Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: omega3000 on 19 April 2012, 17:32:15

Title: Brake squeal .
Post by: omega3000 on 19 April 2012, 17:32:15
When reversing and braking ie off the drive im getting a brake squeal from the rear , the whole brake system has had a overhaul including replacement pins and squeal plates ...handbrake shoes and drum were rubbed down and cleaned . Strange  ???
Title: Re: Brake squeal .
Post by: feeutfo on 19 April 2012, 18:15:50
What rear pads fitted?

Are the hand brake shoes binding a fraction?
Title: Re: Brake squeal .
Post by: holtender on 19 April 2012, 18:25:23
Did you apply any Copper Slip?
Title: Re: Brake squeal .
Post by: omega3000 on 19 April 2012, 18:34:20
What rear pads fitted?

Are the hand brake shoes binding a fraction?

Pads were ok , dont know what make they were though and shoes were adjusted to bind very slightly .

Did you apply any Copper Slip?

Copper slip applied .
Title: Re: Brake squeal .
Post by: feeutfo on 19 April 2012, 19:16:21
What rear pads fitted?

Are the hand brake shoes binding a fraction?

Pads were ok , dont know what make they were though and shoes were adjusted to bind very slightly .

Did you apply any Copper Slip?

Copper slip applied .
There ya go. Proof. Copper slip does not stop brake squeal. Ask TheBoy. He'll tell you the same. ;)

And ask Kai as well. Pads dripping in copper slip and squealing like a squadron of stuck pigs. Flying pig pun intended. ;)
Title: Re: Brake squeal .
Post by: omega3000 on 19 April 2012, 19:22:51
So ill clean off all the copper slip .
What shall i replace that with ...normal grease or that white grease stuff  :)
Title: Re: Brake squeal .
Post by: TheBoy on 19 April 2012, 21:00:08
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D
Title: Re: Brake squeal .
Post by: omega3000 on 19 April 2012, 21:27:53
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D
???

Think ill try a new set and see how it goes  :y
Title: Re: Brake squeal .
Post by: Andy B on 19 April 2012, 21:34:02
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D

No idea Jammie  :-\ :-\ ........ any clues?  ::) ::) ::)
Title: Re: Brake squeal .
Post by: dbug on 19 April 2012, 22:51:00
Copperslip rules OK  ;)
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 00:17:14
Copper slip has no place on brake systems! :)

Title: Re: Brake squeal .
Post by: Andy B on 20 April 2012, 00:32:44
Copper slip has no place on brake systems! :)


I think you're on your own with that theory.  ;) ;) ;) ;)
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 00:40:58
Yep, and your all wrong!


Although I may concede it might make a slight difference of up to a week on very mild squeal cases.

There is absolutely no doubt it makes no difference to squeal on trade club pads. Proven. The end. You know it, I know it, accept it, move on! :)
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 00:45:45
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D

You have copper slip on your pads, they squeak like buggery.
I have no copper slip on my pads, as it has no place on braking systems, and they don't squeal. Prosecution rests. ;D
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 07:44:32
Why do they squeal when braking in reverse though and not forward  ???
Title: Re: Brake squeal .
Post by: MrMoffat on 20 April 2012, 08:29:03

I had the same problem, but in my case a small stone from my drive got lodged next to the disc and pad & only came in contact when in reverse  :o  luckily I discovered the stone before any real damage occurred  :y
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 08:39:22
It only does it from cold though , once the car has been used and there is heat in the discs it wont squeal  ??? Its all functioning as it should , i can live with it but just weird how its started doing it since the new parts were fitted and went through MOT with no problem . Pads were half worn so ill fit new ones and use grease on re-fitment instead of coppa slip and see what that does  ::)
Title: Re: Brake squeal .
Post by: Andy B on 20 April 2012, 08:41:39
..... and use grease on re-fitment instead of coppa slip and see .,...

Not a good idea. Use copperslip or nothing, you dn't want melted grease over your discs & pads.  ;)
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 08:44:38
..... and use grease on re-fitment instead of coppa slip and see .,...

