Hi there! If you send over a DM with your VIN and Ford dealer info, I can look into your concerns on my end.I can’t track down what’s causing the issue. Dealer won’t diagnose because the car has to be at about 85-90mph for it to be present.
I actually tried to feel around under the rear deck (I assume you’re talking under the rear window) and couldn’t find anything loose. With your shock, was there excessive play in it or are you not familiar? Would love to take it to the dealer already knowing the issue so it could just be replaced no questions asked.I had this on mine, more of a rattle and sounded like a loose bolt. Progressively got worse and very noticeable in track mode. Mine ended up being a faulty shock that and was replaced. Took the dealership a while to find it.
Apparently another common issue is the rear deck where the speakers are can cause noise too. Dealership did this for mine as well.
Hi there! I can look into your mustang's noise concern on my end. To get started, could you please send a private message over with the name/location of your local Ford dealer and your mustang's VIN?My rattle is somewhere in the passenger rear seat area & it happens at everyday normal speeds. It seems to be getting louder.