After my overheating debacle, It seems the car has a vibration that wasn't there prior. Nothing any Ford service manager could detect, but I didn't seem to notice it before. It's probably in my head. It just seemed to me that the car used to be turbine smooth right to redline, now I notice some harshness... At around 3k rpm if I floor it in 3rd it shakes the car a bit.

Makes it harder to enjoy the car. I need amnesia!

 

I have similar, I'm thinking our special mufflers are disintegrating. Going to try a set of GT's just to see if it kills the noise.

 

I am having a similar vibration / noise at certain speeds. I have narrowed it down to the driveshaft. In my car if I listen carefully and drop a gear (to 4th) the exhaust is a little louder, but the vibration / noise is still present until I speed up or slow down. It may be a pinion angle issue or just a design flaw with the 2 piece driveshaft. I will be getting a one piece aluminium shaft in the near future and I expect that the one piece shaft will reduce or eliminate the vibration / Noise.