I am having an issue curently on my 05 STi and I am searching for the solution. I have slow speed wheel shudder when turning the wheel left or right that transmits thru the steering wheel. I don't hear any associated whine or metal on metal or clicking like it a CV or anyhting else, not air in power sterring resevoir etc. The steering wheel "shudders" and you hear a vibration (not metalic or clunking) noise somewhere under the car?
Another slightly scary thing happened this morning when I was on a off ramp (cloverleaf) and decelerating with light braking, the car suddenly (only for a fraction of a second) lurched to the left towards a reatining wall and I almost %^&* my pants.
I did read on one similar thread about the "tone rings and ABS sensors" since this information is fed to the center diff and it could be receiving "bad data" concerning the wheel speeds?