Why do brakes squeal ?

[BongoBongo123]

I was wondering what causes it. (sounds like the fronts to me) I had disks and pads done about a year ago and they have been a squealing a bit
since about 3 months in after having them done and ever since till now when lightly toed, the more they grab the
less they squeel. I notice it when stuck in traffic and when I am feathering them.

They were good quality parts. (ADL Blueprint disks and ADL front pads and Delphi pads on the rear)

I know about that copperease stuff. Is brake squeal more common these days cause of materials ?

Anything I can do easily or just get the garage to check them over. They seem to work fine just squeal when feathered
but are more annoying than anything. There was no noise before they were done, so it seems to relate to the new disks/pads
and not the components that were not changed.

[teenmal]

Sound like rouge pads, you could try removing them a giving them a wee dress up and check for hard shiny bits.

Take care.

[BongoBongo123]

Thanks, MOT not far off, I might ask the local garage who did them, to take a gander, they run the Bongo round to another garage that has MOT facility. (Tiny back street garage who does the basic bits and bobs that are not overly "Bongo-ey")

[ade33]

Chap next door to us runs a very nice Range Rover on a 12 plate. The brakes 'were done' before he bought it, but they've been squealing and for a posh vehicle it's just not cricket so, being handy with the spanners, he goes in...

He showed me a removed brake pad last weekend, it was about 1/3 worn.

Buried, completely intact, in the pad material and slowing being revealed as the pad wore down, was what we reckoned to be a M12 plain nut.

#truestory

[BongoBongo123]

That's nuts.

Seriously though the nut must have fallen into the pad mould or whatever they make them in during manufacture.

I doubt it did his disk much cop either. I may have a visual check through a hole in the wheel to
see if I see any scoring.

[Rup328]

I believe brake squeal is caused by the pads vibrating in the calipers as they contact the disks, and it can be eliminated by cleaning the rear of the pads and putting a thin coating of copper grease on the metal backing before replacing into the caliper.

Most repair shops seem to use minimal amounts of copper grease (or none at all), so well worth checking youself.

[BongoBongo123]

Thanks Rup, I thought that was 100pct standard to put the copperease on, you mean these days garages are hit and miss with bothering with that ? It's only £7.00 for a 500g tub.

I did my brakes once on a car it went ok, friend gave direction.. a little tricky but doable. The Bongo is a very heavy vehicle and I would not
feel as comfortable doing them with all that weight up and I have no good place to do them.

I think I will ask them to take a look, gets on your nerves hearing them.

[BongoBongo123]

Slightly interesting find today. Had a look at disks, driver side wear uniform with the normal gentle
circular arabsions all looking equal. Passenger side had a very, very slight scoring.. must be to the order of 0.2mm
mm at a guess, it just catches the light differently.

No where near 1mm deep anyway. But it does catch the sun more than the rest of the disk surface, so I have it booked in for Friday morning.
As you mentioned could have something stuck in or under the pad or just needs smearing with copper ease. Thanks for the advice !

It may or may not be the cause but is something to start with looking at.

[BongoBongo123]

Well I am peed off, paid £50.00 for nothing. Bloke said he cleaned everything and it's the same, they said something vague about one caliper being slightly stuck. I asked about copperease and they said they don't use it as it causes more problems they found, like seizing up of calipers cause it attracts a lot of dust and dirt. I cannot comment on that really. Is that cost cutting BS talk ?

They did say the only other thing is change the pads. I am not doing that, I don't expect to have to do that.

At times like these I wobble a bit about ownership, and why I bother trying to sort niggles out at expense with no solution. I still have yet to full learn that sweet spot between preventative maintenance and leaving well alone. I look after it as carefully as I can and it is still annoying. It was a squeak/squeal when feathering the brakes which is annoying, but you know the feeling of annoying things on a vehicle it just stops you from enjoying it, and now will spoil using the Bongo a bit cause I know I paid out for nothing, an annoying audible constant reminder.

I should not have pussy footed around and told them I wanted copperease on the back of the pads, given that is the only thing they have not done.

If there is one thing I dislike in life is paying money for F.A.

I should have just put up with it or told them I wanted copperease on if they did not put it on first time round, that is my mistake for being a
non assertive push over. Just to add I know any vehicle can cost money to maintain and repair so it is unfair to level expense only at Bongo ownership, cars cost money. And other vehicles are going to be much less enjoyable to own, although it is a tipping scale of balance in the end.

