Judder, Whilst Under Light Breaking?

[Dan_Harris]

Ok guys I have mentioned this in a couple of previous threads but thought I would start a new one as a bit of a info and will keep it up to date as i get them.

Story goes - I picked up my IS 3 weeks ago today, on the way back on the M40 I noticed quite a bit of violent break judder but only between speeds of 80-55/50mph, the judder didn't pull the either side just gave a lot of play in the steering. The judder is more vicious if i break lighter than if i break heavier, the car was serviced + MOT'd the week prior to me picking it up and all were fine, Last August the discs + pads were replaced, now I don't think it is a disc or pad issue as I have had the car upto 130mph and lightly breaked down to 50mph and from 130-80 there is no judder however the judder kicks in 80-50 again, there is a bit of break squeal at lower speeds but i'm putting this down to the new pads.

I have searched about on the net for this issue and some people have said that having wheels balanced solved the issue, so yesterday I visited the Dr (Tony Bones) at WIM to check my wheel were balanced my o/s was fine but my n/s was 5grams out, this was solved and driving back home the judder was still there. So that's 1 thing off the list.

Now speaking to other petrol heads and the Dr I have had many views + ideas on what it could be, rangeing from warped discs / tracking rods / to a possible issue with the ABS playing up.

Just curious on people's thoughts on here, and I'l also be having the car put on ramps to check the rods + getting the discs checked and shall update as soon as I know, but please feel free to comment on anything that I may be missing :)

<3 in advance

[Parthiban]

It could be warped discs, I've had a similar judder for ages that hasn't really been a cause for concern but is irritating - got it checked out and my left front disc is mildly warped apparently. Going to get it all sorted by the Dr at some point but just haven't had time yet.........

[Dan_Harris]

what speeds do you notice the judder Parthiban? like i say above 80 is fine and below 50 is smooth just in that range it's really bizzare.

[edeath]

I've got the same on mine. I just put it down to a mildly warped disc and will just live with it untill i need to change them - which will be soon. I have also had people tell me that it could be bits of brake pad that have become attached to the disc when you hold the brakes on at the lights for example after some heavy braking.

[Parthiban]

what speeds do you notice the judder Parthiban? like i say above 80 is fine and below 50 is smooth just in that range it's really bizzare.

Haven't really tested it over 80mph, but otherwise tend to get it at various speeds - seems to depend more on the pressure applied rather than the speed of travel.........

[Dan_Harris]

similar to myself, then the lighter i break the more noticeable it is.

[T22DLH]

sounds like warped disks to me.

[Dan_Harris]

ok update folks, just been out in the car and not hammering it but twice tonight i've heard a loud crack (same sound as if a stone were to be flicked up and hit your car) come from the front and i think n/side but defo from front.

Heard it the other day but put it down to a stone as i was on a loose surface, but there are no stone chips on my car :( getting worried now

[T22DLH]

I had the same cracking noise with mine, its the pads moving inside the caliper. i think you can get a repair kit or something to replace the spacers and springs on the caliper

[Dilbert D]

Hi there,

Just had identical problems with my 99 SE. Exactly the same symptoms, judder feeding back to the steering wheel at speeds from 80 down to around 50, but not really that noticeable down to 0. Mine gradually got worse over a two month period. If it is warped discs you may notice a pulsing as the wheels rotate as you come to a stop on a very smooth bit of road as I did.

Anyway, long story short, I bit the bullet and got new front discs and pads from the Lexus dealer, gave the car and bits to my local garage to fit and hoped.

When I got the car back the braking is now totally smooth at all speeds, like a Lexus should be, job done, 219 quid in parts and 60 quid labour. B)

Only thing is that sometimes if I tap the brakes when reversing I get the clunk as you describe but that is just the pads moving a few millimetres in the calipers, but I have read that they all do that <_<

Hope that helps ..

