I thought type f has No friction modifiers? thats why its grabs the best. dexron and other trans fluids all have modifiers in differemt amounts to get a certain amount of slip. synchromax surely has modifiers in it to purposely get slip. Just like most motor oils and any sythetic im sure.
I would try dexron/mercon fluids or factory auto fluids like honda or chevy. just a thought to get something to work right and be cheaper then 20 a quart for synchro.