Vibration when braking

Grit Valve said:

At slower speeds steering ball joints can judder to with movment 50 to 35 is only seconds appart we will see

Click to expand...

damlimey said:

Well this is all very interesting... I must say categorically that after the refit of new discs and fully aware of how to run them in I did not drive it like I had stolen it.

I've learned a lot about my P38 on this forum from guys like you for which I am very grateful but I am not so much of a #### that I don't know how to bed in a new set of brakes.

To be fair, the possibility that it is a warped disc still makes sense but if that is what it is, then I must be buying discs made out of chocolate.

I've been through everything looking for wear and excessive play but it's all good, though I will check the sliders. The vibration is through the chassis and not directly through the steering.

I'm glad I'm not the only one having this problem and I'll keep this forum posted if a solution is found before I turn a gun on myself.

I'm going to see if I can use a process of elimination to get to the bottom of this taking on board all that your collective contributions have suggested and see what happens...

If it's a warped disc, I'll eat it. It's made of chocolate after all!

Click to expand...

damlimey said:

Well this is all very interesting... I must say categorically that after the refit of new discs and fully aware of how to run them in I did not drive it like I had stolen it.

I've learned a lot about my P38 on this forum from guys like you for which I am very grateful but I am not so much of a #### that I don't know how to bed in a new set of brakes.

To be fair, the possibility that it is a warped disc still makes sense but if that is what it is, then I must be buying discs made out of chocolate.

I've been through everything looking for wear and excessive play but it's all good, though I will check the sliders. The vibration is through the chassis and not directly through the steering.

I'm glad I'm not the only one having this problem and I'll keep this forum posted if a solution is found before I turn a gun on myself.

I'm going to see if I can use a process of elimination to get to the bottom of this taking on board all that your collective contributions have suggested and see what happens...

If it's a warped disc, I'll eat it. It's made of chocolate after all!

Click to expand...

wammers said:

Seeing as you are so knowledgeable about brakes and such one would wonder why you are asking a question on here. The symptoms you describe are typical of a warped rear disc thought you would have known that.

Click to expand...

wammers said:

Seeing as you are so knowledgeable about brakes and such one would wonder why you are asking a question on here. The symptoms you describe are typical of a warped rear disc thought you would have known that.

Click to expand...

damlimey said:

Thor1950; thanks for that suggestion it's really helpful, the new discs only have about 4000 miles on them so any distortion should be easy to measure, I've seen dial indicators on ebay...

Wammers, I'm asking questions because I want to have a thorough understanding of what the alternatives to a warp there might be underlying my problem and where would be a better forum than here where people like you with a wealth of experience to ask such questions?

While it may be a warp, a conclusion that most people jump to, I'm the one who has to pay for the fix and I'm the one who knows that I didn't over brake during the first 250 miles of having the new discs and I'm the one who had the sinking feeling when the vibration was still there immediately after the new, expensive, vented discs were fitted all round.

Incidentally, the new discs were fitted because somebody on here said "it's a warped disc" and four new sets of discs and pads later I still have the problem.

Click to expand...

jamesmartin said:

are you sure its a brake issue ?warped discs are fairly evident through the pedal ,seized vicsous coupling can give odd feel etc

Click to expand...

wammers said:

Think there would be other issues if VC was seized James. But it's worth a look i suppose. If warp is slight you won't get a lot if any feedback through the modulator.

Click to expand...

damlimey said:

Parisien; I shall be putting Lindt chocolate disc brakes in the stockings for Christmas, what a great idea.

Wammers; okay, it’s time to come clean… When this problem first occurred, it was suggested that I had a warped disc. I thought “why bugger about? Just replace everything, pads and discs all around”. So that’s what I did, using standard OEM parts.

The fault remained.

It was suggested here that I had been too heavy bedding the brakes in and that I had warped a disc by sitting on the brakes after a long, slow reduction in speed or just being too heavy footed. So I said “I’ve been a good boy I ‘ave, I took it really easy!”

But it was suggested that the market is flooded with cheap, recycled inferior brake discs and that I should get better quality discs…

So I bought at some extra cost “the drilled and slotted crap” from Terrafirma (vented & slotted at the front, slotted at the rear) and replaced once again all discs and pads. So when I drove away to the shops to buy the baked beans that was all I could afford to dine on for the rest of the month, imagine my surprise, when braking GENTLY towards the roundabout outside of Tesco’s, the return of the very vibration I had thought would be a thing of the past.


So I say again. Unless these discs are made of fudge or toffee or indeed chocolate, there might be another explanation!


Jamesmartin; thanks for reminding me. I don’t get any feedback through the brake pedal. Also, using the (auto) gears to decelerate doesn't produce the vibrations.
Comments?

Click to expand...