I'm thinking about switching oil brands in my sled so I'm not paying quite so much $$$. Is it going to damage anything if I switch from Amsoil Interceptor to a non-synthetic? I've heard lots of peeps say you can't go back to non-synthetic after you've ran synthetic. Is that true? If so, why? I hear great things about that Castrol 2T snowmobile oil, and it's about 1/3 the price of Amsoil. If I switch, am I gonna ruin anything? My brother made the switch in his M8, even ran half a tank of Amsoil mixed with half a tank of 2T and it's gone all season on 2T now and not given him the least bit of trouble. Any input?