Moses,
Thanks for your response, I hope to pull it apart this next weekend. Still trying to get Taxes done. I had checked to make sure the wheel was tight. Then pulled the brake drum to open it up. I thought that I would be able to just pull the axle, not realizing that the backing plate would need to come off as well. That is when I discovered the zirk fitting and thought that maybe it had the inter seals. A small amount of gear lube came out when I broke it apart, so still not sure if they had inter seals or not. In any event I will mike it before pulling it completely apart and send you the runout measurement . Frankly I was curious if anyone had ever heard a similar sound, from their CJ's rear. The thunking was strange as it did not sound like it was on every revolution. Maybe 2 to 3 seconds apart, weird in my opinion.
Thank Again, truly enjoy my old jeep.
Tim