[kallabungo]

Hi there,

Just had identical problems with my 99 SE. Exactly the same symptoms, judder feeding back to the steering wheel at speeds from 80 down to around 50, but not really that noticeable down to 0. Mine gradually got worse over a two month period. If it is warped discs you may notice a pulsing as the wheels rotate as you come to a stop on a very smooth bit of road as I did.

Anyway, long story short, I bit the bullet and got new front discs and pads from the Lexus dealer, gave the car and bits to my local garage to fit and hoped.

When I got the car back the braking is now totally smooth at all speeds, like a Lexus should be, job done, 219 quid in parts and 60 quid labour. B)

Only thing is that sometimes if I tap the brakes when reversing I get the clunk as you describe but that is just the pads moving a few millimetres in the calipers, but I have read that they all do that <_<

Hope that helps ..

I had the same situation as you - except i bought some mintex pads and standard discs for £62 and fitted them myself - i was shocked when the garage quoted a 2 and a half hour labour charge to do them. So i took on the work myself and its surprising how easy they are to change.

At the end of it all the shaking has completely dissapeared...! Job done.

[Dan_Harris]

Awesome, yeah I shall be going the Mintex route. Will have to wait a couple of months me thinks due to funds :P. How long did it take you to replace the discs? Is there any drawbacks to running stock lexus discs/pads at the back and Mintex at the front?

[rig-pig]

same with me i put new discs+pads and it was still there ??

so i checked the rear and there is a slight warp on one disc so time to change them next.

every one thinks its the front but check the rears as well

[bigdave-is200]

Hi i have the same sort of problem but only just changed all my brakes and discs after about a month it just seems to come back they were bedded in ok

i used mintex discs and pads cost a few bob i think fitting is easy but bedding them in is a pain

I have noticed if i pump the breaks the shudder goes away for a little while sometimes its fine others i feel them shaking

if i break light it shudders but if its firm its fine

when i had warped discs it would only shudder at high speeds so i dont think its that

I know its driving me nuts tho as i love my car and hate anything not feeling right

I think one of my pistons is faulty and its just not breaking true

got a mate in leeds who has a pair of calipers for me going to try a few things out if i get any joy i will post what i find

if anyone has any advise that would be great

Thanks Bigdave

[Steviewevie]

I think one of my pistons is faulty and its just not breaking true

got a mate in leeds who has a pair of calipers for me going to try a few things out if i get any joy i will post what i find

It could be a sticky calliper, that seems to be a very common problem on the IS200.

[nigel883]

I had the same problem with judder under braking on my GS300 and the simplest way to find out is to take your car into your local MOT station and ask them to put it on the rolling road. If you have a warped disc, it will show up on the display as the needle will go back and forth. Dont forget to do the back wheels as well as the front. In my case it turned out to be just one disc on the nearside, but always advisable to change in pairs, which I did along with new pads and this was carried out 6 months ago and no problems since.

[rig-pig]

most brake test equipment is digital now. and thay run to slow to show warped discs

[bigdave-is200]

Just popped to my local lexus dealer and spoke to one of the mechanic's i have been informed on older reg is200's its common for the caliper to develop a fault

and this fault fits all of the symptoms and makes alot of sense to me

so i guess its buy the repair kit or get some new or refurb ones got the price for the repair kit about £60 pounds

would be good if anyone knows where to get these kits at a cheaper price

anyway im going to pick these calipers up of my mate soon clean them up fit them and will post my results

BIGDAVE

[Dan_Harris]

Hmm will be interested to know the results, I'm fairly sure regarding my issue it's definately a disc that warped.

[Steviewevie]

Hmm will be interested to know the results, I'm fairly sure regarding my issue it's definately a disc that warped.

But why has it warped ? If it's because of a calliper problem, then a new disc will just warp again in time.

