Brake judder - quick question

[Andrew S]

When braking hard and there is a judder from the front but you cant feel it through the steering wheel, would I be correct in assuming that its pads rather than distorted discs?

I would have thought that bad discs would cause a steering wheel wobble when braking at any speeds.

Perhaps I am just looking for an excuse to fit new discs and buy the green stuff pads.

Any comments welcomed

Cheers

Andrew

[cosmicwheels]

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Andrew. Before spending any money check your tyres for lumps ect .John

[Andrew S]

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Good thinking, will do

Cheers

Andrew

[GDPR]

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Thickness variation of the discs can judder without shaking the steering wheel, so don't rule out the discs just yet.....

[Andrew S]

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Thanks Russ. The discs were standard ones and fitted about 5 years ago. I haven't had to do any serious heavy braking to over heat them and when I touch the brake pedal, it doesn't move up and down which sometimes indicates that the caliper pistons are moving in and out due to warped disks.

Front wheel bearings I know are fine and there is no play as they were recently adjusted.

Will have to take the wheels off and have another look to see how evenly the pads are wearing. I presume the inside pad wears more than the outer as it touches the disc first each time and then the compensating pressure transmits to the other side to apply the second pad. May be wrong on this.

Thanks again

Andrew

[redstag]

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Thanks Russ. The discs were standard ones and fitted about 5 years ago.

That's how long mine lasted before I had to replace them due to judder. I was very disappointed that new parts should last such a short time.



Pete

[Andrew S]

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Interesting Pete

I appreciate that the green stuff pads will shorten the life of new discs, but I would rather have that and good brakes.

Has anyone fitted the groove discs or the cross drilled ones and noticed a big improvement?

Andrew

[colin hanney]

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HI Andrew,you dont say how long ago you fitted the pads,it's possible it may be just one pad sticking or a slow piston seizing and pushing from one side.Just a thought hope it helps,Colin H.

[Andrew S]

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Hi Colin, I fitted the pads at the same time as the discs about 5 years ago.

It could also be air in the system thinking about it or would that make them pull to one side, mmmmm, will have to think about this again.

Thanks for your suggestion

[dasadrew]

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I think that air in the system would be the last thing I would look at.

Brake judder can sometimes be hard to pinpoint and, in my experience, is only due to a brake system problem in 50% of the cases. Especially under hard braking, a lot of other components come into play.

Apart from the obvious check of the brake system components:

- piston sticking
- caliper bolts tight
- rust rim on disc cleaned off

the favourites are:

- shock absorbers (a classic cause of vibration under load!)
- suspension and anti-roll bar bushes
- wheel balance
- track control arms
- the rest of the front suspension!

On my Escort, I forgot to tighten up the caliper bolts on one side and (thankfully) was doing a few runs to set up suspension and tyre pressures. After a few runs including hard braking I went to reverse into the garage and the front wheel locked up. On looking closer, the caliper bolts had dropped out and the caliper was loose on the suspension arm and had jammed the wheel. Despite this, the braking performance was fine, symmetrical, and without judder or weakness!!!! Just goes to show how much the brake system can be out without it making a noticeable effect.

A few years ago I had a judder which I traced to a stick-on wheel weight which had flown off the wheel!

[Andrew S]

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Thanks, will add this to my check list. As you say suspension as well. The part that I am questioning is why when I get the judder, why do I not feel it through the steering wheel? I suppose the brake system tightens something up and is stopping it from moving.

Thanks

Andrew

[Klaus Schlueter]

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Andrew S wrote:

Has anyone fitted the groove discs or the cross drilled ones and noticed a big improvement?

Andrew

Hi Andrew

Last winter I fitted EBC groove discs and Green Stuff pads. Have done some thousand km since. Good breaking performance with 300/310 daN which is very close to my Subaru Forester with 320 daN. Impronement? Yes I think so asI reached 270 daN with standard discs and pads when new.

Klaus

[Andrew S]

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Thanks Klaus, that is quite an improvement and if I have to replace my discs, this maybe the way I will go.

Where did you buy your discs from?

Cheers

Andrew

[Klaus Schlueter]

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Andrew S wrote:

Where did you buy your discs from?

Cheers

Andrew

From Rimmers with the 15% discount action in January. (Discs + pads 199 Pound St.)

Klaus

[Andrew S]

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Thanks Klaus