I am using Motul Muti ATF
https://www.amazon.com/Motul-MTL1057...ords=motul+atf
like others said however, DO NOT HAVE ANYONE FLUSH IT, it will cause damage if they use a machine on it, what I did was drain and fill till it became red again., mine was black..... then one last drain and fill and some lubesgard o it. I also put a huge trans cooler on it as well
and well, it drives fantastic, and hold up to my abuse. tbh I would recommend draining the pan and refilling every 20k as these cars do have much in a way of a filter :/