Front wheel hub leak

[clamb]

I have a Satoh Buck S470.

It has been owned by my family since mid 1980's and some of the maintenance has been neglected.

Noticing the front hub has been leaking.

Do I need to replace some parts or seals on the front king pins?

Haven't found much info on the front diff, besides thatvit uses sae 80 or she 90 or an 80w-90 gear lube.

 

[clamb]

I see that it is all the same compartment.
There is a drain plug for the diff bell, & a drain on each wheel hub.
Oil looked darker in the wheel hubs than in the bell of the diff. I estimate that it will hold about 2-3 liters of gear oil.