Outer Limits 4x4 Board

I've tried the search but not really helpful.
Can someone please tell what weight oil to run in the front diff of a 2002 gu patrol wagon.I know its 5.4 litres,but forgotten the rest.

cheers

80W/90 Hypoid

i've run 80/90 or 85/140 LSD depending on what i have in the shed at the time