 which is 10 wt motor oil. I've attached LO 5-2420-224-12. I'm using 10 wt motor oil in mine and that was what was in it when received.