Originally posted by badkid
I wanna know if people are using MT-90 (GL-4) or 75W90 (GL-5) in their transmission box... and what results you're getting.
I think most people run RedLine 75W90NS in the transmission and 75W90 in the rear diff. Neither MTL nor MT90 are appropriate for the Subaru trans (they are GL-4 as you indicated) but there are at least a few people whom have tried it.
I use Motul Gear 300 in the engine and trans - works great!