what's the best gearbox oil?

[petrolhead]

for a RS2000 4 speed box. Haynes manual recommends SAE80 but the way I see it the gearbox oil is going to be in there for a long time so might as well use the best stuff?

 

any recommendations?

[escort new boy]

EP90

[Toby]

I'm a valvoline fan.

[Tom]

Castrol EP80 mate - i've been . .err .borrowing. . . it from work for my cars for years and its great