Rear Brake "whine/squeal"

[worzel]

Hi

This noise is definitely not pleasant.

Any owners with experience of what I can only describe as a squeal from the rear brakes. the intensity rises with speed although once running fast enough (say around 45mph plus) the regular pulse of the noise merges together. Have never experienced this before (I've owned the car for 35+ years). Sounds just like a wheel bearing running dry but- noise disappears as soon as I very lightly touch the brakes (not enough to actually slow the car).

Pushing the car backwards and forwards manually the noise (it's very high pitched) appears at a different pitch once every revolution of the wheel. Only one side appears to be affected- but it might be occurring on the other side too but I can't hear it because of the noise of the affected side.

I'm convinced it's the pad material- this is the first time I've used EBC pads. I've roughed up the pad surface (didn't work except for the first few hundred yards after which the noise returned).

Definitely no play in the wheel bearings and MoT test shows no problem with the rears on the rollers ie no sticking on or imbalance.

Pad material the problem- any opinions?

Regards

John

Discs are a matched pair and in any case have been on the car for around 15 years.

[Spyder fan]

Check your calipers are bolted firmly and that the pistons are not sticky. Other than that you may need new discs or just wait until the pads are bedded to their profile.



It's a slightly different thing, but my push bike has disc brakes and they used to squeal like a piggy, but the cure was brake cleaner from Muc Off http://www.halfords.com/webapp/wcs/stor ... yId_228374

They do one for motorcycle brakes, but don't mention cars, can't see it being the wrong thing to use for an Elan though. http://www.halfords.com/webapp/wcs/stor ... yId_165742

Good luck, hope it's a simple fix

[sutol45]

Had a problem myself with the rear EBC brake pads, very similar to your own.

With relatively new brake discs (1000-miles or so) I fitted a new set of EBC brake pads - they were terrible, as though supplied by the London Brick Company, and no way could I get them to bed-in.

Tried to source 'other' pads but EBC's were the only ones available (at that time).

Only alternative was to try another set of, you've guessd it, EBC brake pads. This time from a different supplier and these were perfect - bedded in in 50-miles or so.

I'd consider another set of brake pads John, maybe try Tony Thompson.

And even on this second set I had to fit some Mintex self-adhesive anti-squeal shims to reduce the noise and brake squeal (I'm having to do the same now on Audi RS3/TTRS brakes same problem 20-years on: Audi bless 'em are changing brake calipes, brake discs, brake pads, software... tsk!)

You should not discount a wheel bearing however, they do get noisy if: a) dry and/or b) start spinning in the alloy housing and then the housing starts to resonate.

PS: I owned my Elan for 37-years and maintained over 50-others... happy days

One thing for certain, the discs and or calipers ain't the problem!

[69S4]

Hi

Any owners with experience of what I can only describe as a squeal from the rear brakes. the intensity rises with speed although once running fast enough (say around 45mph plus) the regular pulse of the noise merges together. Have never experienced this before (I've owned the car for 35+ years). Sounds just like a wheel bearing running dry but- noise disappears as soon as I very lightly touch the brakes (not enough to actually slow the car).

I'm convinced it's the pad material- this is the first time I've used EBC pads. I've roughed up the pad surface (didn't work except for the first few hundred yards after which the noise returned).

I've had something similar for years although not quite as bad as you by the sound of things - either that or your hearing is better than mine

I've stripped and cleaned the calipers probably two or three times with no effect and it's survived a change of pads, although as I've only ever bought whatever Matty's supply as their std pads it's probably the same thing that's gone back in. It's not wheel bearings or discs - changed those, no effect, or loose bolts or worn bushes.

One thing I have noticed is that its worse when everything is dry and warm - like now. When the brakes are wet it vanishes so it should improve when it starts raining tomorrow. I've always assumed it was one pad not quite retracting quite as far as it should and just touching the disc as it ceases the instant I touch the brake pedal but none of the pads wear any quicker than the others, none of the pistons are sticking and varying amount of disc runout over the years hasn't made much (any) difference. It's not been a huge issue but it can bug you on a long run.

[sutol45]

It sure bugs you MORE on a NEW Audi RS3 Stuart, however, this wet/dry noise is EXACTLY the same - the moisture dampens out the noise. The rule at MIRA was to never bring a car for NOISE drive by evaluation on a dry day, TVR never did and they ALWAYS passed... on a WET day

[fatboyoz]

John,
If you decide you need shims to get rid of the squeal, have a look at my post here:
lotus-suspension-f42/rear-brake-pad-anti-squeal-shims-t29185.html
Regards,
Colin.

Hi

This noise is definitely not pleasant.

Any owners with experience of what I can only describe as a squeal from the rear brakes. the intensity rises with speed although once running fast enough (say around 45mph plus) the regular pulse of the noise merges together. Have never experienced this before (I've owned the car for 35+ years). Sounds just like a wheel bearing running dry but- noise disappears as soon as I very lightly touch the brakes (not enough to actually slow the car).

Pushing the car backwards and forwards manually the noise (it's very high pitched) appears at a different pitch once every revolution of the wheel. Only one side appears to be affected- but it might be occurring on the other side too but I can't hear it because of the noise of the affected side.

I'm convinced it's the pad material- this is the first time I've used EBC pads. I've roughed up the pad surface (didn't work except for the first few hundred yards after which the noise returned).

Definitely no play in the wheel bearings and MoT test shows no problem with the rears on the rollers ie no sticking on or imbalance.

Pad material the problem- any opinions?

Regards

John

Discs are a matched pair and in any case have been on the car for around 15 years.

[worzel]

Hi

Thanks for the input to date.

Now an update- here's a puzzler (I think).

I was pretty sure the wheel bearings were ok- but- anybody any ideas on this one?

My first check was to rock the wheel in a 6/12 oclock orientation. No play at all.
Used the car yesterday (the noise increase was noticeable on a 7 mile journey). Rocked the wheel again and now there's a noticeable clunk.

Removed the wheel with the base of the strut on a wooden block I levered upwards on the threaded part of the hub- definitely no noticeable movement.

Repeated this exercise but this time levered upwards on the base of the wheel mounting face of the hub thinking that levering further out from the bearings might show up something. No play discernible.

Replaced the wheel, rocked the wheel and now there was noticeable knock. Puzzled by now- so I removed the wheel, got a friend to lock the brake and checked the tightness of the hub retaining nut- wasn't loose.

Replaced the wheel, rocked it again and- no play!

I realised what was happening- on replacing the wheel I was rotating the hub to line up with the peg holes.

So- I replaced the wheel, rocked it and- the play/knock was back. Logic kicked in here- I marked the tyre at 12 oclock and rolled the car a bit. Rocked the wheel and the play/knock had reduced. Marked the wheel at 12 again.

Rolled the car a bit more- checked for the knock and it had disappeared.

My question- if the bearing really is at fault surely the knock would be present at all points thru a 360 revolution of the wheel ie it surely wouldn't disappear/reduce as it does.

I've had wheel bearings pack up before but any knock/play was always present and on the road any noise increased on corners and on every corner. Why is this knock intermittent?

Puzzled!

Regards

John

[worzel]

Hi

Thought it only fair to update my earlier post.

Complacency (on my part)- I never imagined that such an alarming clunking sound could be caused by fractionally loose bolts- in my case the 3 that bolt the disc to the outboard driveshaft and then to the doughnut. Each was tight- but obviously not quite enough. I tightened each probably no more than a 6th of a turn and the clonk has disappeared.

It remains to be seen if the other noise also vanishes- we'll see when I next use the car. Always check the obvious- don't assume anything. Should remember my own advice!

Regards and thanks to all for their input.

John