What's wrong with front right wheel?
 

Hi guys,
I'm the guy that bought a $4k porsche 964 from a friend that had no paperwork history whatsoever. Well, I've been working to get it running in tip-top shape and many things are needing repair or replacement.

Here's the work that I had done:
Front rotors machined.
New tires all around.
Tires balanced.
All wheels aligned.

A short time after I had the front brake rotors machined, I started to get a high pitched pulsing grinding sound when braking. It is located on the passenger side front wheel. I decided to change that wheel bearing because I thought that was the problem. Well, after the bearing was replaced, everything was fine for about half a day, then the noise returned.

It seems as though, when I jack up the car and turn the wheel by hand, the rotor rubs against the brake pad. How does this happen when the brake rotor was machined?

Possibilities:
I ruined the new wheel bearing that I installed.
The hub is warped.
The rotor needs to be machined on the hub.
The brake caliper needs to be rebuilt.


Any insight would be greatly appreciated. Could there be anything else that I did wrong that I'm not listing? I'm a fairly proficient home mechanic. I'm trying to figure out what other things I should look for or how I should start troubleshooting.

Thanks!:)

I'm now wondering whether or not I damaged the wheel bearing when installing it. Does anyone know how easy it is to damage the wheel bearing?

Maybe the rotor is warped? Check the lugnut torque and make sure they are all even.

Looking at your list, you don't have brake pads listed. If you turned the rotors, you should have replaced the pads. Also, these symptoms could happen if you machined the rotors below minimum thickness.

It is possible that the bearing wasn't installed properly. Are you sure you completely seated the bearing? If not, then it could allow the wheel to wobble, but it would do it all the time, not just intermittantly. Also, if the wheel is wobbling, you should be able to jack that corner of the car off the ground and tell by watching the edge of the wheel from the front of the car while you rotated it.

It is not that unusual for the rtorto rub on the pad. There is not a return spring to lift the pads off the rotor. As TMC993 commented, did you change the brake pads? High pitched squeeling sounds more like metal to metal contact. Does the 964 have the spring metal pieces that fit between the pads to indicate that pads need replacing. They emit a high pitched squeel.

1. check all four corners sometimes the location / source of the noise is deceptive.

2. are the fender liners all secure with no evidence of rubbing anywhere?

3. did you torque the hub/bearing to spec ? check to make sure it is still torqued to the very large number that porsche specs.
Check the bearing by raising the wheel off the ground (safely and securely) and move it back and forth - any play and there is a problem with the bearing or the hub/bearing bolt. compare it to the other side .

4. take the wheel off and brake pads out . look for anything unusual are the pads ok? Do the pads slide in and out of the caliper and move toward the rotor and back without a lot of force? do the rotors looks good - check for rotor runout or wobble without the pads in.

5. If there is runout check to make sure the mating surfaces of the hub and rotor are clean.

6. 964 caliper use an electrical pad wear sensor no spring metal to squeal.

good luck