What does bad transfercase output bearing sound like?

I just completed step one of my 2wd to 4wd swap today which was to install the 1989 aw4 and 231 transfer into my 93 cherokee . On the way home and during the test drive I noticed a vibration and noise that comes and goes with acceleration and coasting worse at 55mph, alot like a rearend noise but since I did not have a rearend problem before I think it may be the output bearing on the transfer case , I seam to remember a similair noise when a snap ring popped off of my 241 tranfercase in my blazer. Any body have any ideas on my problem?

Yes, that sounds like a rear bearing/bushing. Is your NP231 stock or does it have an SYE? DId you check the oil level? The rear bearing/bushing and seal can be replaced without pulling the whole unit out. U-joints, new?
I'm just throwing some ideas out here.eace:

yes its a stock unit but i dont know the history other than low miles 81k for an 89 model ujoints felt fine but will probabley change just for piece of mind , is a 231 like a 241 in that you take off a snap ring and then the bearing will come off or is it pressed into the housing under the extention?

Pull the tail cone and replace the bearing/bushing and seal. It's not that hard to do. Buy the parts first, it'll make the job a lot faster. Some other items needed, 3 pints (1.5 quarts) Dextron III transmission oil and RTV Black super gasket maker.

yeah, sounds like the output bearing, i replaced mine in November. and you shouldn't need 3 pints (quarts??) of tranny fluid, it will only leak a couple ounces if you're just pulling the tailcone and bearing.