Squeaky rear brakes

[doublem_1]

This is doing my head in now. My rear brakes are squealing when mainly reversing or sometimes when travelling below 25mph. I am pretty sure it is just one of them. The sound disappears when the brakes are applied. Went around a multi storey car park today and it was very embarrassing. Any idea what this could be? I replaced pads and discs back in January.

 

[A3Tom]

You might have a seized piston, have you stripped them down at all to clean them up a bit?

 

[doublem_1]

I haven't stripped the callipers no. How do I check if its a seized piston?

 

[jojo]

I haven't stripped the callipers no. How do I check if its a seized piston?

After driving, check if one side is hotter than the other.

 

[S3-Sandy]

I had this a couple of weeks ago, sadly the culprit was the little rubber seal had come off the piston and let all the brake dust and grime into it so had to get two new calipers. Not cheap but it stopped the squeaking!

 

[a3tdi2001]

Before focusing on the pistons I'd tend to check these out first:

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/133873-s3-rear-brakes-shims.html

http://www.audi-sport.net/vb/a4-s4-...iper-guide-pins-do-they-need-lubricating.html

 

[doublem_1]

I'm 99% sure it is only coming from the drivers side rear. WIll be taking it apart and cleaning it all up and reapplying some copper grease etc see if that makes a difference. Noticed however, that it seems to be worse when its warmed up...

 

[eddieantifreeze]

this sounds like either a shim or other noise fix is missing, if this is the case then check if there is any difference from side to side or see if the caliper should have shims (im sorry i dont know for the a3, only thats its pretty likely that they have them).

however you say its occuring off brake so its more likely to be....

It sounds like for whatever reason the pads aren't knocking back like they should, first thing i would look at it greasing the slider and the pins, since its most likely the outboard pad causing the noise. i would also try applying some grease/ copper slip to the ears of the pads (the part of the backplate that hooks into the anchor to locate the pad). possibly worth checking the handbrake mechanism )possibly wind it out) too before taking the plunge on saying its the piston. i only say that because its the most expensive bit and so the last thing i would try if it was my car.

if the pad isnt knocking back then it makes sense that the noise will be worse when hot.

im afraid thats all the advice i have - good luck!

 

[doublem_1]

Thanks for the advice, this will help me a lot!!