I got the bosch alternator pulley kit from ECS that seems pretty complete so am hoping I am good on that front: As to why I have to replace the pulley, the pulley on these alternators is clutched and said clutch goes bad. Symptom being a perfectly fine charging voltage but a chattery sound tied to the alternator light flashing on the cluster. Did a ton of research on here trying to diagnose and this is what I've come-up with as a starting point.
Pros: complete kit, cheap endeavor
Cons: clutch goes bad, chattery sound
