Ringing squeal noise from rear - ideas?

[Rory]

On daughters 2014 30K mile Jazz - any ideas what it might be?

It only seems to start once the car is faster than a crawl.  I noticed it as she drove off and got a brief chance to drive the car today and it seems to come and go randomly and be unaffected by braking or not.  She thought it was something in the boot!

I think there are audible wear indicators on the front pads - I've never heard them on any of our Jazzes but it was the same kind of noise I'd expect them to make, but I don't think they're on the rear pads and I wouldn't have expected the rears to go first.

Does Jazz have an electric fuel pump? I've heard of them squealing sometimes.

[John A]

A stone or something caught between the disc and it's guard?

[Rory]

Could be, but the sound had more of a ringing / tinkling to it than I'd have expected, although perhaps the guard rings.  I hope she hasn't run over a reindeer!

Apparently it's due to go in for the airbag recall so she'll get the dealer to investigate.  I'm bracing myself for being told it needs pads and discs all round - I couldn't get a good look at them today but they didn't seem too clever, although usually the dealers start pushing to replace at 50% and they weren't highlighted last service.

[culzean]

Could be, but the sound had more of a ringing / tinkling to it than I'd have expected, although perhaps the guard rings.  I hope she hasn't run over a reindeer!

Apparently it's due to go in for the airbag recall so she'll get the dealer to investigate.  I'm bracing myself for being told it needs pads and discs all round - I couldn't get a good look at them today but they didn't seem too clever, although usually the dealers start pushing to replace at 50% and they weren't highlighted last service.

Pad wear indicators start squealing at about 1.6mm left on pad

[Rory]

Pad wear indicators start squealing at about 1.6mm left on pad

Am I right in thinking they're only on the fronts?  And do you know if the squeal all the time, or only when braking?


Just occurred to me to search YouTube and there's a video on there which has more of scraping sound but the comments say it does sometimes sound like ringing, so that may well be it.

[culzean]

Pad wear indicators start squealing at about 1.6mm left on pad

Am I right in thinking they're only on the fronts?  And do you know if the squeal all the time, or only when braking?


Just occurred to me to search YouTube and there's a video on there which has more of scraping sound but the comments say it does sometimes sound like ringing, so that may well be it.

They are on both back and front pads, they look like a bit of shiny stainless bracket that sits over side of pad, 2 x photos on PDF attached - the bracket it more like a tuning fork and will 'squeal' loudly.

There is nothing on disc brakes to pull the pads away from disc (unlike drum brakes where there are strong springs to pull shoes clear away from drums, disc brakes always 'drag' even when your not pressing brake pedal), so depending on amount of wear the metal strip could rub on disc even when not braking.

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[fatlad]

On daughters 2014 30K mile Jazz - any ideas what it might be?

It only seems to start once the car is faster than a crawl.  I noticed it as she drove off and got a brief chance to drive the car today and it seems to come and go randomly and be unaffected by braking or not.  She thought it was something in the boot!

I think there are audible wear indicators on the front pads - I've never heard them on any of our Jazzes but it was the same kind of noise I'd expect them to make, but I don't think they're on the rear pads and I wouldn't have expected the rears to go first.

Does Jazz have an electric fuel pump? I've heard of them squealing sometimes.

*****************************
i had something similar.
it turned out to be a brake pad that had worn more than the other.

i thought it was a wheel bearing to start off with but alas a set of pads soon stopped it.

[Rory]

Well, daughter took car into the dealer yesterday for the airbag recall and to investigate the noise.

She rang me last night to say the dealer said they couldn't hear it!

I called the service manager this morning and asked if she dropped in could he have a listen.  He agreed, no problem, and she went in at lunchtime (was passing anyway).  He sent a tech out who heard the noise, looked at the car and pronounced that it's corrosion on the front discs and suggested replacing them.

I can't say it isn't that, but quite why it produces a quite loud "grabbing" noise (as if reversing with the handbrake not released) and then a ringing noise when going forwards is baffling to me.

[culzean]

Replacing front discs at 30K ?? Dealer looking for income again.

Pads could well be worn down in 30K especially if the caliper is sticking,  which means it will not equalise movement and the pad that sits on the piston (the inside pad) will wear much quicker than the outside pad.  30k is about right for pads (especially if used about town with lots of braking),  discs normally need replacing once every second set of pads.

[Rory]

It's not that they're worn, they said the disc was rusty.  I find that unlikely given that the car is used every day around town, so plenty of brake use.  At last service the fronts pads were reported as 20% worn and the rear 10% - although I have to say that both those figures seem a massive under-statement.  Just glancing at the outer pads I'd have said they're all at least 50% worn.

I just can't conceive of how the noise - especially the grabbing/rubbing noise in reverse when she backs out of our drive and really makes you wince - is caused by corrosion on the disk.  If it was that you'd think a few hard stops would fix it.  But that was the first thing I tried.

There's a well regarded ex-Honda indie in town - I might take it in there if I can get the car off her and see what they think.

[Kenneve]

+1. To Reply No1. re stone caught up between disc and disc guard.

[TopDown]

+2 to stone caught. Happened to us. Wife thought car was about to fall to bits.

Garage had a good laugh and cleared the stone out for nothing. She did go back with a box of biscuits for their teabreak though 

[Rory]

It's been doing it for 3 weeks now so I don't think it's going to be a stone.  I'd have hoped the garage might notice that if it was!

I did wonder if one of the guards was catching, but again would hope they'd see that.

It's the very fact that it's continued which is most surprising - I thought it would go away or get worse.

[culzean]

Rusty discs produce a grinding / dragging noise when brake is applied and make brakes very sharp and grabby. I had a road chip trapped between steel pad backplate and disc and it squealed like a banshee, but it did it all the time the wheel was moving,  I had to knock it out with a hammer and screwdriver.

[Rory]

I could be wrong, of course, but I'll be gobsmacked if the noises the car is making are caused by a rusty brake disk.