2001 Subaru Outback Ltd noise on slow left turn

Other than the irregular cluckity-cluck sound the left turn is uneventful. I don’t feel or sense any binding or roughness during the turn, although when I do hear the noise my immediate reaction is to back off the pedal. This has been going on for some time. As long as I accelerate straight ahead and then coast through my left turn everything seems fine. I am leaning towards replacing the CV but how to tell for sure which one to replace, the left or right?