Hi. Simple question...
The rear bearing hubs are lubricated by their internal grease and not by the rear axle oil. Is this right ?

 

That is right...unless you like sitting on the side of the road waiting for the tow truck because you guessed wrong about that and didn't grease the bearings and they burned up and failed and seized and broke. I'm sure you get the idea. No, of course that wasn't me.

 

For Discos, there is a seal between the two spaces. That seal can leak, so sometimes they get mixed. I read that the way back Land Rovers (and maybe some military models) did not have a seal there, so used axle oil for the bearings. Tended to be messier when fording streams.

 

My 1963 2A had a seal for the diff oil. Then you could either grease the hub bearings or fill it’s compartment with gear oil. It wasn’t oiled from the diff as many vehicles are.