Was on a 2008 mazda5 118k. I always try to keep my ocibetween 4 and 5k. I just don't see the point of using oil until it's just not good anymore. I thought about leaving the filter on but didn't see a rating for it. I am a little bit if a perfectionist anyways so it would probably just bother me anyways. The oil with this filter was harvest king full syn. (Coastal) I did notice the oil looked surprising clear when I changed it. I feel as if that is not a good thing.