I'm surprised that none of you "old timers" have discussed a product called Marvel Mystery Oil!!! MMO can be added to fuel or crankcase to perform the same magic that Darius' father is promoting with ATF. I have no experience with MMO in a car that has a catalytic converter and am not even promoting the product. I have heard through the "old timer" grapevine that MMO is basically ATF but I suspect it may not have all the additives that a tranny might need. The last time I used it was in my 1965 Ford Falcon and it did indeed clean the engine and improve performance. I would use MMO before I would dump some ATF in any automobile.