Bleeargh, one of the things that often crops up on forums like this is people writing in asking for "opinions" on highly technical subjects. What value can those personal opinions possibly have compared to the owner's manuals or shop manuals prepared by the manufacturer?
In the case of lubrication, I would give a personal opinion credibility if it comes from a lubrication engineer. Every one my own personal vehicles has a different trans oil specified:
1995 Ford Explorer w/5-speed-ATF
1978 El Camino w/Sagnaw 4-speed-90W gear oil
1971 Dodge Van w/New Process 445 4-speed- 50W engine oil
1936 Chevy pickup w/3-speed - 90W to 160W gear oil(seasonal temperature dependant)
Presumably the engineers who design these transmissions and the factories that manufacture them are very experienced in their particular products and know what suits them best. Being neither a metalurgist, chemical engineer nor lubrication engineer I'll trust the factory recommendations.
Perhaps a herpatologist will recommend snake oil. All of the auto parts stores carry a wide variety of that type of product (Lucas, Marvel Mystery Oil, STP, etc, etc.)
