The final item on my "should fix" was the "hard shifting" on the AOD transmission on my 90 F150. I got the truck 2 years ago, at 63K miles, put 7K miles on it so far. I replaced the transmission filters and fluids (Synthetic Type F, do not remember the brand.) Took the transmission to the local, and best rep transmission-only shop and mentally prepared myself for $1000 in repairs. He checked all the usual culprits, found nothing wrong, in great shape, and we went on a 25 minute town and highway trip where I recreated everything I ever worried about. At the shop, he shook my hand and said that that is how AODs shift. Given that in this recession he passed up a quick payday, I am inclined to believe him. Then,,,,I remembered some ancient threat about "smoothing out" AODs with a specific ATF grad or spec. I cannot find it via the search. Q. IN YOUR EXPERIENCE, What is the best grade/type/spec of ATF for the older Ford AOD transmissions? specifically for smoother shifts. thanks! in advance!