I know this issue has been beaten to death, but since Mercon synthetic fluid is hard to get at the regular auto parts why cant we use Super Tech synthetic tranny fluid Mercon/DexronIII from Wally World. Is there anything wrong with this fluid? I'm due for a tranny oil change soon and I would like to stick with the synthetic since that is what I have in there now. If the knowledgeable minds here on this site say its ok, then I will use it. Thanks in advance for everyones response.