Hollywood Posted April 30, 2011 Share Posted April 30, 2011 (edited) I've had some brake work done on a 95 TT recently for the purpose of fixing a screech at low speeds(was a shimming issue, had to machine it down after new pads were replaced), it still has an odd sound that seems brake related[EDIT after testing again, most assuredly sounds like the brakes]. This is going to be a hard sound to describe. Imagine a rock grinding wheel(old style, not a modern machine) for sharpening blades that goes in a circular motion and as the wheel goes around against the blade, or a sprinkler system, or the effect noise you hear when they advertise Santa's sleigh bells (http://www.youtube.com/watch?v=ibnJVjw27OQ) but not so POPPY and not as fast; It's more of a slow "sssss sssss sssss" sound, but not as fast as if you'd blown a head gasket. But in short, the "ssss sssss" sound is like if something metal or similar to metal was spinning, and another metal piece was just barely rubbing up against the rotating metal piece. It's most noticeable when driving by a wall where the sound reverberates. And until today I hadn't heard any difference when applying the brakes. Unfortunately now when applying the brakes at any moderate speed or higher(20+) the sound becomes even more pronounced and obvious. The shop keeps telling me they can't hear it, even when they go on a 'test drive.' Brakes 'feel' fine, and respond ok for JDM. It's probably the pads, possibly because they are new but what worries me is the thought that the sound means maybe the pad IS really stuck or worse, the disc is damaged in someway and slowly grinding away whenever the vehicle is in motion. Probably not a MKIV specific issue, but thoughts are welcome. Note: I have a set of 17" non factory wheels which seem to be in appropriate balance and fitted properly. However I suppose it's possible there's an offset issue, maybe inside of wheel is hitting control arm? I don't have the option to look and take care of this stuff myself anymore, so a lot of it is guess work for now. Thanks, Holly Edited April 30, 2011 by Hollywood (see edit history) Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted April 30, 2011 Share Posted April 30, 2011 Is the dust sheild catching the disc? Quote Link to comment Share on other sites More sharing options...
nevins Posted April 30, 2011 Share Posted April 30, 2011 As above or possibly the anti sequel plate on the rear of the pad has slipped and running on the bell (centre ) of the disc, I have had a few cars with this. Quote Link to comment Share on other sites More sharing options...
Hollywood Posted May 1, 2011 Author Share Posted May 1, 2011 Hi gentleman, thank you. When I have a chance to get under it, or take it in, I will mention this to them. I am hoping it's just a new thick/oversized pad rubbing and will wear itself down in a few weeks. Holly Quote Link to comment Share on other sites More sharing options...
Nic Posted May 1, 2011 Share Posted May 1, 2011 was a shimming issue, had to machine it down after new pads were replaced. Were new anti squeal shims fitted? What pads are you using? Which brakes do you have - the larger 4pot/2pots brakes or the smaller 2pot/1pot ones? Check that a caliper(s) aren't sticking, with you hand check the temperature of each wheel after a drive, if a caliper is sticking then that wheel will be significantly hotter. Is the dust sheild catching the disc? or stone caught between shield and disc. Quote Link to comment Share on other sites More sharing options...
Scooter Posted May 1, 2011 Share Posted May 1, 2011 (edited) er what Nic said! In the mean time, I would check each alloy after each drive to see if one is getting hot. A sticking caliper can drag to an extend where the disk gets exceptionally hot which is not good for the caliper or disk. If the wheels are all similarly warm after a run and the brakes are working fine then i'd be happy it was something relatively minor. Edited May 1, 2011 by Scooter duplicate of Nic advice (see edit history) Quote Link to comment Share on other sites More sharing options...
Hollywood Posted May 2, 2011 Author Share Posted May 2, 2011 I don't think 'anti-squeal' shims were fitted, but it's definitely reduced the screech. The brakes I thought were 2pot. I haven't had it off here at my place, and I haven't been under it at the shop to see what exactly is going on. I thought it might be caliper related, but none of the wheels have felt noticeably warm nor do I get any burning smell. I'll keep an eye and nose out while I test my pad theory. Should I decide to give up and just replace them, what's a UK assembly cost these days? Quote Link to comment Share on other sites More sharing options...
jagman Posted May 2, 2011 Share Posted May 2, 2011 Dont they use a squeel shim that makes noise when the pads are low as a warning , could this be causing the noise ?-take it out ! Quote Link to comment Share on other sites More sharing options...
