question about oil level in rear diff

[wannabeH3]

so after my water fording experience, i checked my rear diff for sludge, and its ok, however isnt oil sposed to come out of the drain hole? the level seemed to be a 1/4 to a 1/2 inch below the hole... also is it just straight 90 weight? tranny fluid looked good too, is there anything on the front that needs to be checked? and where is it?

2) wheel bearings, how bout these? do they need to be repacked after going in water? how do you do it on this guy?