Type A and DexronIII/Mercon are 2 totally different things. I have a '64 Ford that uses Type A, that can also use DexronIII/Mercon, but a Tomos is different, because of the cork clutches. You can use DexronIII/Mercon in a Tomos, but the clutches will wear out faster. Heeters says to use Golden Spectro 10w30 2 stroke motorcycle gear lubricant. Spectro oils makes good stuff, but I don't know about it's compatability with the Tomos clutches. I use Walmart 10w30 oil in the transmission of my old 2 stroke Yamaha dirt bike, but it doesn't have cork clutches. My A35 manual says Type A, Type F, or 10w30 oil. Who knows. Peace. Jerry.