I have the same problem with the front vibration at around 60-80 mph. Replaced all bushings, balljoints and shock absorbers in front suspension. Vibration decreased around 70% but is still there at the same speed. I was wondering if maybe, the shaft is my culprit. So I took it to the freeway and ran it to about 85 mph then put the gear to neutral, vibration is still there at the same speed. So, I can conclude that the shaft is not causing the vibration, correct? Would the accell cause the car to vibrate when the vibration seems to be on the front? More follow up info: front vibrates but steering wheel is smooth (does not shake). Please assit. Thanks.