My 93 grand cherokee (full-time 4wd) recently had message "service 4wd switch" show on the display panel. So far I have not experienced any signs (vibrations,noises,etc.) indicating any problems. Can someone give me any information on this. I was on another site where it seemed even dealers did not know what to do about this.

look at number 75 on this page I answered it for them.