Hi all,

 

I thought I’d throw this out here to knock some heads together as this problem is really frustrating me now!

 

It started off as a very mild vibration when braking at speeds at around 80mph and above but gradually got worse over a period of months. It was never “too” bad but I decided to try and rectify it before a trip to the Lake District and now it’s become “too” bad!

 

As it stands I get fairly severe vibration at all speeds down to around 20-30mph where it fizzles away. When I first take the car out, it’s nice and smooth with no feedback but after the 2nd or 3rd use of the brakes it begins to worsen and after that it’s at its worst. When I release the brake pedal, all vibration stops and it’s back to smooth sailing, no vibes are evident through the seat.

 

Here’s what has been done:

- Run out checks of both front wheel hubs

- DBA 4000 discs with around 10k miles on were turned down using an on car brake disc lathe

- Thermal paint marking on discs show no evidence of overheat

- New brake pads

- New front upper control arms after play evident in passenger arm, body side bush

- Calipers inspected for piston movement and pad movement

- Full fluid flush and bleed

- All bushes inspected (several times by servers people!) with no evidence of play

 

This little snag has me scratching my head, any ideas? I know spanking another £500 on discs is probably a good call but I just can’t see how these discs are at fault. I did another run out check on them today and they’re perfect!

 

Any advice appreciated.

I meant rear haha sorry

 

But that’s not going to help diagnose a front axle based vibration?

Have to say, it does scream disc fault. The fact all is smooth initially, then once used the wobble develops suggests the discs are distorting with some heat then returning to true when cooled down. Obviously nothing that will ever be seen by the eye. Even the mildest of distortion will cause that horrible wobble through the steering.

Throwing a cheap pair of discs at the car first sounds like a good idea before replacing them with expensive ones.

Skyline discs are inherently expensive, they are virtually the same as 350z with a small difference but that’s not beyond Mr P. That would be a cheaper option I recon for the experiment and there’s a better choice of those discs available anyway.

Skyline discs are inherently expensive, they are virtually the same as 350z with a small difference but that’s not beyond Mr P. That would be a cheaper option I recon for the experiment and there’s a better choice of those discs available anyway.

 

I would advise against going for the cheaper 350z discs as having used both them and proper GTR discs the 350z discs offer much poorer performance especially at temperature.

 

I was sceptical as they are very similar but there is a difference and after feeling it I wouldn't advise going the 350z option.

I would advise against going for the cheaper 350z discs as having used both them and proper GTR discs the 350z discs offer much poorer performance especially at temperature.

 

I was sceptical as they are very similar but there is a difference and after feeling it I wouldn't advise going the 350z option.

 

I only meant as a temporary test exchange. However I’m interested in what you say. Where both discs OEM units? Seems strange that with expectations of Brakes being so much higher these days that they’d go to the trouble to produce a cheaper inferior disc. You’d assume it’s the sale by volume that makes them cheaper, the Z33 globally sold a lot more than the R33 GTR. Also I’d assume that discs were Brembo like the caliper, brembo don’t make products specific for a car they adjust the mounting points, offsets etc to meat the customers need. For example the skyline, evo and 350z all use the same pads in the rear.

Standard brembo discs and pads with both mate.

 

I didn't expect there to be any difference after reading loads and initally they seemed the same (car had 350z discs on it when I bought it.)

 

But once I did some high speed braking there was a clear difference, just better all round.

Hi all,

 

I thought I’d throw this out here to knock some heads together as this problem is really frustrating me now!

 

It started off as a very mild vibration when braking at speeds at around 80mph and above but gradually got worse over a period of months. It was never “too” bad but I decided to try and rectify it before a trip to the Lake District and now it’s become “too” bad!

 

As it stands I get fairly severe vibration at all speeds down to around 20-30mph where it fizzles away. When I first take the car out, it’s nice and smooth with no feedback but after the 2nd or 3rd use of the brakes it begins to worsen and after that it’s at its worst. When I release the brake pedal, all vibration stops and it’s back to smooth sailing, no vibes are evident through the seat.

 

Here’s what has been done:

- Run out checks of both front wheel hubs

- DBA 4000 discs with around 10k miles on were turned down using an on car brake disc lathe

- Thermal paint marking on discs show no evidence of overheat

- New brake pads

- New front upper control arms after play evident in passenger arm, body side bush

- Calipers inspected for piston movement and pad movement

- Full fluid flush and bleed

- All bushes inspected (several times by servers people!) with no evidence of play

 

This little snag has me scratching my head, any ideas? I know spanking another £500 on discs is probably a good call but I just can’t see how these discs are at fault. I did another run out check on them today and they’re perfect!