[Dan_Harris]

very true, but seeing as the disc is near new I would put it down to just a defect disc to start with (also replacing front discs+pads) is a hell of a lot cheaper than a caliper setup ;)

[muddyell]

I have this same problem but only since i have changed my front pads. When changing the pads it was clear that the passengers side lower caliper carrier had seized and the pad now sits slightly off so not flat. We put it down to that as i didnt have this problem before changin the pads.

After reading this i am not sure anymore. Maybe upgrading the discs is a good idea if they tend to warp and maybe new calipers if they are crap too

[imperial1952]

Hi there,

Just had identical problems with my 99 SE. Exactly the same symptoms, judder feeding back to the steering wheel at speeds from 80 down to around 50, but not really that noticeable down to 0. Mine gradually got worse over a two month period. If it is warped discs you may notice a pulsing as the wheels rotate as you come to a stop on a very smooth bit of road as I did.

Anyway, long story short, I bit the bullet and got new front discs and pads from the Lexus dealer, gave the car and bits to my local garage to fit and hoped.

When I got the car back the braking is now totally smooth at all speeds, like a Lexus should be, job done, 219 quid in parts and 60 quid labour. B)

Only thing is that sometimes if I tap the brakes when reversing I get the clunk as you describe but that is just the pads moving a few millimetres in the calipers, but I have read that they all do that <_<

Hope that helps ..

Picking up on your comment "If it is a warped disc you may notice a pulsing as the wheels rotate as you come to a stop on a smooth bit of road".

This was the problem i had about 3 months ago and i also thought it was a warped disc at the front. I then proceeded to strip the N/Side front first and checked it for warping/runout with my trusty D.T.I. and found it was well within the 0.002" (two thousandth of an inch) tolerance zone quoted in the workshop manual. I also cleaned and checked the brake pads and calipers - all was in order. The only issue i had was a wear lip on the disc of approx 2 to 3mm on the outer and inner radiouses-this is caused by normal use ie:-the brake pads wearing the disc material as the brakes are applied. I checked how much meat was left on the disc and found again it was within tolerance so thinking that maybe the lip was the cause i carefully ground them down to the same level as the rest of the disc using my hand grinder (not recommended for peeps with a nervous disposition or shaky hands). I then carefully put everything back as the manual states in reverse order using Copper Grease in the appropriate areas.

I then stripped and checked the O/Side front - this checked out exactly as per the N/Side so i carried out the same work as above and then went for a run - S!!!t the problem was still there.

Next i proceeded to strip the O/Side rear - again eveything was in good order and as per Workshop Manual tolerances other than the wear lips on the disc which also received the same treatment as the fronts.

Finally i stripped the N/Side rear and to my relief immediately saw the cause of my brake pulsing problem - i had a faulty disc - the disc forging had a hard bit of metal embedded/cast into it (approx 10mm wide x 30mm long). The pulsing was caused by the hard metal ie the softer metal either side of it had worn down by normal use of the brake pad leaving the hard bit protruding slightly. As the brakes were applied and the wheel was turning the hard bit intermittently came into contact with the brake pad which in turn caused the pulsing.

I will upload my photos detailing this fault if someone can explain to me how to do it ??

To get the car back on the road and to see if i had sorted the problem i carefully ground the hard bit of metal down to slightly below the level of the softer part of the brake disc and put everything back and went for a run - the pulsing had gone and i have had no problems since - job done.

Moral of the story is 1) don't assume its the fronts that are at fault 2) Always check everything carefully and 3) You don't have to spend hundreds of pounds sorting it out !!!!!

I apologise for the lengthy nature of this post but maybe my experience will help others in the future.

[Steviewevie]

I will upload my photos detailing this fault if someone can explain to me how to do it ??

There's a handy guide here

[Dan_Harris]

the problem I have is nowhere that I trust has a device to measure the disc or DTI as you put it. The only place likely to is Kwik Fit and well their reputation is hardly admirable, will bite the bullet and get the front discs changed then see where I'm left after that me thinks.