Slightly off topic, but my power steering system called for Mercon. I used this fluid, could there be any side effects? I would think not, but best to find out now before its to late.
Have done several pull and fills from power steering resevoir using M1 ATF both old and new and never noticed any difference one way or the other. Fluid looks great. Each time I suck fluid from the transmission pan I also suck the power steering and refill both.