I recently had a slowly developing metal clanging noise coming from under the vehicle that got louder as I accelerated. It turned out to be the main u-joints. two weeks after getting that repaired I started to faintly hear an almost identical noise but only when coasting around 25mph or less. Even louder when de-accellerating. I crawled under and my main shaft seems fine. The shaft from the transfer case to the front wheels I can turn by hand in park about a good 180 degrees. Is this normal? When turning by hand hard and fast I could hear the clang coming from the transfer case about 5 inches from the rear output. I looked at a print on a different post and the chain would make sense. It hasnt seemed to have gotten much worse once it hit a certain volume a week ago. My concerns are:

1: is it safe to drive like this?
2. How difficult and more importantly time consuming is it to take off and inspect transfer case?
3. What is the most likely cause of the noise if its common?
4. what am I looking at price wise to do myself and/or go to a shop?
5 Will it just fail eventually or will it damage other parts?
6. does anyone want to by this dump off of me?lol

1997 4wd 130k blazer

 

I might have to rent a car in a couple days if I dont resolve this or feel confident enough that it will be safe for a 500 mile trip. Crap.