85w-140 for the rear axle.
I agree with what Kev and HPH said, if there are no axle leaks and the leak from the differential is minor, I don't know that I would bother with tearing down the rear axle. Replace the fluid, and if you feel like making it look prettier, clean off the rust and paint it. It looks like the leak is only from the fill plug (and maybe the drain plug), so just put new crush washers on when you drain and fill the fluid.
If you really want to replace the seals, pack the bearings, and set the axle play, I did all that on mine and have it documented starting
here. I had to do mine because the axle seals started leaking soon after I got the car moving under its own power.
This Post was from: https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=271813