JUDDER WHEN BRAKING HARD

[TaggyCar]

I have had a bit of judder when braking hard.This is felt through the steering wheel when braking firmly at any speed over approx 45mph. This improved alot when I replaced the steering universal joint but has become really bad the last few days. Pads /Discs were changed all round just over 6 mths/3000 Miles ago together with rear susp bushes.All steering /suspension components all seem ok with no obvious play in them. Front wheel bearings are brand new.
The ride is very smooth at all speeds.
Do I need to replace the front callipers?
Thanks in advance!

[abelai]

Are you sure your ball joints are all good as its common for them to give brake judder when worn.

[slinky2000]

I was gonna say warped discs but you say you've changed them. Did you change all of them?

[abelai]

I have to say I have never ever come across an actually warped disc. Discs so thin the vains showed through and made it judder yes, pads jamming in carriers and bouncing yes, discs fitted with crap behind the bells making them not run true and even cracked discs but actually warped is a bit of a myth these days. I've parked up with smoke pouring of my pads and discs totally blue the pads were shaged and just crumbled apart but the discs where fine.

[fuzzy]

try taking your calipers apart to see if they are operating freely as they should. the carrier may need greased .

[TaggyCar]

Thanks so far fellas.
I dont believe the ball joints are gone-there is no noise and theres no movement.
Yes all discs were replaced by reputable garage(previous owner) so I dont think there would be any crap left on backs.
I had the callipers off when I did the front bearings a couple of weeks ago and cleaned /greased pins.
I havent had rear callipers off.
Although the vibes are coming up through the steering wheel from the front, could it be the rear callipers?

[siddiqi1]

im getting this juddering to.now i know as a fact that my front drivers side was seized,my mech fixed it but i too oftn get the feeling its seized again,i would check your fronts again.

I to had al discs and pads changed with new Oe fluid and goodridge lines

Abs maybe

Saboor

[TaggyCar]

Ive still got this problem.
Sometimes it is worse than others.
My mechanic mate drove it and was sure it was some sort of front bush/joint problem and not calliper/discs however the car flew MOT last week and tester didnt even give advisories for these.
I read somewhere about faulty abs sensors activating too soon and causing similar problems.
Could this be an abs problem or should I still investigate calliper/disc/bush/joint problem?

[BadDave]

I had this ecently
My outer balljoints needed replacing(changed them
Also noticed that the rubber bush in the tie rods(from ARB to wishbone) were shagged
Changed these and the problem went away

Just a thought

Dave

[tomtomiS]

could still be a warped disc... its not uncommon for new parts to fail

[fastdiablo]

If it was from the ABS any shuddering should come back through the brake pedal and not the steering wheel, more likely bushes if the discs have been changed but dont rule them out completly, only IMHO . . .

[AlpineAde]

Rotor run out? Tyres need balancing? Seized brake caliper? Poor surface condition on the rotor?

All would result in vibration/judder.

I'd get your mechanic to check for runout. Basically....was the rotor installed "true". A dial gauge will tell you.

Here's something interesting I grabbed from the EBC site FAQ (I know it deals specifically with Sports rotors/Pads but what the hell! Worth a read):

"Why do rotors suffer vibration after 3000-4000 miles and how can EBC be so precise in this mileage estimate, surely it cannot be the same for every car???????? … this is a common question.
The reason the mileage is more or less the same for every car where vibration occurs is that the problem develops OFF BRAKE or when you are driving without applying the brake. The more freeway driving you do the more easily this can occur. The excess runout mentioned above caused in 90% of the cases by bad fitting and not checking for runout (and the other 10% due to a hub not running true such a car that has impacted a curb at some time) … causes the pad to “Kissâ€a the rotor gently each revolution of the wheel as you drive. After the above mileage period the pads wear a microscopic thin spot on the rotor and a condition known as DTV occurs. This DTV (Disc Thickness Variation) causes the brake to pulse. A small amount of runout itself does NOT cause vibration but the tiniest amount of DTV does cause vibration. That is why when a rotor is not running true the car does not exhibit vibration in the first few miles and this explains how it shows up later (3000-4000 miles).
How can I cure this vibration problem ??????
Rotors will need to be turned at a machine shop or brake fitting center or replaced. EBC sport grooved rotors can be turned with good results on standard AAMCO brake lathes. If too badly scored or worn some rotors will have to be replaced. New pads will ALWAYS be needed.
Before taking your car to the shop, check if the vibration is coming from the front or the rear to save costs in unnecessary brake work. Generally vibration under braking that can be felt through the bodywork or seating of the car is a problem on the REAR brake and vibration felt on the steering wheel is related to FRONT brake problems.
What are the best pads to prevent or limit brake vibration????
Any good quality pad with a high thermal conductivity will reduce the chances of vibration both due to DTV as described above or vibration at speeds due to what we call thermal shock. Thermal shock is common on European cars and all pads in the EBC range are especially good at reducing vibration. Our online catalog recommends the minimum grades for your car and shows options."

