I've been thinking about switching back to Amsoil 5w-30 in the Stang but I change the oil every 2500 to 3k and I know it can go much longer. So I was thinking about using it in my wifes Accord. Basically, do oil changes on both cars at the same time. Drain mine, filter the oil, then put it in hers. Of course with a new filter. This way I'm not spending a ton on oil that I don't use the full life of. And both cars get a good full synthetic. Anyone else done/do this? What media could be used to filter the oil before putting it in the wifes car?