[Ess]

Hello,

I've recently noticed that when breaking hard and only at motorway speeds, I get a subtle but unmistakable vibration through the steering wheel. If iI brake hard at lower speeds, say from 50mph, I can't feel anything. It's only at higher speeds and only when braking hard, gentle braking doesn't cause it, even at higher speeds. Other that the vibration, everything seems normal, the car stops as expected, etc.

I noticed this yesterday for the first time. Any thoughts are greatly appreciated!

[old grey steve]

Difficult one Seb to pin down but there are a few communist issues

One thing you can do as yours is an Auto Seb is while rolling(slow speed)tap the brake pedal, if you feel a jolt as such(difficult to describe) chances are it may well be your lower tension struts, which as you know a few of us have replaced with M3 items. I know you said you can't feel a vibration at lower speeds only higher but it's fair to say that if you haven't had any suspension work done on the car for some time, these units eventually start to play up lose their rigidity and show their hand. The second set of lower arms on the vehicle can also promote these sort of things.

The above may not be the solution at all but it's common and can lead to vibrations.

I know this is kinda difficult to describe but I need to ask how the vibration comes about. If you were to watch the steering wheel for instance does it shake when you brake, by this I mean up'n'down? Check this video out as it kind of shows the shaking sensation I talking about

If so it may well be a rotational heat related issue therefore are we seeing issues re say a seized calliper, are we having issues re corrosion on the discs, corrupted sliders? Any smells as well?

Have a look at your discs Seb(when cold see if you can feel a lip on the disc, also are the discs scored(groved)and are they discoloured?

Only real cast iron way to know us to ideally have the car in front of us

[Ess]

Thanks for all the advice as always Steve. I've got a 150 mile drive home tomorrow so I'll try to reproduce it and to describe it for you better tomorrow. The steering vibration feels like a left to right vibration, as if the wheel is turning a tiny bit to the left then to the right, though very fast and over and over. In fact it seems very similar to what is described at the start of the video which you posted.

I'll have a look at the disks and check for the issues you described. Last time I cleaned the car they looked normal and I didn't notice any smells when it was happening yesterday. I've got your words of warning about painting of the calipers and seized calipers ringing in my head now...

Thanks again for your advice. I'll feedback when I've replicated it again. I should probably pop over to see you for a check up and my rear light coding, so we can add this one to the list!

[old grey steve]

Originally Posted by Ess

Thanks for all the advice as always Steve. I've got a 150 mile drive home tomorrow so I'll try to reproduce it and to describe it for you better tomorrow. The steering vibration feels like a left to right vibration, as if the wheel is turning a tiny bit to the left then to the right, though very fast and over and over. In fact it seems very similar to what is described at the start of the video which you posted.

I'll have a look at the disks and check for the issues you described. Last time I cleaned the car they looked normal and I didn't notice any smells when it was happening yesterday. I've got your words of warning about painting of the calipers and seized calipers ringing in my head now...

Thanks again for your advice. I'll feedback when I've replicated it again. I should probably pop over to see you for a check up and my rear light coding, so we can add this one to the list!

if the vibration is a"left to right"type of vibration if your describing what I'm thinking I'd be looking at sliders / callipers as its a binding related issue normally,check on those nice wheels for exessive brake dust build up compared with what you are used to seeing on your wheels, but all you can do I suppose it monitor the situation.

[Ess]

Originally Posted by old grey steve

if the vibration is a"left to right"type of vibration if your describing what I'm thinking I'd be looking at sliders / callipers as its a binding related issue normally,check on those nice wheels for exessive brake dust build up compared with what you are used to seeing on your wheels, but all you can do I suppose it monitor the situation.

Thanks Steve, I'll have a look and will feed back. If it is what you're thinking, is it repairable?

[old grey steve]

Originally Posted by Ess

Thanks Steve, I'll have a look and will feed back. If it is what you're thinking, is it repairable?

Everythings repairable Seb, just depends on the issue itself, based on what you've said thinking steers my mind to the suggested things stated.

To be fair though could be a number of other things creating the issue your having

But on something like this once anaylised you'll have the answer you need

[Ess]

Originally Posted by old grey steve

Everythings repairable Seb, just depends on the issue itself, based on what you've said thinking steers my mind to the suggested things stated.

To be fair though could be a number of other things creating the issue your having

But on something like this once anaylised you'll have the answer you need

Great, thank you Steve. Don't know what I'd do without you!!

