Sorry I just got back on the computer. You don't need to use gaskets there. But since your this far I would pull both axles and check how the bearings are.
You get the axles out and check the bearings by feel?
Sorry I just got back on the computer. You don't need to use gaskets there. But since your this far I would pull both axles and check how the bearings are.
I would put it back together and see if your noise is gone. If your bearings are tight and not making noise they are ok.
Those gaskets behind the plates are to keep out brake dust. Seen people silicone them before too, probably what they had available at the time.
The bumpy feeling when you turn the axle is the spider gears turning inside the differential.