Not a good idea. Use copperslip or nothing, you dn't want melted grease over your discs & pads.  ;)

Well thats what i thought but in a post i read it was said that the high temp white grease was used on the back of the pads ...just a slight smear of it , ive always used coppa slip in the past  ;)
Title: Re: Brake squeal .
Post by: Andy B on 20 April 2012, 08:57:09
..... ive always used coppa slip in the past  ;)

So have most people, Chris is in the minority  ;) ;)
IMO it's more important though to put a wipe of copperslip at all metal to metal contact/slide points between the caliper & the pad.
Title: Re: Brake squeal .
Post by: Cliffo B on 20 April 2012, 09:56:28
I wholeheartedly agree with Chris :y :y
No grease of any sort
Friction material and lube are not compatable
Quality pads sat in calipers with minimum corrosion/wear is the route to go
Reverseing squeal I think can be caused by excess pad twist/displacement due to lack of support for the pad from the caliper
Unfortuneately the recent policy of useing sticky additives to winter road de-iceing treatments
Means these sticky corrosive chemicals are forced in and stay around within cast iron calipers a lot longer
I try to minimise this problem by hoseing/flooding the calipers with fresh water when I wash miggy especially when de-icing road treatment prevails
 
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 11:17:26
Is it when driving backwards?

Or when braking backwards?
Title: Re: Brake squeal .
Post by: Kevin Wood on 20 April 2012, 11:46:42
Obviously brake friction materials are normally used when the car is in forward motion. This can lead to a feathered edge appearing on the trailing edge of the pad / shoe.

Perhaps this is causing the squeal. If it gets particularly irritating, it might be worth removing the pads and filing a bevel on both edges of the pad to see if that helps.
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 12:04:44
For info, I've been slating trade club pads on here for years. The ones that come in the disc pad set. They squeal and give a very dead feel at the pedal. Or at least the ones from my dealer do.

TB, due to his crippleness, asked me to pick up a trade club disc pad set for him, and I fitted them for him. I refuse to use copper slip on brakes as you all know, no doubt, so TB applied his own copper slip where he wanted it. On the back and edges if the pad backing. All fitted job done.

Next thing, we get a thread on here. TB moaning about brake squeal and a dead pedal feel. Now TB can be a retard in certain areas. The state if his tyres seems beyond his understanding for instance, we all have our weak points. But I'm fairly sure he is capable of applying copper slip where he wants it, however fruitless an exercise that may. But if ever there was proof needed that copper slip is not a cure for brake sqeal, then that is it. Regardless of him admitting it or not.

I do agree with Andy Bedantic that the edges are a key area, and oe pads have shims that cover that area separating the pad metal from the caliper and stopping resonance. How anyone expects copper slip to last, not be forced aside by massive hydraulic pressure, survive all weathers and detergents AND stop brake sqeal and the resonance that causes it is beyond me.

But I guess just because somebody "always uses it" means that must be the cure, right? Maybe TB should rub it his spine, it will fix that as well. ;D although strawberry jam sales dept might come up with a reason why that might work better.

If you want to prove copper slip works, show me pads that squeal. Apply copper slip, and if the squeal us still gone in a fortnights time, then I "might" believe you.

Fact is, it didn't stop TB's from sqealing. Nothing said on here is ever going to change that.
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 12:06:38
Is it when driving backwards?

Or when braking backwards?
And is the squeal affected when reversing and gently applying the hand brake?
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 12:39:15
Is it when driving backwards?

Or when braking backwards?
Just squeals when reversing off the drive when the brake is applied going back . I never applied coppa slip to avoid any squealing issues as i had never had any , i just applied it more to stop corrosion of the back of the pads . Interestingly before i could replace the metal shim plate that hooks over the pins it was ok ..its just since i put the new plates in that its been doing it  ;)

Hmm thats just got me thinking now as it never had any coppa slip on them before and it never squealed so since ive put coppa slip on it been squealing  :o
Title: Re: Brake squeal .
Post by: Kevin Wood on 20 April 2012, 12:44:35
Sounds like my last set of TC pads (from a "pad plus disk" set), tbh. They squealed like mad for the first half of their life, then quietened down. TB, being "heavy on brakes", can therefore take comfort in the fact that they'll be fine next week. ;)

When those pads failed unexpectedly, they were replaced by standard Mintex pads from the local motor factor, with no copper grease used. Haven't heard a murmur from them in 10k miles.