 

Any advice appreciated.

 

You are not alone!! I have this exact same fault and put it down to breaks. They have since been replaced (3 times) and no change. I'm suspecting tension rod bushes as these could be causing the wheel to move backwards under breaking (towards the rack) and trying to push the toe in. That't my logic, ordering new ones on payday xD

Edited May 21, 20187 yr by jayjay93
spelling.....

New tension rod bushes in today - Nil fix!

New tension rod bushes in today - Nil fix!

 

Sad face

Have to say, it does scream disc fault. The fact all is smooth initially, then once used the wobble develops suggests the discs are distorting with some heat then returning to true when cooled down. Obviously nothing that will ever be seen by the eye. Even the mildest of distortion will cause that horrible wobble through the steering.

Throwing a cheap pair of discs at the car first sounds like a good idea before replacing them with expensive ones.

 

The trouble is, even the cheapo discs on eBay from MTEC and EBC etc are all between £250-300! The DBA T3 discs are around £350 and then up to £500+ when you get to brands like stoptech. I’m currently weighing up my options but the cheapo discs for troubleshooting aren’t in that list as it just seems false economy and if I’m going to spend £500+ on them I think I’d rather sell my Brembos and buy an Akebono kit using OEM 355mm 370z discs - the kit costs around £1100 from CZP.

For anyone wondering, once the brakes are hot this vibration is violent, the dials in front turn into a blur and slowing the car feels dangerous! It’s only been this bad since I had the discs skimmed!

Do you want to borrow some disks? haha

The trouble is, even the cheapo discs on eBay from MTEC and EBC etc are all between £250-300! The DBA T3 discs are around £350 and then up to £500+ when you get to brands like stoptech. I’m currently weighing up my options but the cheapo discs for troubleshooting aren’t in that list as it just seems false economy and if I’m going to spend £500+ on them I think I’d rather sell my Brembos and buy an Akebono kit using OEM 355mm 370z discs - the kit costs around £1100 from CZP.

 

The current discs you have can’t have many miles on them, they have only seen road use as far as I’m aware? Seems a bit naff that a £500 pair of discs have failed like this....

The current discs you have can’t have many miles on them, they have only seen road use as far as I’m aware? Seems a bit naff that a £500 pair of discs have failed like this....

 

That’s correct. The heat markers on the lips also suggest that the discs haven’t overheated (printed strips that change colour when subjected to certain temperatures). Looking at my invoices I paid just over £400 for these discs 5 years ago, they have covered around 7-10k miles and have had an easy life relative to the pounding they are “capable” of.

I think I’d rather sell my Brembos and buy an Akebono kit using OEM 355mm 370z discs - the kit costs around £1100 from CZP.

 

Akebono brakes are very heavy (if that bothers you). Why not consider the Ksport? They are available in the UK, cheaper and lighter.

 

https://www.dcperformance.co.uk/cheap/649906/nissan/k-sport-front-big-brake-kit/ni12-356x32.html

That’s correct. The heat markers on the lips also suggest that the discs haven’t overheated (printed strips that change colour when subjected to certain temperatures). Looking at my invoices I paid just over £400 for these discs 5 years ago, they have covered around 7-10k miles and have had an easy life relative to the pounding they are “capable” of.

 

It would be worth a stern email. I doubt you will get far esp seeing as they have now been “altered by a third party”. Plus whilst this is the most probable cause it’s not concrete, so you could be barking at the wrong people. There’s no real cheap check answer here is there.

Sorry if this has been suggested, it all got a bit too technical for me a long time ago, but could you not pop another 300s discs and calipers on your car for a test. For a man of your skills it wouldn’t take too long would it? Your more than welcome to use my car and pull my discs and calipers off, they’re standards calipers and 355 discs on a spacer.

Akebono brakes are very heavy (if that bothers you). Why not consider the Ksport? They are available in the UK, cheaper and lighter.

 

https://www.dcperformance.co.uk/cheap/649906/nissan/k-sport-front-big-brake-kit/ni12-356x32.html

I’ve never been a fan of these K-Sport or D2 type calipers for some reason, I always get the vibe that they have been designed more as a fashion statement then a full R&D backed setup. There’s probably some brand snobbery in there somewhere too! I have held a 370z akebono caliper and they are quite heavy, I hadn’t really considered that factor, food for thought.

 

It would be worth a stern email. I doubt you will get far esp seeing as they have now been “altered by a third party”. Plus whilst this is the most probable cause it’s not concrete, so you could be barking at the wrong people. There’s no real cheap check answer here is there.

Yes you’re right it’s worth giving them some feedback and to highlight my disappointment with the outcome but as you say, I’ll cross that bridge when it’s concrete.

