V70 Brakes: Brake Judder

[Stone Free]

I'm experiencing brake judder at high speed, which causes the steering wheel to shake (its ok a lower speed) Had the V70 serviced recently & mentioned it.....but seems they aint cured it. Front discs are fine & also had rear discs & shoes replaced.

Any thoughts ?

[ShadeTek]

Sounds like warped or contaminated discs. Is there a wobble under acceleration or decelaration in gear? After a run, are any of the discs or wheels roasting hot?

[JameseT5]

Originally Posted by Stone Free

I'm experiencing brake judder at high speed, which causes the steering wheel to shake (its ok a lower speed) Had the V70 serviced recently & mentioned it.....but seems they aint cured it. Front discs are fine & also had rear discs & shoes replaced.

Any thoughts ?

My brake discs were new in December and I get a little shudder sometimes. Mine is caused by little leopard spots on the discs, or a slight amount of pitting which makes the surface uneven and causes brake shudder.

[RM955I]

Originally Posted by ShadeTek

Sounds like warped or contaminated discs. Is there a wobble under acceleration or decelaration in gear? After a run, are any of the discs or wheels roasting hot?

Sounds like a warped disc to me too. Just because they're new doesn't mean they're 'true'.

Another option is to de-glaze them if there is any possibility they are glazed - a bit of brake cleaner and wet 'n' dry. Having said that, glazing would normally show as poor bite and retardation not a wobble.

I'd also check carrier bolts and slider pins for good measure whilst I was giving it the once over.

[Norfolk Jim]

I had this once before and got rid of it by doing some pretty hard braking from speed.

A chap I knew worked for Ferrodo and said often it is caused by small deposits left after hard braking and sitting at junction with footbrake on.

It appears when brakes are very warm the dust can get attracted to them and when people sit at a junction or in heavy traffic with footbrake on this sort of presses the dust onto the disc and bakes it only slightly; which then under normal braking from speed causes a wobble even though discs are true and not warped.

Some brake pads cause it more than others but all he said was try doing a few bits of really sharp heavy braking from reasonably high speed and see if that helps.....................

I had this problem on my Saab 9-5 Aero only 12 months after new AP Racing discs were fitted. I did as he said and it cleared it. I then had to learn to use handbrake properly as car was semi-auto.

Worth a try - took me 6 goes and ended up with very very hot discs!!!!!! But cleared it in the end

[paul3346]

Bought my xc70 and on test drive, no probs - drove at low speeds. After a while, and speed increased, noticed a wobble on steering and a rumble when braking. Braking was adequate to good.
It is my usual practice when I buy a 'new' car to make sure the brakes are first class. Fortunately, my son in law is a mechanic and took over.
Replaced all discs and pads. One of the calipers was sticky and was sorted. Result was excellent. The excersise was not cheap, but worth every groat!

Paul....

[SonyVaio]

If discs are fine then you'll probably find it is down to a worn bush or similar.

Bottom ball joint
Track rod end
wishbone bushes

Basically there is movement somewhere.

If you feel it more through the pedal then it will more than likely be disc related, if it more through the steering and nothing from the pedal then it will be bush related.

[Jim.F66]

Have to agree with Sony. I had a similar problem on my Discovery and only got rid of it after replacing the front bushes and suspension struts.

If there is any play in the front steering or the suspension system then you will feel a lot of judder via the steering, and this may show itself as judder at a certain speed without braking. In my Disco this showed between 48mph and 55mph, above and below that only when braking.

Drive over some smallish pot holes and see if the front appears to jump more that you would expect, that would be a clear sign of a suspension damper failing..and remember, if it is one of them, you need to do both front ones at the same time...