Now, if you want to hear pads that squeal you should hear the ones currently on my Westfield. Problem is, they work so well I'm putting up with them. ::)
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 12:48:49
It brakes on a knife edge , quite supprised how good the brakes are tbh . I dont do a lot of driving/braking backwards
 ;D  so will put up with it for the mo  :)
Title: Re: Brake squeal .
Post by: Kevin Wood on 20 April 2012, 13:33:17
It brakes on a knife edge , quite supprised how good the brakes are tbh . I dont do a lot of driving/braking backwards
 ;D  so will put up with it for the mo  :)

There's yer problem. ;)

I prescribe a couple of hours of J-turn practice. :y
Title: Re: Brake squeal .
Post by: Cliffo B on 20 April 2012, 13:35:43
Back in Feb 2009 I replaced discs & pads on all 4 corners of Miggy
The rear discs are vented and at the time I remember I struggled to get these
A few months later I replaced the rear calipers
That was a long drawn out process
They are no longer made and exchange/ reserviced ones are available only
This means the integrity of the castings is very much in question and a matter of luck
With a great deal of trouble I managed to get a new (old stock) R/H one
The L/H one was an exchange reserviced one from a specialist firm which was as nearly new
This after rejecting at the dealers counter one of their S/order exchange reserviced ones
Since I did this job Miggy has had really effortless smooth positive progressive brakeing
And still is
However I think she may be now ready for some replacement pads as pedal travel has increased slightly
This after about 30,000mls so I'm not complaining :y   
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 13:38:06
It brakes on a knife edge , quite supprised how good the brakes are tbh . I dont do a lot of driving/braking backwards
 ;D  so will put up with it for the mo  :)

There's yer problem. ;)

I prescribe a couple of hours of J-turn practice. :y

Swmbo will be impressed  ;D
Title: Re: Brake squeal .
Post by: Cliffo B on 20 April 2012, 13:41:59
Ahh Kevin miggy's discs & pads are Mintex
Will of course be useing the same again :y
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 14:48:27
For info, I've been slating trade club pads on here for years. The ones that come in the disc pad set. They squeal and give a very dead feel at the pedal. Or at least the ones from my dealer do.

TB, due to his crippleness, asked me to pick up a trade club disc pad set for him, and I fitted them for him. I refuse to use copper slip on brakes as you all know, no doubt, so TB applied his own copper slip where he wanted it. On the back and edges if the pad backing. All fitted job done.

Next thing, we get a thread on here. TB moaning about brake squeal and a dead pedal feel. Now TB can be a retard in certain areas. The state if his tyres seems beyond his understanding for instance, we all have our weak points. But I'm fairly sure he is capable of applying copper slip where he wants it, however fruitless an exercise that may. But if ever there was proof needed that copper slip is not a cure for brake sqeal, then that is it. Regardless of him admitting it or not.

I do agree with Andy Bedantic that the edges are a key area, and oe pads have shims that cover that area separating the pad metal from the caliper and stopping resonance. How anyone expects copper slip to last, not be forced aside by massive hydraulic pressure, survive all weathers and detergents AND stop brake sqeal and the resonance that causes it is beyond me.

But I guess just because somebody "always uses it" means that must be the cure, right? Maybe TB should rub it his spine, it will fix that as well. ;D although strawberry jam sales dept might come up with a reason why that might work better.

If you want to prove copper slip works, show me pads that squeal. Apply copper slip, and if the squeal us still gone in a fortnights time, then I "might" believe you.

Fact is, it didn't stop TB's from sqealing. Nothing said on here is ever going to change that.

 ;D they do grind down a bit once they hit the metal .
Title: Re: Brake squeal .
Post by: TheBoy on 20 April 2012, 21:38:06
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D

You have copper slip on your pads, they squeak like buggery.
I have no copper slip on my pads, as it has no place on braking systems, and they don't squeal. Prosecution rests. ;D
The common demoninator on squealy TC pads is you ::)
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 21:42:54
I always use copper grease, never, ever had squeaky brakes before this set. Guess who fitted them ;D

You have copper slip on your pads, they squeak like buggery.
I have no copper slip on my pads, as it has no place on braking systems, and they don't squeal. Prosecution rests. ;D
The common demoninator on squealy TC pads is you ::)
That's denial, pure and simple ;D
Title: Re: Brake squeal .
Post by: TheBoy on 20 April 2012, 21:50:11
Moaning at gayboy aside, I do wonder if there is a pattern. Being serious for a while...

Never had squeals before, gayboy says every time he's used TC pads he has.  Upon questioning, he thinks all his TC pads have been ones that have been supplied with discs.

I can't, hand on my heart, say I've ever used pads from the disc and pad sets - usually other members have needed them more desperately than I have.  So this may be the first set of pads that have been supplied like that.