[Aragorn30d]

Mine does something similar, however mine sorta comes and goes, sometimes its very noticeable other times theres either nothing at all or only a mild shake. Sometimes it does it under light braking and gets better if you brake harder, other times it gets worse the more you press. Its rarely noticeable at lower speeds, usually motorway/dual carridgeway type driving.

To me it feels like "warped" brake disks, but clearly if it were that, it wouldnt come and go.

I also get a "wheel balancing" type vibration that comes and goes too, perhaps related, but i'm going to get the wheels checked for balance and straightness first and at least rule that out.

[jimpom23]

Mine did this and I took it to my local Kwik Fit (I know, but just wanted it on their machine) who do a brake test and showed me their machine readout that suggested the disc was warped - despite this I was convinced it was the control arm bushes after reading on here about symptoms but having needed to do my brakes anyway - once I had done the issue disappeared...

[mjn77]

Sounds like uneven pad deposits on the brake discs.

[Aragorn30d]

yeh thats the usual cause, and is where i'll be looking after i've sorted the wheel balancing issues.

My rear disks are in need of replacement anyway, so i'll probably end up doing all four.

[old grey steve]

Originally Posted by mjn77

Sounds like uneven pad deposits on the brake discs.

This is sometimes where deposits carry through to the sliders they get dirty then all kinds of issues takes place sometimes intermittently if there's dirt with the heat and all that

[Ess]

Okay so I followed Steve's advice on my long drive home yesterday. Findings are as follows:

> I checked the discs when cold and as far as I can tell they look absolutely normal. No discoloration, and I couldn't feel anything but smooth metal - no lips, etc. (at least that I could notice).

> I tried the low speed rolling brake tap and honestly couldn't feel anything at all out of the ordinary.

> I looked for excessive brake dust and normally I wouldn't have noticed anything, but on closer inspection I noticed that the driver side front wheel seems unusually dusty, really dark grey with a thick layer of dust. I would have put this down to the long drive, except that it is noticeably more dusty than the passenger side.

>This definitely only happens when braking, and at that braking fairly hard, and at speeds over 60mph. Light braking doesn't cause it, and hard braking at slow speeds doesn't cause it either.

I'm no expert but it doesn't sound like an alignment issue to me. Could a missing wheel weight on the back wheel cause this? I jet washed one off a few weeks ago by accident of course, and taped it back but it may have fallen off again.

Thanks again for everyone's help!
Not sure what to do next other than check the wheel weight

[old grey steve]

Originally Posted by Ess

Okay so I followed Steve's advice on my long drive home yesterday. Findings are as follows:

> I checked the discs when cold and as far as I can tell they look absolutely normal. No discoloration, and I couldn't feel anything but smooth metal - no lips, etc. (at least that I could notice).

> I tried the low speed rolling brake tap and honestly couldn't feel anything at all out of the ordinary.

> I looked for excessive brake dust and normally I wouldn't have noticed anything, but on closer inspection I noticed that the driver side front wheel seems unusually dusty, really dark grey with a thick layer of dust. I would have put this down to the long drive, except that it is noticeably more dusty than the passenger side.

>This definitely only happens when braking, and at that braking fairly hard, and at speeds over 60mph. Light braking doesn't cause it, and hard braking at slow speeds doesn't cause it either.

I'm no expert but it doesn't sound like an alignment issue to me. Could a missing wheel weight on the back wheel cause this? I jet washed one off a few weeks ago by accident of course, and taped it back but it may have fallen off again.

Thanks again for everyone's help!
Not sure what to do next other than check the wheel weight

You've got to start somewhere and if there's a higher concentration of brake dust on the offisde front wheel when that's where the investigation needs to start. If the problem manifests itself through pure high speed braking that might be the effect your feeling but chances are the effects are happening at perhaps slightly lower speeds but at this time your not as yet feeling the issue through say the steering wheel or floor pan but sometimes this can be the start of the problem and over time it will start to intervine at lower speeds and be more consistant.

At higher speeds don't for get heat increases metal expands and when you brake you create more heat through the forces of friction. So you'd have to ask have you got a partially binding calliper? possible I'm sure, have you got something as simple as dirt in the slider assembly? this is again very possible.

