I just had an ACT clutch installed on my Evo IX MR. After the install, I can feel vibration on my clutch pedal when I just push it down far enough to make the clutch fork touch the throw-out bearing. It's not a really violent vibration, but feels like a massage from a HomeMedics foot massager. When the pedal is fully depressed (ie, the clutch is disengaged) the vibration goes away. When the clutch pedal is released (ie when the clutch is getting back to engagement) I can feel a quiver right at the moment of contact. After a gear shift after WOT, the pedal sticks a little before it pops up. If I put the tranny in neutral, then there is no vibration regardless of clutch engagement. From a high level perspective, there is obviously some kind of misalignment between the transmission side and the crank side. As to what is causing the vibration, nobody knows. The shop that installed my clutch has dropped the tranny and taken a look, and said everything is lined up properly. Also from a high level perspective, while the car is in gear and the clutch is engaged, the transmission input shaft will be continuously vibrating.

I am concerned, and would like to know if this constant vibration will ruin my tranny or the crank bearings. If it shortens my clutch life, I'm not as concerned because the clutch can be easily replaced. Has anyone ever had this problem, and what did you do about it? Thanks a lot!