anyone know if dexron 6 is compatible with Mits diamond spIII for a 2001 eclipse GT automatic trans

 

valvoline max life dexIII

 

General Motors now recommends dex 6 in trans that took dex 3, so if you are recommending a brand that is dex3, should I assume that it would have similar properties. It boils down to the fact that I can get dex6 for free, but I dont want to shorten the life of a trans to save a couple of bucks on fluid.