rear diff noise while turing, more a clunk sound.

Is the noise in the rear end of the car or more towards the back of the trans? I'm guessing it's the back end since you can feel it. If so, it's probably the differential but you can check on nasioc or Impreza forums. It could be a chipped gear or something else. Best regards

Thanks, if it was a chipped spider gear would it not also be felt if the right wheel was stopped allowing the left wheel to spin? This is a strange problem and only reared its ugly after the car sat for a year prior to that no noise was heard. At least that is what I have been told.

If it's an open diff then one side will spin really slow and the other fast. But idk all the specs on what came with what. Idk about LSDs and how they divert power..

Here is where I am with this issue today. Now this is going to sound weird but it is true. After reading several Subaru blogs and discussion with different auto tech's, I decided to take the car for a long drive down the interstate, reaching 70 at times, to see what would happen. With cell phone at hand, to call a tow, off I went. It ran perfect with no vibrations or noise. At the end of the trip pulling in a side road and drive way the noise was gone! So for the time being I am leaving this sleeping dog alone. I want to thank everyone who took time to offer suggestions all of them have been a great help.

You are so right! Thanks for your help.