Audi A6 Allroad 2015 automatic - Brake Judder

Audi A6 Allroad 2015 automatic - Brake Judder

Author
Discussion

Sibbers2008

Original Poster:

26 posts

190 months

Monday 16th August 2021
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Purchased from a dealer all sound and then slowly brake judder started to appear. Local garage changed front discs and pads, no real improvement, then back discs and pads, all sorted. Since then I have gone to a brake specialist twice to have the discs skimmed and we have now got a new set of performance pads all round to try and reduce the risk of material being left on the discs but this is not working either.
I drive like a nun and so does my wife and like a nun on steroids as this problem has dragged on for the past two and a half years.
Calipers have been checked and they are releasing, so what can it be? Otherwise the car is great and I don't want to chop it in. Running out of options, patience and money !!

efcgriswold

304 posts

39 months

Monday 16th August 2021
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Have you tried driving a little bit like the vicar from cannonball run rather than a nun?

Sibbers2008

Original Poster:

26 posts

190 months

Monday 16th August 2021
quotequote all

Nothing reported back and the brake specialist took everything apart and built it back. Tyres and wheels all good and balanced.
Juddering at the moment is coming predominantly through the pedal, which I believe is more likely to indicate coming from the rear rather than the front ?

joropug

2,566 posts

189 months

Monday 16th August 2021
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I have heard on an automatic that warping can be caused easier due to having to hold the brakes a lot more than a manual.

I.e you do a harsh stop from 70 and then wait at traffic lights the hot callipers are pressed against one area of disc for a minute.

Could be the cause if coupled with a seized calliper as mentioned, rather than you causing the heat from a hard stop, the car is causing it.

Sibbers2008

Original Poster:

26 posts

190 months

Monday 16th August 2021
quotequote all
no harsh braking from 70, hardly been on a motorway in the last year!

MrTrilby

946 posts

282 months

Monday 16th August 2021
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Does it get left for a week or more with the parking brake engaged? I managed to achieve a similar effect to what you describe by leaving our car at an airport two with the parking brake engaged in damp weather. Pads stuck to the rear disk. Lovely clunking noise for a while until they cleaned up, plus permanently warped disks.

Tony1963

4,746 posts

162 months

Wednesday 18th August 2021
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Warped? Really? How?

stevieturbo

17,256 posts

247 months

Wednesday 18th August 2021
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joropug said:
I have heard on an automatic that warping can be caused easier due to having to hold the brakes a lot more than a manual.

I.e you do a harsh stop from 70 and then wait at traffic lights the hot callipers are pressed against one area of disc for a minute.

Could be the cause if coupled with a seized calliper as mentioned, rather than you causing the heat from a hard stop, the car is causing it.
I've heard people say this....but having ran a few automatics daily for a few years...I find it hard to believe.


As for the OP, are you fitting OEM parts, or aftermarket ?

23.7

27,006 posts

183 months

Wednesday 18th August 2021
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Audis o that era have pads that wind back from the disc whilst driving. When your wipers are on the pads 'wipe' the surface every so often to keep them clear of water.

If you're driving like a nun, rear brakes are hardly used allowing corrosion build up.

Get rid of your performance pads, fit OEM or equivalent, drive normally.

Smint

1,711 posts

35 months

Sunday 22nd August 2021
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Pad material transfer is a problem but from the sounds of how you drive is unlikely in this case.

You've had one set of new discs fitted and apparently skimmed twice is that correct? If it were me i'd put new discs all round on it, and make sure they were from a known source and trusted brand, unless the pads are as new or wearing perfectly it will mean new pads also.

Before you do that, have you tried giving it a few hard stops from speed to clean things up all around...paying special attention to not let the vehicle actually come to a halt with your foot still on the brake pedal nor applying the parking brake whilst things are still really hot to avoid pad material transfer, i make that a practice normally wherever possible if for any reason have to use brakes hard.

To check for possible binding brakes when on a long drive if its quiet on the road make for a known layby (uphill gradient) or MSA that you can enter via engine braking in suitable gears and come to a halt without touching the brakes except to bring the vehicle to a final halt, then have a good feel around the brakes and hubs for any undue heat.

Smint

1,711 posts

35 months

Sunday 22nd August 2021
quotequote all
Smint said:
Pad material transfer is a problem but from the sounds of how you drive is unlikely in this case.

You've had one set of new discs fitted and apparently skimmed twice is that correct? If it were me i'd put new discs all round on it, and make sure they were from a known source and trusted brand, unless the pads are as new or wearing perfectly it will mean new pads also.

Before you do that, have you tried giving it a few hard stops from speed to clean things up all around (could be glazing)...paying special attention to not let the vehicle actually come to a halt with your foot still on the brake pedal nor applying the parking brake whilst things are still really hot to avoid pad material transfer, i make that a practice normally wherever possible if for any reason have to use brakes hard.

To check for possible binding brakes when on a long drive if its quiet on the road make for a known layby (uphill gradient) or MSA that you can enter via engine braking in suitable gears and come to a halt without touching the brakes except to bring the vehicle to a final halt, then have a good feel around the brakes and hubs for any undue heat.