[Doone]

This may help you. https://www.thepartsalliance.com/delphi ... er-grease/

As he mentioned the sticking caliper then presumably he freed it and the squeal is because the surface is still uneven?

This link might also help: http://www.autoselectonline.com/article ... what-to-do

[teenmal]

Well I am peed off, paid £50.00 for nothing. Bloke said he cleaned everything and it's the same, they said something vague about one caliper being slightly stuck. I asked about copperease and they said they don't use it as it causes more problems they found, like seizing up of calipers cause it attracts a lot of dust and dirt. I cannot comment on that really. Is that cost cutting BS talk ?

They did say the only other thing is change the pads. I am not doing that, I don't expect to have to do that.

At times like these I wobble a bit about ownership, and why I bother trying to sort niggles out at expense with no solution. I still have yet to full learn that sweet spot between preventative maintenance and leaving well alone. I look after it as carefully as I can and it is still annoying. It was a squeak/squeal when feathering the brakes which is annoying, but you know the feeling of annoying things on a vehicle it just stops you from enjoying it, and now will spoil using the Bongo a bit cause I know I paid out for nothing, an annoying audible constant reminder.

I should not have pussy footed around and told them I wanted copperease on the back of the pads, given that is the only thing they have not done.

If there is one thing I dislike in life is paying money for F.A.

I should have just put up with it or told them I wanted copperease on if they did not put it on first time round, that is my mistake for being a
non assertive push over. Just to add I know any vehicle can cost money to maintain and repair so it is unfair to level expense only at Bongo ownership, cars cost money. And other vehicles are going to be much less enjoyable to own, although it is a tipping scale of balance in the end.

As I previously said , you might have a rouge pad, I would have taken the Mechanics advice and changed the pads if its annoying you that much. Front pads £20.00 and you would have something for your money. To be honest I never use any type of grease on the back of the pads, I just make sure that the shims/springs etc a refitted properly.

[Tony x]

Just to add...
In my experience the main cause of brake squeel is contamination. As well as sanding down the pads you also need to clean the disc. Although not visible the disc will have tiny particles of brake pad in them. Scrubbing with brake cleaner should sort it.
As a final note, some pads are designed to squeel when they're close to their service limit.

[Rup328]

Well I am peed off, paid £50.00 for nothing. Bloke said he cleaned everything and it's the same, they said something vague about one caliper being slightly stuck. I asked about copperease and they said they don't use it as it causes more problems they found, like seizing up of calipers cause it attracts a lot of dust and dirt. I cannot comment on that really. Is that cost cutting BS talk ?

They did say the only other thing is change the pads. I am not doing that, I don't expect to have to do that.

At times like these I wobble a bit about ownership, and why I bother trying to sort niggles out at expense with no solution. I still have yet to full learn that sweet spot between preventative maintenance and leaving well alone. I look after it as carefully as I can and it is still annoying. It was a squeak/squeal when feathering the brakes which is annoying, but you know the feeling of annoying things on a vehicle it just stops you from enjoying it, and now will spoil using the Bongo a bit cause I know I paid out for nothing, an annoying audible constant reminder.

I should not have pussy footed around and told them I wanted copperease on the back of the pads, given that is the only thing they have not done.

If there is one thing I dislike in life is paying money for F.A.

I should have just put up with it or told them I wanted copperease on if they did not put it on first time round, that is my mistake for being a
non assertive push over. Just to add I know any vehicle can cost money to maintain and repair so it is unfair to level expense only at Bongo ownership, cars cost money. And other vehicles are going to be much less enjoyable to own, although it is a tipping scale of balance in the end.

Sorry about your bad experience - I have used copperease when replacing brake pads on all my cars and motorbikes since I got my licence in 1979. None of them have ever suffered from brake squeal and I have owned 20 cars and over 40 motorbikes since that date.

[TheLongRoad]

Coppergrease is good on pad to caliperinterface silicon grease is best for Caliper slider bolts. The other thing is some pads have a little metal bit that hits the disc when the pads need replacement. Instead of a light on the dash you get a loud squeal.

[Bonneville]

It's the sliding surfaces where the pad 'ears' connect with the caliper body. There are stainless steel clips here which need cleaning until shiny. Then the crusty surfaces where they sit need scraping or dremelling back to smooth metal. Then re-assemble with a pad that uses a proper squeal shim preferably not Blueprint or similar price as these are at the cheap end of the market. Mintex or better. No grease other than on the sliding pads.