[billwot]

Originally Posted by chipmunk

I have heard of a case where the noise actually came feom a bad clutch throwour bearing and slave cylinder (https://www.caranddriver.com/amp/rev...wrap-up-review). That's why I'm concerned - what if it's not the AC in my case, but something more serious?

Turn off A/C and defrost and see if the sound goes away. Pretty simple diagnostic.