I noticed that I had a leaking axle seal on my 69 Mustang with an open 9 inch rear end. I pulled the axle, but I noticed that the seal in this design is inboard of the axle bearing. What lubricates the bearing? Do I need to put bearing grease in it, or does gear oil go past the seal to lubricate it?
They are permanently lubricated. No greese required. When you buy new ones you will see that they are sealed. For that matter, the old one should be a sealed bearing too.