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Discussion Starter #1
Hi everyone,

I'm hoping that you'll be able to share your wisdom and help me out.

I recently (just over 1k miles ago) had some AP Racing J Hook discs and Ferodo DS2500 pads fitter all round and bedded in by Middlehurst.

I'm getting a constant judder through the steering wheel and small pulsations through the brake pedal. I've tried some hard stops to see if it was pad deposits but no difference.

Middlehurst had the car for 3 days and said they'd fixed it but within 5 miles it was back again. It's going back in tomorrow but they don't understand what's wrong. It's doing my wick in that they can't identify and fix the problem. This is on top of them mis-quoting the brakes, then fitting the grooved rears instant of J hooks, then telling me that rear J hooks didn't exist. Eventually they fitted the correct rears.

I've taken some pics of the discs - the only thing I can see on the fronts is an outer ring which is a different colour. Could it be that the pads aren't applying properly or is it something else?

Cheers,
Richard
 

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you have a bad disc, you can put a dial gauge on the face of each disc and rotate them individually to see which one has the run out or if its really bad you will be able to tell just by jacking the car up and rotating the wheel and at a certain point it will catch on the pad.
 

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Discussion Starter #3
you have a bad disc, you can put a dial gauge on the face of each disc and rotate them individually to see which one has the run out or if its really bad you will be able to tell just by jacking the car up and rotating the wheel and at a certain point it will catch on the pad.
I asked Middlehurst about this. They said that they measured the runout and they were fine. But something isn't right as the problem persists.
 

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Make sure you havent thrown a wheel weight as well.

Have you done a lot of spirited fast road driving? When I upgraded on my 370z to DBA rotas with DS2500 I managed to throw the rotas out of tolerance in less than 500 miles due to the heat they were generating (the DBA's have heat paint on the side to allow you to see how hot they get)

Another question would be after a spirited drive and once you've stopped the car whats your procedure for switching off. Do you find that the brakes bind when the car has been sitting?

I was told by a gentleman that is on his 5th GT-R that if you leave the car running for 45 seconds after stopping the pistons retract slightly stopping this binding from happening. I now do this and can say that I have not suffered with binding brakes since.
 

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Discussion Starter #5 (Edited)
Make sure you havent thrown a wheel weight as well.

Have you done a lot of spirited fast road driving? When I upgraded on my 370z to DBA rotas with DS2500 I managed to throw the rotas out of tolerance in less than 500 miles due to the heat they were generating (the DBA's have heat paint on the side to allow you to see how hot they get)

Another question would be after a spirited drive and once you've stopped the car whats your procedure for switching off. Do you find that the brakes bind when the car has been sitting?

I was told by a gentleman that is on his 5th GT-R that if you leave the car running for 45 seconds after stopping the pistons retract slightly stopping this binding from happening. I now do this and can say that I have not suffered with binding brakes since.
I tend to leave it for 30 seconds as per the manual before turning off and I don't sit with my foot on brake at lights - always go into neutral and put the handbrake on and no binding at all.

Not really - I'm quite easy on the brakes most of the time and haven't done any heavy stopping (other than to try and clear pad deposits). I know the GTR is a heavier car but I did track days in my RB320 STI with no problems on Brembos and my EP3 Civic Type R had a caliper that welded itself on and that didn't cause any DTV so I'm totally stumped.

I don't think I've lost a weight but I'll ask them to check. I would have thought that this would have caused judder all the time though?
 

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I tend to leave it for 30 seconds as per the manual before turning off and I don't sit with my foot on brake at lights - always go into neutral and put the handbrake on and no binding at all.

I don't think I've lost a weight but I'll ask them to check. I would have thought that this would have caused judder all the time though?
I've only had the car a month or so, and never read the manual :chuckle:

I would agree to the weight but I seem to remember some slight pulsing in mine which has now vanished after the wheels were refurbed (inc. wheel balance )

What did they do for it to disappear for that short time?
 