And guess what? Whilst they stop the car, they are lifeless, with no feedback. And squeal like a pig.


Will find out soon, I need to replace these pads soon, going by mileage - they're about 4k in now...
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 22:09:21
I have also noticed that the pad friction material shows quite heavy cracks across the surface.
TheBoy, I would suggest changing them sooner rather than later.

I have had various theory's, but never really fully accepted that there are two sorts of trade club pads available. Given Kevs experience with pad material braking off, and your heavy on brakes... I think a quick trip to the dealer is in order.
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 22:11:50
So do yours squeal in any braking direction, as mine only do it when braking to stop after reversing ...im going to wipe off all the coppa slip and re fit them then see if it makes any difference before buying new pads  :)
Title: Re: Brake squeal .
Post by: feeutfo on 20 April 2012, 22:13:02
So do yours squeal in any braking direction, as mine only do it when braking to stop after reversing ...im going to wipe off all the coppa slip and re fit them then see if it makes any difference before buying new pads  :)
Nope, not playing. ;D
Title: Re: Brake squeal .
Post by: YZ250 on 20 April 2012, 22:15:52
The disc's and pads on mine are from the TC disc and pad set and do not squeal. They have covered about six thousand miles with no issue. IIRC they have stick on shims, not the wrap around one's. I will admit that the best pads for sharpness were the one's originally fitted when the car was new. Any replacements since have given a 'hmm, this could be interesting' feel when urgently needed.  ::)

On a side note, I have never seen such a large leading/trailing edge as on TC pads. The contact face is seriously reduced by such a huge camber.  :-\
Title: Re: Brake squeal .
Post by: VXL V6 on 20 April 2012, 22:16:50
Moaning at gayboy aside, I do wonder if there is a pattern. Being serious for a while...

Never had squeals before, gayboy says every time he's used TC pads he has.  Upon questioning, he thinks all his TC pads have been ones that have been supplied with discs.

I can't, hand on my heart, say I've ever used pads from the disc and pad sets - usually other members have needed them more desperately than I have.  So this may be the first set of pads that have been supplied like that.

And guess what? Whilst they stop the car, they are lifeless, with no feedback. And squeal like a pig.


Will find out soon, I need to replace these pads soon, going by mileage - they're about 4k in now...

The set I gave you were from a Tradeclub set, not sure if they ever found their way onto either of your cars.
Title: Re: Brake squeal .
Post by: omega3000 on 20 April 2012, 22:25:38
So do yours squeal in any braking direction, as mine only do it when braking to stop after reversing ...im going to wipe off all the coppa slip and re fit them then see if it makes any difference before buying new pads  :)
Nope, not playing. ;D
>:( ;D

The wheelie bin is quite near so if no joy ill slingem  ::)
Title: Re: Brake squeal .
Post by: martin42 on 20 April 2012, 23:23:13
Ive used a £10 set of rear pads,copper greased them on the rear of pads and also where they fit at top and bottom of caliper and never squealed  :y
Title: Re: Brake squeal .
Post by: feeutfo on 21 April 2012, 07:08:59
Ive used a £10 set of rear pads,copper greased them on the rear of pads and also where they fit at top and bottom of caliper and never squealed  :y
How do you know they squealed at all? If they squealed and applied cs to stop the squeal, and keep it stopped, them you'd have something.

IME the ONLY way to stop squeal properly is fit shims on all pads.
Title: Re: Brake squeal .
Post by: TheBoy on 21 April 2012, 09:28:00
I have also noticed that the pad friction material shows quite heavy cracks across the surface.
TheBoy, I would suggest changing them sooner rather than later.

I have had various theory's, but never really fully accepted that there are two sorts of trade club pads available. Given Kevs experience with pad material braking off, and your heavy on brakes... I think a quick trip to the dealer is in order.
I've had a spare set here for a couple of weeks, as they must be getting down a bit. Just need to find time/strength to do it.
Title: Re: Brake squeal .
Post by: omega3000 on 21 April 2012, 12:42:51
To cs or not to cs that be the question  ::) not investigating just yet as swmbo had me running to the tip all morning with garden waste  ::)
Title: Re: Brake squeal .
Post by: Cliffo B on 21 April 2012, 13:13:00
For a level playing field I think  you need newish calipers :y
Title: Re: Brake squeal .
Post by: feeutfo on 21 April 2012, 16:25:43
As an example, I always remember Kai's rear brakes. Absolutely horrendous squeal. Touch the brakes and it was deafening. He drive it round to mine to fit new pads. I suggested oe as they have the rubber backing on all pads and come complete with pins shims and springs. He agreed a bought them with him to fit.

