Sounds similar to a situation I encountered myself a while back. My sound came from my wheel area. What I discovered was that there was a rock lodged in between the rotor and caliper and was scraping across the rotor while I was driving causing an insanely loud screeching sound. Eventually with driving the rock came out but my god that noise was ear piercing.
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|2013 Audi S4|Ibis White/Black|S-Tronic P+|
|2013 370z|PearlWhite/Persimmon|Touring/Sport/Nav|F.I. CBE 18" CF|
|Sold|2011 370z|Gun Metallic|Touring/Sport/Nav|
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