This request is for a 93 DSM (Eagle Talon TSI AWD Turbo/Mitsubishi Eclipse GSX/Plymouth Laser). If you weren't already aware, these vehicles are generally heavily modified and for performance use. This project is the opposite. It will see stock boost and light duty. The objective is maximum fuel economy as opposed to my other regularly tracked DSM. The stock spec per the owner's manual is: ""Hypoid gear oil, SAE 75W/8OW conforming to API classification GL-4 or higher" I'd like to stick as closely to this specification for this project. I need just a quart of something or other. I have a quart of MT-85 (GL4) laying around, MTL (GL4 seems to be 75-80), and Pennzoil Synchromesh. I think that the MTL is closest to the spec I am looking for, but wouldn't a GL5 be more slippery? What about the Pennzoil Synchromesh? I know that the additives won't help in a T-case, but would they hurt anything? That is the lightest mainstream fluid that I can think of that is still somewhat generally purposed. Still none of these are "hypoid" gear oil as far as I know which still has me a bit worried. Redline's site states "MTL, MT-85 & MT-90 are not for use in differentials with hypoid gears" P.S. - Here is a description of the T-Case setup for the racing world: "89-94 DSM: The 89-99 DSMs used a spiral bevel gearset in the transfer case. The recommended oil for all transfer cases in the Mitsubishi DSMs GL-5 90w Hypoid gear oil." http://www.teamrip.com/transfer_case_hypoid_gear_oil_recommendation_info.html Thanks for any input!