Yeah what are some options for after-market, thinner gear oils?
I am about to replace mine soon, after a clutch and gear swap, and just yesterday realized there could be FE benefits from finding a thinner gear oil...
Don't see much out there other than 75w90s, though people say good things about the VW spec synthetic LubroMoly in terms of shift feel.
heres a white paper I just found shjowing comparison of synth to dino 90w.
http://www.redlineoil.com/whitePaper/18.pdf