Bit of a conflict on oil advice in this posting.
The handbook for my 2011 +4 BTR axle) states 1.7 litres of 80w140 semi synthetic for the rear axle. When I changed mine 4 years ago, the nearest I could get was Castrol 75W140 Syntrax.
So wondering where the specification of a 75w90 came from? Incidentally, the handbook states the same oil for the whole range of models, so don’t think it’s a typo.