juddering when braking

[bigsteworld]

I have an issue where it feels like my ABS is stuck on. Whatever speed I’m doing, whenever I touch the brakes I get that stuttering up the steering column like when your ABS kicks in. No lights come on to say it is ABS just that mechanical judder. Seems to be quite strong around 20-30 mph, but does it al higher speeds too.

I had the brakes checked and apparently they’re fine but it makes for a very uncomfortable ride.

It’s a 2016 Avant, and I don’t have an appetite for randomly changing parts until I find out what it is.

Any ideas?

[audia4b5kev]

warped disc   or brake hanging on   but more to be warped disc  

[bigsteworld]

I thought that too, but I took it to the garage and they reckoned they’d checked them and they were fine.

It seems better initially but gets worse as after a bit of use, like when they’ve warmed up. Does that sound like discs?

[JMKC82]

Hi Steve,

you've mentioned the steering column, but how does the brake pedal feel?

From my experience, when the ABS kicks in, the brake pedal judders really hard, not the steering wheel / column.  I could be wrong??

Thanks, Joe

[bigsteworld]

yes, the brake pedal does judder a lot but it rattles up the handlebars too.

I was going to try to actually make the ABS kick by skidding on a dirt patch of something. Find out if it is ABS or if that is even worse (and the light comes on).

I had to do a 300 mile drive yesterday and it was awful, maybe a bit dangerous on the motorway.

 

[Magnet]

Hello Steve,

’I’ve had the brakes checked and apparently they are fine’. 
By who Steve, and with what equipment? 
To me, this sounds just like a (severe) brake issue associated with the discs, pads or caliper/s, and I would want to eliminate all of these before getting into the more involved suspected ABS problems. 

Has any work been carried out on the brakes on this car in recent times? 
Kind regards,

Gareth. 

[bigsteworld]

I’ve had them checked at two places now; National Tyres and Kwik Fit (only because they offer a free brake check).

Both said the same, there’s nothing to see but definitely something is wrong.

At high speed I’ve noticed it’s worse when braking lighly than hard!

And I’ve had a go at forcing the ABS to come on by skidding on a gravelly driveway but I couldn’t make it do it. Even at speed I couldn’t force a skid.

[Magnet]

Thanks Steve,

So to me, National Tyres ( Halfords) and Kwick Fit have done a free visual check and cannot find anything wrong. That doesn’t in any way attempt to explain what is actually wrong, and fair play, they are unlikely to do that for nothing. 
First port of call would be to get all brake disc  ‘run out’ carefully measured with an accurately set up dial gauge. This will tell you whether the discs are running true or are warped/ not correctly seated. 
If they are running true, then the calipers have to be carefully examined … and so on. 
Kind regards,

Gareth. 

 

[bigsteworld]

Update - I got a bloke off a mate who goes about in a van and does car jobs on your drive. Nice lad, very polite and knowledgable. We went out for a spin and he said "that'll be warped discs". I was fed up with it so just agreed to have him change them (and the pads) £300. It took him an hour or so with his trolley jack and pneumatic wrench. All good! Thanks very much to young Ryan from Middlewich  🙂

But WTF are National and Kwik Fit doing? Total timewasters!! I could have had this fixed weeks ago.

[Steve Q]

Glad you got sorted 🙂

[Magnet]

Thanks Cheshire Steve,

I don’t think you can really criticise National Tyres and Kwik Fit too much in this situation, where I guess they were conducting these inspections free of charge. 
Sounds you have found a reasonable fitter, and let’s hope and trust that the issue is now resolved and doesn’t return. 
What brand of discs did he fit as a matter of interest? 
Kind regards,

Gareth. 

[bigsteworld]

I think he said Delphi, I’d never heard of them and was hoping for Bosch as I have heard of them (I’ve got two Bosch drills). He said Delphi or Brembo were alright. They were just over £100 each.

Don’t know about the pads.

[Caffrey]

Hi,

I have this exact same issue, had it for a while. The car is fine just around town on short runs etc but once we're on the motorway touching the brakes lightly I'm getting a judder which can be felt in the car by the front passenger. Put my foot hard on the brakes and we're fine, car stops but that touch to slow down  - keeping to 50 in the average speed bits for example where you're just touching the brakes is dreadful.

I had the problem prior to the MOT, garage couldn't find a problem and it sailed through the test.

Look forward to anyone's thoughts

[Steve Q]

Have you considered this: 

 

[Caffrey]

I saw this post earlier during my search. I'll take a look - may as well get the discs clocked at the same time.

Thank you

 

[nitch]

Caffrey, have you managed to get to the bottom of this? I still get the same problem just braking lightly at 40+ speeds. New tyres all round. Had the discs checked by the garage that services and mots my car and they reckoned they were fine but will ask them to check again. The judder does feel like something is loose but the second you brake a bit harder, it's fine. 

[Caffrey]

Nitch, that's exactly the same symptoms, mine also gets worse the longer I drive so it gets really bad on a motorway journey. I therefore think it's the discs as heat must be playing a part.

Having it all checked in two weeks, will let you know.

[Pan]

This can be caused if the car sat up for a while, you end up with rust and forming unevenly because of the brake pad. Or if you brake heavily and leave your foot on the brake the pad can imprint into the disk.

It's hard to spot by eye but it doesn't take much of a line perpindicular to the disk travel to cause a vibration. You will feel it mostly in the steering wheel shaking(on hydraulic steering at least) and through your foot.

 

[Caffrey]

On 2/10/2025 at 7:30 AM, nitch said:

Caffrey, have you managed to get to the bottom of this? I still get the same problem just braking lightly at 40+ speeds. New tyres all round. Had the discs checked by the garage that services and mots my car and they reckoned they were fine but will ask them to check again. The judder does feel like something is loose but the second you brake a bit harder, it's fine. 

Nitch,

Fixed! Had a long motorway trip slowing down at 70 thought the car might shake itself apart! Got it on a rolling road discs all over the place, new discs on the front and pads, smooth as a babies.....