I have a really strange noise on my 96 impreza turbo, it starts at about 30mph and just gets louder

I can only describe it as the type on whining/grinding noise you get with a binding brake or shagged wheel bearing, but it's not either, I've checked the brakes and it's just passed it's MOT.

There is not a Scooby dealer in my area just now (they went belly up) so can anyone suggest something unusual that could cause this noise?.

SS

 

Could be a broken heat shield on the turbo ??? does it do it if you rev the car when its stationary ???

 

No it only starts at about 25 - 30 mph, I'm still not convinced that the brakes are OK, I had them checked by Kwik-Fit (not ideal, but free) they said they were fine, but I think that the front disks might be worn.

Does anyone know what the minimum thickness of the disks can be before they are replaced, there is a distinct thickness difference between the rim and the main faces where the pads contact.

I think that the edge of the pads are rubbing against the rusty rim. If the disks are still OK thickness wise I might be able to get them skimmed.

SS