My power steering fluid has been a dark grey color since I got my car. (It's also been slowly leaking, but since it took more than a year to go from Max to Min, I'm not really worried about that at the moment.) The other night, I decided to stick a magnet from an old computer hard drive into the PS fluid tank, and after sitting overnight the magnet came out perfectly clean. Whatever is making the fluid so dark, it's not iron. (Of course, for all I know, the steering rack internals are aluminum or something.) Is the PS fluid dark to start with? I kinda figured that mineral oil would be the color of baby oil (clear), since the two are effectively the same thing.