Hi All 

I'm having an issue with a pulsing rubbing noise coming from my A6 at low speed and brake pedal slightly pulsing when slowing from 60mph  , it's sounds like a rubbing disc, both pads and discs were changed 5000 miles ago , I took off the wheel and spun the wheels and there is a slight rubbing on and off when spinng the wheel , the disc  seems to be harder to turn at one point , took it back to the garage who installed them and they said they look OK.  My question is could it be a warped disc after 5000 miles or could it be a partly seized caliper ? 

Also when it's a very slight rubbing noise , is it ok to drive on this for a while if its a warped disc ?

Regards 

Edited May 5, 20251 yr by Jepor

More likely to be sticking caliper causing grief. Is the brake disc sitting on a very clean hub? Any corrosion on the hub will manifest itself through the brake disc to the pedal. Also rule out worn wheel bearing.

Drive the car for a few miles and coast to a stop. If the disc is getting hot, you’ll smell it and feel the heat. Tell-tale heat spots on the disc will confirm.

Worn wheel bearing will have constant audible rumble in the background around 40-50mph, rather that tell-tale wheel wobble if you lift car and hold wheel at 10 to 2 position. You can raise car, grip the coil spring and rotate the wheel. Any vibration could inducate goosed bearing.

A full brake dismantle is probably required. Are pads able to move in carrier, etc. Are brake sliders seized?

Yes, okay to keep driving, but avoid heavy braking. Depending on the eventual outcome, you may be swapping out pads again.

Thanks for the quick response. 

Defo not a bearing its not a constant rubbing noise , it's like a pulsing sound that increases with speed , i can sometimes get a smell of hot metal after a long journey,  and wheels are warm but disc far to hot to touch , I didn't strip the calipers as its the rear caliper with an electronic handbrake and don't have the confidence to attempt that , so can't tell if the hub was clean or not , but my guess is probably not cleaned by garage , all too busy for that in my local garage . Whatever about the safety side of it the noise is doing my head in .  

On 5/5/2025 at 8:08 PM, spartacus 68 said:

More likely to be sticking caliper causing grief. Is the brake disc sitting on a very clean hub? Any corrosion on the hub will manifest itself through the brake disc to the pedal. Also rule out worn wheel bearing.

Drive the car for a few miles and coast to a stop. If the disc is getting hot, you’ll smell it and feel the heat. Tell-tale heat spots on the disc will confirm.

Worn wheel bearing will have constant audible rumble in the background around 40-50mph, rather that tell-tale wheel wobble if you lift car and hold wheel at 10 to 2 position. You can raise car, grip the coil spring and rotate the wheel. Any vibration could inducate goosed bearing.

A full brake dismantle is probably required. Are pads able to move in carrier, etc. Are brake sliders seized?

Yes, okay to keep driving, but avoid heavy braking. Depending on the eventual outcome, you may be swapping out pads again.

Hey there thought I'd give you an update , noise found , not brakes . Turns out it was one of my tires , I could hear it when my wife drove my car , i put on the spare wheel and the noise is gone , I think there's a flat spot on the tire , or else the wheel is buckled but can't see how it buckled as I haven't hit anything.  I put on a cheap budget tire to keep me going over Christmas last.  Just goes to show cheap tires are so not worth it . 

 

Thanks for your help.

Thanks for the update. The spare wheel has solved the noise, but can not explain the hot disc. Is the opposite side just as hot?

No both discs hot to touch,  so don't think that's the problem  , when i took off the wheel and rolled the wheel along flat surface you could see the wheel wobble as it rolled , but the question is what caused the tire to lose shape that much , tie rod ?  Or just a poor quality tire ?  I notice there is a slight clicking when turning while driving , which i thought was a cv joint that is due to be changed , so might not be the cv after.  

I am not familiar with the A6 so I can not say whether hot discs are normal, but I doubt it.

As for the deformed tyre, who can say what the cause was after five months of use? It might have been poorly made or it might the result of operating conditions. It rarely pays to buy cheap tyres is all I'll add.

I would have thought that discs would have some heat after driving , this is normal brake friction .

How hot is hot? Yes all discs will become warm or even hot if used a lot, but being too hot to touch is too vague an indication of temperature to say whether something is wrong. However you said you can smell the brakes so I suggest that indicates excessive rubbing.