I also have vibes over 70. Replaced the rear tranny mount, tension rods and had wheels balanced and alligned just to make sure, ( I didn't want to have to take the car to the shop to have it switched again if it wasn't 100% certain it was the shaft) but it is definitely the shaft.... How did they work it out with you guys? I don't want to give up the performance gain and will probably call Powertrain tomorrow.