[Pixies dad]

thanks for the reply. I have checked with all known GM parts suppliers and they have all shown both part numbers, yours and mine as NLA (no longer available). Even got so far as ordering my part but it was out of stock. GM used this isolator on almost all vehicles from late 80s to mid 90s. So back to the issue: does the auxilary fan have an imbalance or should it run smoothly? Has anyone had to fabricate an isolator?