On removing the old ones that where drenched in copper slop that was poring down and dripping iff the caliper, the problem was clear. No shims, but also, the thick paint on the metal backing had cracked due to piston pressure. The weather had then got in and rust had raised the area causing the pads to rock on the piston over the raised rusted area. As the frequency of the rock increased with wheel speed, so did the squeal. Ferrodo skimping on shims.

Title: Re: Brake squeal .
Post by: TheBoy on 21 April 2012, 22:09:33
Well. Lets chuck this in the mix. I should state its early days yet, but....

Went to change the squealy MV6 pads this afternoon. Turns out I've been a good boy, and the pads are little over a 1/3rd worn. So a couple of thousand left.

As I had new pads, I nearly fitted them, but then, to for research purposes, decided to refit the part worn ones.  Cleaned up, filed a better edge on the leading edge, and refitted.

Took it for a blat, the 'bite' feels better (or did before I cooked them), and the squeal is no longer present. Feel? I think its better, but might be placebo.

 :-\

Early days, only done 12 miles. Fully expect squeal to return, as not really done anything different. But last time the squeal was there from the start  :-\
Title: Re: Brake squeal .
Post by: feeutfo on 21 April 2012, 22:25:18
They have enoooormous chamfers on them already... ??? Almost a third of the braking surface is lost because of it.  :-\

Anyway, as you say, in the name of research let's see. :)
Title: Re: Brake squeal .
Post by: TheBoy on 21 April 2012, 22:41:14
I think the standard chamfers are naff - too shallow, thus lose a lot of area. I noticed the entire chamfer was clogged with dust.  Filed on a much steeper chamfer - about 45 degrees, down as far as about 4mm from backing plate. And only on leading edge.
Title: Re: Brake squeal .
Post by: feeutfo on 21 April 2012, 22:58:53
Any cracks on the friction material surface?
Title: Re: Brake squeal .
Post by: TheBoy on 22 April 2012, 09:17:09
Any cracks on the friction material surface?
No, if there had been, after hearing of Kevin Wood's problem, they would have been binned.
Title: Re: Brake squeal .
Post by: TheBoy on 22 April 2012, 09:19:10
Thinking aloud, wonder if Kevin Wood's had been badly handled, maybe dropped or otherwise thrown about by dealer/courier/GM Warehouse, causing the brittle pads to start to fracture internally  :-\
Title: Re: Brake squeal .
Post by: feeutfo on 22 April 2012, 13:37:36
Possible I suppose, but fitting new pads, I wouldn't fit cracked friction material from new, mine where fine, yet showed minor cracks after less than 5k.

I wonder if a more even comparison between the in set pads, and on thier own pads, would be to swap them early? A more direct comparison?
Title: Re: Brake squeal .
Post by: TheBoy on 22 April 2012, 21:13:48
Possible I suppose, but fitting new pads, I wouldn't fit cracked friction material from new, mine where fine, yet showed minor cracks after less than 5k.

I wonder if a more even comparison between the in set pads, and on thier own pads, would be to swap them early? A more direct comparison?
The part number for my new pads, and part number printed on the pads you fitted match...

Wonder if in Kevin Wood's case, if any mishandling was more hairline cracks, not immediately obvious when fitting?  Its a worrying thought if its poor manufacturing.
Title: Re: Brake squeal .
Post by: TheBoy on 22 April 2012, 21:14:23
BTW, went out in it today, still no squeal :)
Title: Re: Brake squeal .
Post by: feeutfo on 22 April 2012, 21:17:08
Do you reckon dust is/was getting dragged in between the disc and pad when braking and causing the squeal?
Title: Re: Brake squeal .
Post by: dbug on 23 April 2012, 00:10:45
BTW, went out in it today, still no squeal :)

Think you may have cracked it Jaime ;)

Normal way to get rid of/reduce brake squeal is to chamfer leading edges on disks or shoes ;) ;)

Quote
Do you reckon dust is/was getting dragged in between the disc and pad when braking and causing the squeal?

Possibly Chris - more possible that as pad wears a "raised" edge builds up on leading edge inducing squeal.

Agree that Vx chamfers on pads too shallow an angle over too large an area.