Nic Posted May 2, 2011 Share Posted May 2, 2011 I don't think 'anti-squeal' shims were fitted, but it's definitely reduced the screech. If you don't have the stock brake pad shims on the front the brakes will be noisy. Not a problem on the rear, the shims can be removed - for better brake feel - without them being noisy. Quote Link to comment Share on other sites More sharing options...
Jimmy James Posted May 2, 2011 Share Posted May 2, 2011 I just had a caliper stick and didnt know till the disc cracked in three places and was undrivable.. Not a good experiance. Quote Link to comment Share on other sites More sharing options...
Hollywood Posted May 9, 2011 Author Share Posted May 9, 2011 Yes, I am hoping it's not a stuck caliper. Now the popping noise when applying the brake at lower speeds or creeping forward is getting more frequent and more audible. Someone told me it was the bushings down underneath but I don't know. Think I might take it elsewhere for a second opinion if it comes to that. Quote Link to comment Share on other sites More sharing options...
bodilx6 Posted May 10, 2011 Share Posted May 10, 2011 I've got a shot at this: Is it from the rear brakes? If so, I'm almost certain that it is due to the brake shoes in the parking brake catching the spring inside the brake housing. You've got two "U"-shaped metal thingy's which holds a spring used to keep the shoes away from the center part of the rear brake disc. This tend to bend over time, thereby catching something on the inside of the brake disc/bare shoe housing. You can easily check this by unbolting the wheel and rotating it. It's also an easy fix if you can get the disc off. If they are the reason, you can just bend them back into shape and reinsert them. Might be a bit fiddlely but easy none the less. Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted May 10, 2011 Share Posted May 10, 2011 Where abouts are you? Maybe someone local could have a look for you? Quote Link to comment Share on other sites More sharing options...
Hollywood Posted May 12, 2011 Author Share Posted May 12, 2011 I've got a shot at this: Is it from the rear brakes? If so, I'm almost certain that it is due to the brake shoes in the parking brake catching the spring inside the brake housing. You've got two "U"-shaped metal thingy's which holds a spring used to keep the shoes away from the center part of the rear brake disc. This tend to bend over time, thereby catching something on the inside of the brake disc/bare shoe housing. You can easily check this by unbolting the wheel and rotating it. It's also an easy fix if you can get the disc off. If they are the reason, you can just bend them back into shape and reinsert them. Might be a bit fiddlely but easy none the less. It's hard to say if the 'ssss ssss' sound comes from the rear or the front. I'm trying to get others to drive it around so I can hear from outside the car too. I'm almost resigned to the idea that it might be large pads but, I like your idea as someone outside of the forums mentioned that parking break shoes might be the culprit to some degree. Also I previously mentioned a knock, pop sound and how it could be wishbone bushings. That's probably what I experience when doing three point turns but the brake popping happens when I'm slowing down from a moderate 20 miles an hour, and lightly hold the brake pedal in a fixed position till the car stops. From the front to the rear of the vehicle I can hear a pop, pop, pop almost in a very even tone. Unfortunately when I took it to the mechanics and drove one of them around, it NEVER happened(except when I left the house on the way to the mechanics..go figure). This popping thing has become my obsession now. ;/ Time for a second opinion. Quote Link to comment Share on other sites More sharing options...
bodilx6 Posted May 13, 2011 Share Posted May 13, 2011 I've got a knock/pop sound as well. But that is from the rear suspension and has been with the car since I got it 5 years ago through 3 types of damper/spring configurations.. More prone in the wet.. Go figure.. I don't drive it in the wet anymore and have given up figuring it out as it cannot be reproduced deliberatly.. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 14, 2011 Share Posted May 14, 2011 If the pads or calipers are sticking on one wheel that wheel will get very much hotter than the others due to the friction. Quote Link to comment Share on other sites More sharing options...
Hollywood Posted May 19, 2011 Author Share Posted May 19, 2011 Yes the brakes would be hot, but they are not overly hot - not racing/track hot. But since I've only been driving it a few miles a day, I don't think the brakes get used enough to start smoking or seem so hot it's obvious. Bodilx, you now that could be wishbone related. You're sure it's from the rear only? And it happens when applying the brake? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.