Unless it's changed over the past few years, the #1 transmission additive used in transmission shops was a product called LUBE-GARD. There are different types available, but in your case I think the RED bottle product would best suit you. Google the name LUBE-GARD and go to their website to see the additives they make for automatic transmissions and the various NEW oils currently being sold/used by the OEMS. I've heard that TYPE F is no longer being made and is very hard to find.