Hope this helps.

[TaggyCar]

Im running out of options :-
I have cleaned up callipers and pistons, front wheels rebalanced and no noticible change.
Could this be a problem with the steering rack or column.
If I give in and decide brakes are the problem, should I replace callipers/pads first , try it and hold off doing the discs or should the lot be changed to avoid re occurence?
I have spent alot on her the last few months and thought brakes were done. I want the problem solved but dont want to replace bits that are fine

[pnd]

i have had this problem recently tried everything including discs pads wheel balance new tyres and control arm bushes turned out to be sticking callipers. its a pain but thats old cars for you its one thing after another

[daimlerman]

When I had this problem I traced it to a shagged N/S whishbone bush,the whishbone was moving about under braking.

[Brianmoooore]

but thats old cars for you

That's lack of maintenance for you!

[kevin316i]

I'm watching this thread with interest as I'm on my third set of front brake discs and pads since I bought the car. The last two sets were original BMW items. I put me fitting the first set as the reason for my brake judder but the last set was fitted by a professional, so I'm going to get him to replace the front left bearing (other three replaced) and check the suspension over to see if there is some worn components causing this. Starting to get annoying and expensive at ┚¬180 per set of discs and pads...

[TaggyCar]

So are you still on the same callipers Kevin?
Did the brakes judder immediately after changing or did they gradually get worse with wear?
I cant see how fitting callipers and discs yourself could be any different from garage?
Im going to remove discs and check that rear faces are clean(although thought they were fine when removed for new bearings) and if that doesnt solve problem then I guess its new callipers!

[pnd]

but thats old cars for you

That's lack of maintenance for you!

i don't want to argue with someone that kmows way more about these cars than i do but how can changing all of these things be lack of maintenance its just with old cars sometimes it takes a while to get to the faults as there are so many possibilities. I know we disagree on this but I have found that these days even a minter and mine is honestly about as good as they get takes a lot of maintenance maybe a high miler would be a better bet as so much would probably already been changed with mine i am just replacing the original parts in many cases which is impressive as they are now twenty years old but its still time consuming and costly.

[kevin316i]

Yes, I'm on the same callipers since buying the car. The brakes were fine when I bought the car but I had the discs replaced as they were well scored and my original mechanic thought they would not pass the NCT(Irish MOT). These were aftermarket discs from ECP and a short while afterwards I started the get judder. It was barely noticeable at forst but got worse so that you had a definite wobble in the steering wheel at about 40-50 mph and under this speed it was less intense. I got front suspension arm bushes replaced and this seemed to help a little but not alot. Putting the problem down to aftermarket disc quality I bought and fitted a set of original BMW discs and pads. Things were fine initially, but the brake judder returned again, starting slightly and getting worse. I was getting some other work done on the car by a new mechanic and he thought that maybe I hadn't cleaned the hubs well enough when fitting the discs and he fitted another set of original BMW discs and pads. Again these were fine for a while but the judder is back. However, it seems to kick in at a slightly lower speed(30-40mph).

I'm going to get him to check callipers and all suspension components and see if there are any worn components. The left front hub hasn't been replaced yet so I'll get that done anyway and get another new set of discs.

The guy I use is pretty good so I'm hoping he'll get to the bottom of the problem without having to replace a load of parts

[TaggyCar]

*********************************PROBLEM FIXED!(Hopefully)**************************************

Just fitted new front discs and pads(OE Parts).The judder when braking heavily which was getting really bad has gone and is super smoooth.The old discs looked fine -only 12 months old-although I think they were aftermarket.Pads had hardly any wear-virtually same thickness as new. Still got a very slight vibration 40-50mph(balancing) which I will get done.
I will be watching very closely for the juddering re-appearring and will be changing front callipers if this happens.

Thanks again for all the advice on this problem!

[insertnamehere]

Glad to hear you got it sorted, but did you read that EBC bumff posted earlier in the thread by AlpineAde? Might be worth getting a DTI on the new discs before you drive too far & make absolutely sure they're running perfectly true in case this is what caused your previous discs to go like that... (was your mileage on those discs similar to that quoted in the info?)