I just ordered everything on eBay. Thanks. I’ll hold off and change everything in the spring most likely. But I feel much better now that I know the fix for this mystery noise and I’ll have the parts in hand!
I’m confused, so your saying you added this missing idler pulley?
Yes, I did add the missing pulley, and many other v-10 owners did also; adding removes an intermittent harmonic chirp/ warble or chatter of serpentine. Good Luck