A couple yrs back mine was stuck on my early model A4. Never needed to adjust it anytime during last 40 yrs untill I noticed some forward slippage. Got it free by spraying it with PB Blaster penetrating oil. My problem turned out to be even simpler - loose "U" bolt on the outer sheath of the shift cable clamp. In the end I did not need the ring adjustment and for sure did not like the extra effort reguired to engage the detent with the shift handle.
|