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Discussion Starter #7
I've only had the car a month or so, and never read the manual :chuckle:

I would agree to the weight but I seem to remember some slight pulsing in mine which has now vanished after the wheels were refurbed (inc. wheel balance )

What did they do for it to disappear for that short time?
Haha - the manual is fairly large.

The short time was all of 5 minutes. They said they cleaned everything up on the brakes and hubs and measure the run out. Personally I don't think it actually did go away.
 

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I'm a little stumped here myself.

Do you remember when the wobble started, or do you think its always been there?

Is it getting worse or staying the same?

Do you get any wobble at any speed not touching the brake?

When it goes back ask if the pads are wearing correctly, both sides of the disc.

Other than that you may need to clean up the face of the discs.
 

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Discussion Starter #9
I'm a little stumped here myself.

Do you remember when the wobble started, or do you think its always been there?

Is it getting worse or staying the same?

Do you get any wobble at any speed not touching the brake?

When it goes back ask if the pads are wearing correctly, both sides of the disc.

Other than that you may need to clean up the face of the discs.
They cleaned the faces of the discs when it was in last, they said.

No wobble at speed - only when braking. It started just over a couple of weeks ago. When they were initially fitted they were fine. It did have DTV when I bought it hence the change of discs which makes me think something is out somewhere on the caliper.
 

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If the symptoms go when the discs are cleaned I would suggest it must be something to do with the J-Hooks collecting brake material......mine did the same but with a different pad. I ended up changing discs.
 

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Discussion Starter #11
If the symptoms go when the discs are cleaned I would suggest it must be something to do with the J-Hooks collecting brake material......mine did the same but with a different pad. I ended up changing discs.
The thing is it didn't go. It was fine for 5 miles until I got on the dual carriageway and then came back. Personally I think it was still there but the speeds are so low from the dealer to the dual carriageway that it couldn't manifest itself.

What pad were you using at the time and what discs did you change to?
 

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Discussion Starter #15
take a read of the below x2 threads, might help
https://www.gtr.co.uk/forum/492193-slight-vibration-under-braking-2.html#post5118793
https://www.gtr.co.uk/forum/371858-borg-beck-bbp2436-brake-pads-where-buy-3.html#post4155513

Just throwing this in, only time i ever got brake judder is when i got borg and beck pads, and its was the pads itself causing it.. swapped to ds2500 as was ok... i can see you are using these, so maybe a pad fitment/fault/deposits?
Thanks for the links - I'd had a look through them earlier to try to identify the problem. There was also a thread where someone got a wheel refurbished and Nissan said that this warped the hub although I really struggle to see how you can warp a hub.

The weird thing is before the brakes were cleaned there was no pulsation in the pedal - only the wheel. Since then it's in both. Annoying!
 

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Maybe run the car over to AC Speedtech as they're just down the road (in Warrington) from Middlehurst. They can probably take there car out for a spin and let you know if there is a problem / what it is.

Does the vibration only happen during gentle braking or also during harder braking?
 

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Discussion Starter #19
Maybe run the car over to AC Speedtech as they're just down the road (in Warrington) from Middlehurst. They can probably take there car out for a spin and let you know if there is a problem / what it is.

Does the vibration only happen during gentle braking or also during harder braking?
That's my plan if they're unable to fix it or if the dealer comes back saying it's not the parts or the fitment as I'd like a 2nd opinion. I did contact them asking if I could bring it in and they were helpful. I know a few guys on here use them so they must be good.

I also contacted Ferodo who said they'd support the dealer and AP Racing who were a bit stumped. They thought that old or incorrect pads and/or discs were fitted but I've checked the part numbers and they're all correct. They did feel that the outer ring of rust around the edge of the disc indicated that the pad wasn't applying to the disc uniformly and could be the problem.

I can feel the pedal pulse on light braking then on moderate the pedal and the wheel. Hard braking it either disappears or is very minimal.
 

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I am pretty sure middlehursts have the knowhow to resolve the issues, they used to race gtr***8217;s so they should have seen most things and found solutions.
 
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