Brake judder, and it's not warped discs

[JakeR]

Hi Folks, my work nail is a mk 1 Skoda Octavia tdi, and it has a very annoying judder coming through the steering wheel under braking.

I first assumed it was the front discs, so I changed these and it needed new rear discs anyway, so it ended up with new discs all round. The judder went away for a bit, but soon came back. Cue another disc change just in case (fronts only). Again, it goes away, but now it's back, and it is mighty irritating!

Any thoughts on what the culprit could be?

For reference, braking performance is still very strong, and without any pulling to left/right...

Many thanks

JakeR

[steebo888]

out of balance wheels? would be my first guess, then air in brake fluid, bushes on suspension parts. check for play on both front wheels as well and have a good look round control arms, anti roll bars.

Mine had this which turned out to be 1 front wheel out of balance possibly due to a pot hole

[GreenV8S]

Given that it went away when you changed the discs, you are obviously in the right area. Rather than warped discs, it may be uneven disc impregnation by the pads. I hope you kept your old discs, you may find that if you clean them up with garnet paper it cures the problem.

Another problem I've see that can cause judder is a worn balljoint, but I don't see why changing the discs would make the problem go away so that doesn't really fit.

[odyssey2200]

when discs are made there can be internal stresses in the metal which can cause warping when they get really hot.

You need to use a DTI guage to actually check the disc run-out.

You might be better off taking the warped set to a machine shop and getting them skimmed.

There will be a min thickness stamped into the dics somewhere.

[Ballistic Banana]

Very interesting article here on the Warped Disc theory

Clicky Here

BB