The Castrol Mercon 5 is made for Ford transmissions. When I was a kid it was easy they made two kinds, Ford and everyone else. Now there are litterally hundreds of types, and the original fluids aren't even produced anymore. I talked with Sam the transmission Guy and he said synthetics will keep operating temps lower and extend the life of the transmission. He also said the aftermarket pan from derale would further keep things cool, so I'm not sure where to go with the fluid. Mobil 1 synthetic was also recogmended by him. He did say all the fluids are pretty much made at the same plant, and a lot of what you are buying is a name. I guess I was just looking to hear what you guys use. Probably will go with the syn 1 from Mobil.