Brake shudder

Akom

Hi

I've just fitted 2 new front brake discs and pads on my DW's Astra as the old discs were worn and i now have some serious shudder, coming through the steering, when you touch the brakes. Its speed related.

Have i installed something incorrectly or could i have a warped disc?

I installed as per Haynes manual instructions. If it is a warped disc how can i prove it?

Any help and advice would be gratefully recieved.

Regards

Akom

bengalknights

Was new pads fitted at the same time? It could possible mean you have uneven pads if there still the old ones.

Joseph_Bloggs_2

bengalknights wrote: »

Was new pads fitted at the same time? It could possible mean you have uneven pads if there still the old ones.

the post above your's makes it clear

Joseph_Bloggs_2

I'd check carefully everything assembled correctly first.

Try spinning the hub with the wheel off to see if disc is obviously bent.

GlynD

If it's a warped disc you'll feel it on the brake pedal if you brake lightly at low speeds. The pedal will oscillate with the high section(s) of the faulty disc. Strangely enough it could be as simple as a balance weight dropped off one of the road wheels. Might be an idea to take it into a Kwik-Fit style emporium and see what their opinion is.

Akom

Thanks for your interest.

The discs and pads on both front wheels were replaced at exactly the same time with new parts.

I have removed the discs again, cleaned the hub on which they sit with a wire brush and re assembled. There is no obvious sign of them being warped yet when i turn one of the discs by hand there does seem to be and area where it nips the pads slightly (very slightly) more. I guess when you're travelling over 40 mph then you only need a slight warp to course shudder.

Looking at it i cant see how you can assemble it wrong as it's quite a simple job, but then again i'm not an expert or experienced hence why i'm on here.


What are the chances of getting a new faulty disc?

Thanks again for your help.

P.S Thanks GlynD. I think if it was the balance on the wheels then i'd have the shudder all the time. The shudder only happens when you touch the brakes. Just looking for other reasons why it might happen as i dont want the supplier laughing me out the shop cause i made a mistake.

GlynD

I don't think you've refitted them wrong going by what you've described. It does sound as if you have a high point or warp on one of the discs. Yes, you could have been unlucky and been given a faulty disc, in which case I'd just take it back to them but it wouldn't do any harm to have confirmation from a mechanic.

flashg67

A simple 'run-out' gauge will be able to tell you - usually have them at most garages and fast-fit type brake centres

gilbert_and_sullivan

Meticulous cleanliness required between the disc and hub, have you really got every nitty gritty bit of rust out, if there's a grub screw holding the disc on only lightly nip it up, it's not there to hold the disc on, only to stop it moving once the wheel is removed.

Double check you have fitted all pads the correct way round, i know it's too late now but i only dismantle one side at a time, more important this with drum brakes which can be murder to remember the routes of every spring and clip.

The number of times all 4 pads look identical and then you discover a slight difference between them and they have to be fitted a certain way round.

Double check everything again.

Did the old discs come off OK, you didn't hammer the hell out of it did you?, bearings can be damaged by such things despite most people's belief, do the hubs spin freely and quietly with the pads away from the discs?..push on the hub as you turn it, all smooth?

Slight grab spot when turning the discs by hand once the brakes have been pressed into normal place isn't unusual, so wouldn't worry unduly about that unless it really takes a lot of force to push past the tight spot.

I've fitted hundreds of discs over the years and never had a bad one yet, but, i only buy from a decent motor factor.

Brakes are not something i'd be poncing about with from dodgy auction sites.

s_b

as gilbert and sullivan says ,you people really need to stop buying braking components of internet sites
go to the local factor ask for trade prices breath in if they quote silly

andygb

I had brake judder a couple of years ago, and despite checking the discs and pads (I had fitted them and they were fine, no loose blots, perfect discs), the problem persisted.
I then put the car in for an MOT, and they found two drop links were worn.
They replaced them and the braking was fine.