Ok, I am confussed - I have a 1986 Chevy C-10 and in my restoration, I am ready to put in transmission fluid. My transmission is a 1979 TH400 and the dip stick says to use straight Dexron, but my 1986 owners manual says to use Dexron II. Common sense tells me to use Dexron, but what is the difference between the two?