There is no level or filling plug. If refilling an empty an box, I think that 2.7 litres is currently recommended. Fill through breather hole, with tube and funnel. (I have yet to attempt this.)
As to oil spec I plan to use SAE 75W/80 API-GL4. GL5 was reccommended by Fiat, but Ithink that has been changed. GL5 has higher levels of sulphur and phosphorus based additives, which are reputed to attack the bronze synchroniser components.
Tha advice that I try to follow with my 2.8jtd (same box) is not to engage fifth gear fot the first mile, if the vehicle has been standing for more than overnight. Fifth gear is only splash/drip lubricated from the main box. Allow time for the spashes to be collected and to drip onto the fifth gear assembly.
