The awd went to fwd, intermittently at first then quit altogether about five months ago. Now it started making a howling noise from the rear similar to an old truck rear end gear whine. If I hold the speed constant the noise is constant if I slow down it is lower and louder if I speed up the pitch is quiter and higher.

These may be unrelated, but when asking around about the awd quitting, someone said that a bushing in the third member may have cracked. I do some work on cars but I have no idea what a third member is. Help I can not afford a big diagnostic bill now.