Bad clacky noise coming from center differential especially on left turns and a little on right. Sounds like a card in the spokes of a bicycle wheel. Bought used 115,000 miles and no noise. Had engine oil changed, at one place and a little recall work (anti-corrosion added to brake lines/salt state) at a dealership. Both places claimed to have performed fluid checks of all applicable units. This was before I even knew the car came equipped with a dip stick for the differential. Assumed all was well, then noise started. Took to another mechanic and center differential was dry. Put oil in and was advised to replace entire unit. Very expensive and not really able to afford this. Have had to continue to drive the car for like 6 months now, and even though the noise has increased, there has been no change in performance. I have done some research on the composition of this differential, and was wondering what is actually making the clacking noise. Since there seems to be no performance loss (for now), is it possible just to fix whatever is making the noise instead of the ol' remove and replace the whole unit??? My problem...either no one will be honest with me or they really don't have the knowledge I seek. PLEASE ADVISE!!!