Chuck Tator can correct me if I am wrong, but I believe the older Borg-Warners were designed to have the Dextron III and later oils used in them. In 1998 or 1999 they switch to the 75-85 to help with NGR and to be used with the newer Tremec T-56s. I think that Tremic bought out Borg-Warner at about the same time.