I put in a back-up belt. New. I think its a "Gates". Not sure, but it fit. Glad I keep extras on hand.

I do have an SLS pump leak, so that may have taken out the AC belt. In turn, maybe it flew apart and damaged the alt belt.

Just glad the alt belt is a quick and easy install. The AC belt, not so much.

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1991 560 SEL / 185k miles
1992 750il / 17k miles - project car