Best way foreard would be to see if you've got any issues re the off side wheel. You could do something nice and basic re checking and see if when freewheeling the nearside wheel has the same amount of movement as the offside, if the offisde wheel has some resistance then this is your starter for 10. Sometimes a strip down, and a througher clean of the brake assembly an a good inspection of the cars pads will help reveal issue(unevenily worn pads for instance tell there own story) if you had a friendly MOT centre they could assist re checking brake imbalance something we do to cut to the chase in cases like this as an abnormal balance would clearly indicate an issue.

[Ess]

Originally Posted by old grey steve

You've got to start somewhere and if there's a higher concentration of brake dust on the offisde front wheel when that's where the investigation needs to start. If the problem manifests itself through pure high speed braking that might be the effect your feeling but chances are the effects are happening at perhaps slightly lower speeds but at this time your not as yet feeling the issue through say the steering wheel or floor pan but sometimes this can be the start of the problem and over time it will start to intervine at lower speeds and be more consistant.

At higher speeds don't for get heat increases metal expands and when you brake you create more heat through the forces of friction. So you'd have to ask have you got a partially binding calliper? possible I'm sure, have you got something as simple as dirt in the slider assembly? this is again very possible.

Best way foreard would be to see if you've got any issues re the off side wheel. You could do something nice and basic re checking and see if when freewheeling the nearside wheel has the same amount of movement as the offside, if the offisde wheel has some resistance then this is your starter for 10. Sometimes a strip down, and a througher clean of the brake assembly an a good inspection of the cars pads will help reveal issue(unevenily worn pads for instance tell there own story) if you had a friendly MOT centre they could assist re checking brake imbalance something we do to cut to the chase in cases like this as an abnormal balance would clearly indicate an issue.

Thanks for the advice as always Steve. Sounds like I just need to book her in with you guys and let you work your magic. I'll contact you through your usual channel for a booking, I'm just worried I don't have a free Saturday morning for a while...

[Aragorn30d]

It could equally be the nearside caliper is sticking OFF rather than on.

Especially if theres no abnormal heat build up on the offside that would suggest its sticking on.

As above though, stripping it all down and cleaning everything, regreaseing the pads and sliders and making sure its all free should be the first step.

[Ess]

Originally Posted by Aragorn30d

It could equally be the nearside caliper is sticking OFF rather than on.

Especially if theres no abnormal heat build up on the offside that would suggest its sticking on.

As above though, stripping it all down and cleaning everything, regreaseing the pads and sliders and making sure its all free should be the first step.

Thanks Aragorn30d, appreciate the help. I'm all booked in to go and see Steve to sort it

[Alex e92]

This is an interesting one, I'd really like to know how you get on with it. I have posted previously about an almost identical issue which is still unresolved. Mine wobble was originally discovered on a track day and I have since had front discs skimmed and runout tested, new front pads, new rear pads and discs and also front control arms pollybushed. The wobble has cured itself at normal road speeds but is still apparent when the brakes get very hot from higher speeds.

[Phil325i]

FWIW I have a similar issue which two changes of front discs/pads have failed to cure. Wheel/tyre swap side to side made no difference and hubs are quiet and spinning freely. So the next step is a new n/s/f caliper (which is where the noise/tremor is coming from). Will let you know the outcome.

[Ess]

Originally Posted by Alex e92

This is an interesting one, I'd really like to know how you get on with it. I have posted previously about an almost identical issue which is still unresolved. Mine wobble was originally discovered on a track day and I have since had front discs skimmed and runout tested, new front pads, new rear pads and discs and also front control arms pollybushed. The wobble has cured itself at normal road speeds but is still apparent when the brakes get very hot from higher speeds.

Originally Posted by Phil325i

FWIW I have a similar issue which two changes of front discs/pads have failed to cure. Wheel/tyre swap side to side made no difference and hubs are quiet and spinning freely. So the next step is a new n/s/f caliper (which is where the noise/tremor is coming from). Will let you know the outcome.

Bit concerning guys... Would love to hear the outcome Phil.

I'm going to see Steve next Saturday so I hope his guys will be able to crack it - hopefully with minimal damage to Mr. Wallet! I will of course report back.

[Phil325i]

OK latest update. New caliper fitted today...no improvement!

Virtually only thing left is a new hub bearing (at great expense). Being fitted Monday - will let you know the outcome.

[Ess]

Originally Posted by Phil325i

OK latest update. New caliper fitted today...no improvement!

Virtually only thing left is a new hub bearing (at great expense). Being fitted Monday - will let you know the outcome.

Goodness, that's not good and sounds expensive. I'm sorry to hear that.
Thanks for the update, keep us posted!