Front brake shimmey
 

My front brake rotors have a terrible shimmey when applying brakes. I took the rotors off and had them turned, was careful to clean both mating surfaces to no avail--still a bad shimmey. I bought some new rotors off ebay and installed them--still a bad shimmey. I used a torque wrench to tighten rotors. What a pain. What could be the problem. Actually the new rotors are a little worse. Of course the new ones are a little more abrasive maybe amplyfying another problem. Is it possible to have new warped rotors. Dennis

Yes, indeed, it is possible to have new, warped rotors.

When installing new rotors, you must change the pads. Start new with new.

Uneven pad material distribution on the rotor can also cause vibration when braking.

Was the hub clean when you put the rotors on? I would think that if there were to be dirt or rust on a part of the hub, then the rotors won't have an even surface to mount on and could be mounted ever so slightly crooked.

Look Elsewhere
 

It can be in your steering assembly. Pitman Arm, tie rod end/s and rubber bushings...I would check under the car while having the friend or wife turn the steering wheel...When you apply the brakes most of your front end suspension will try to move and if it is worn then you can get vibrations and think that they are coming from your brakes. I have had cracked rotors and could not find new ones and I installed used pads in very good condition and never have a vibration on a 126. When I got to where I was going I replaced the rotors.