Just did a brake job on the front.
Front Pads were down to NOTHING. Need rotors at this point, but not gunna worry bout em til later.
Then I checked out the drums, and those seemed fine. Lots of extra pad left. Didn't replace em. That's for another day. Although, when pulling off the brake drum on the right rear, the drum was saturated with some type of oil. (guessing diff oil) Cleaned up the drum with some intense brake cleaner, so its mighty clean now, but the passenger side rear axle is still pretty wet. It's not dripping at all, so I'm not too worried. I'm assuming it's a seal that's gone bad, but I'm not sure. What do you guys think?
Here's some pictures from the job, sorry I didn't include any of the oil mess.

Rear axle could be either brake fluid or if its gear oil it would be a faulty inner axle seal. Not to terrible to change, you can download the factory service manual from a link on the top of the classics forum.

Check your rear breather. If its clogged the expanding air/oil inside will push out a seal. Cleaning it out man solve the issue, but thats a long shot.

Thanks I'll check it out. But I can't find my FSM.. The page says you have it! PM me and I'll give you my email

Its its gear oil....its an axle seal.....if its brake fluid.....its wheel cylinder. If you don't know the difference...look up you tube for wheel cylinder replacement. That would be my guess.

I know for a fact that it's diff oil. Definitely not brake. I just was asking what kinda repair I'm looking at.

there's also no real purpose in replacing the wheel cylinder if the brake pressure is uneven though IMO

Pull the wheel, disconnect the brake hard line and ebrake cable. Four bolts hold the axle shaft to the axle tube, pull them and yank the entire brake drum and axle assembly out of the axle tube. It'll be heavyish, and slick with gear oil, so don't drop it. Set it aside and pry out the old inner axle seal from the axle tube. Install the new one. Reverse the process to put everything back together.

Don't let the axle shaft rest on the new axle seal while you're sliding it into the truck, or you could damage the seal and cause another leak. Now would be a great time to replace the brake shoes and clean out the inside of the drum really well (beware of gear-oil-soaked asbestos!).

Also, this thread would be tons easier to read if you'd put a line break between the pictures in your first post so they don't stretch off to the right for infinity.