 

Also, I’m sure they get reports of this type of defect on a regular basis where there is no defect in the disc. Uneven pad deposits on the discs where sufficient cool down periods haven’t been adhered to are the primary cause of this symptom so it would be difficult to filter out the genuine reports. I will do so though, explaining that an attempt to re-bed the pad material on the discs was carried out on several occasions to no avail and, more importantly, even after having them turned down to a perfect finish, the first braking action before the new pads have even bedded in proved that the defect remained.

 

Sorry if this has been suggested, it all got a bit too technical for me a long time ago, but could you not pop another 300s discs and calipers on your car for a test. For a man of your skills it wouldn’t take too long would it? Your more than welcome to use my car and pull my discs and calipers off, they’re standards calipers and 355 discs on a spacer.

Thanks for the kind offer matey, but I really wouldn’t expect anyone to “break” into the hydraulics of the braking system on someone else’s car unnecessarily, just in case it caused issues of its own. Imagine shearing a brake line or a bleed nipple and being in a pickle yourself! Not only that, the car is unuseable in its current state really, it feels dangerous at motorway speeds or after a few roundabouts and also is doing the car no good from the juddering!

Get yourself on one of the Skyline clubs and see what you can blag. I bet somebody will lend you some spare, second hand etc discs just to drive around a bit and see what happens. I think really that’s the best option.

Joel...you seem to have covered everything that could be the cause...so perhaps revisiting some of them may throw some new light on the situation?....like removing the disc and ensuring the contact points on disc and hub are perfectly clean....and perhaps try another set of brake pads...you could have been unlucky enough to have got a duff set....I have had that myself...with brembo pads!

I’ve never been a fan of these K-Sport or D2 type calipers for some reason, I always get the vibe that they have been designed more as a fashion statement then a full R&D backed setup.

 

A bit beyond a fashion statment - take at their corporate website: http://www.k-sportracing.com/aboutus.htm

and their videos for their R&D, manufacturing and QC: http://www.k-sportracing.com/video.htm

 

Their BBKs are used extensively in competitive events all over the world with success.

 

When it comes to replacing parts when worn - discs and pads can be replaced with AP Racing, Ferodo, Mintex, Pagid etc.

 

Sure they are a cheaper option than say AP Racing and Brembo GT BBK's but they do the job nonetheless.

Get yourself on one of the Skyline clubs and see what you can blag. I bet somebody will lend you some spare, second hand etc discs just to drive around a bit and see what happens. I think really that’s the best option.

I’ve been a member of GTROC for many years now and it’s not like this place, it’s not friendly! [emoji1]

 

Joel...you seem to have covered everything that could be the cause...so perhaps revisiting some of them may throw some new light on the situation?....like removing the disc and ensuring the contact points on disc and hub are perfectly clean....and perhaps try another set of brake pads...you could have been unlucky enough to have got a duff set....I have had that myself...with brembo pads!

I’m on my 3rd way round now Gary! [emoji1]

I’ve personally removed the discs and cleaned the hub (which is remarkably clean) twice and the shop that lathed my discs also did it when they were doing run out checks etc.

I struggle to work out how the pads could cause such a violent issue but I did replace them anyway. When you consider that it started doing it with my well bedded and evenly worn pads and it’s still doing it with a new set, paired with the nature of the defect m, I’m satisfied that the defect has nothing to do with the pads or the caliper.

 

In fact, yesterday when I was testing the tension rods, once the discs were really hot and slowing down to 10mph with very light brake pressure, I could feel (and hear) what felt like the drivers front disc grabbing every rotation and slightly pulling on the wheel at the same time.

 

A bit beyond a fashion statment - take at their corporate website: http://www.k-sportracing.com/aboutus.htm

and their videos for their R&D, manufacturing and QC: http://www.k-sportracing.com/video.htm

 

Their BBKs are used extensively in competitive events all over the world with success.

 

When it comes to replacing parts when worn - discs and pads can be replaced with AP Racing, Ferodo, Mintex, Pagid etc.

 

Sure they are a cheaper option than say AP Racing and Brembo GT BBK's but they do the job nonetheless.

I’ve never really taken them seriously but on closer inspection they’re actually worth taking seriously. For a lightweight, forged monoblock caliper setup with 2 piece discs at those prices, I’m struggling to find any negatives. They seem to review very well.

I have been running K Sports Joel, and have been impressed with them so far.

Pretty sure Mr Morgan’s machine had Ksports as well.

cementite?

 

http://trackdayzone.com/index.php/how-to-s-main-menu/hpde-how-to-s/114-the-final-word-on-brake-vibration-and-warped-rotors