I have an 86' Mustang 5.0 Coupe 5 speed. The problem im having is that its making a bad vibration ot higher RPM's like around 3000 an on up. This vibration even occurs when the car is running at idle sometimes. I have put a new clutch and flywheel in it and the problem just got worse to where i can hear a noise coming from the rear of the car. I have even replaced the yoke, and u-joints. I need some help, I have tried just bout everything.