2002 EB 4x4 issues

[skswayze]

I tried searching on my own about this and have not been able to find someone in a similar situation. My 02' EB is quite loud in 4WDHI and 4WDLO but is fine in A4WD. The sound is almost like grinding or rubbing. I have been looking through my Haynes manual and have tried replacing the transfer case fluid and front differential fluid with them not making a difference. After reading in the manual, I am thinking that is may be the front driveline U-joint bearings finally going bad. How likely is this the case? I do not have a bunch of money to start throwing at troubleshooting. I have no problem pulling the drivelines and replacing the u-joints but I do not want to if they are fine. Let me know what you all think about the issue.
Thank you

 

[nvycrmn]

when you say loud, do you mean while the wheels are slipping in the mud or while you are just driving? cuz i have had that problem in my 01 once in awhile when i lock it in and tear through some mud. i get it once in awhile in my A4wd too when she starts slingin the mud.