Red Line MTL 70W80 GL-4 In transfer case and gearbox?

[bstraw]

I have a gallon of this stuff left over from my D-90 and was wondering if I can use it in the 1974 Series III gearbox, transfer case and differentials. Seems like our hosts offer the Amsoil 75w-90, but when I go to the Amsoil page it seems like the Manual Transmission & Transaxle Gear Lube 75W-90 (see link below). So why do our hosts not offer this and is it better? I want to put the best stuff I can in there and am not too worried about cost, any ideas?

http://ww2.amsoil.com/shop/by-product/transmission-fluid/manual/manual-transmission-and-transaxle-gear-lube-75w-90/

[stomper]

sounds like it may be a little thin, given the series rovers call for straight 90wt. most people use 75-90wt because it is more readily availible than the old 90wt. the thiner oil, along with the synthetic viscosity, and I estimate you will get around 800 miles before it all runs out.