Brake Squeal Issue

chuckbrandt · #1 (**permalink**) 03-12-2005, 06:29 PM

Hey Folks,
I have ERA #665 and have the ERA rear suspension and consequently the 12" Sierra brakes on the front. I've got about 130 miles on it and really since day one the brakes have squealed. I'm sure I've never worked them very hard. Any ideas on how to kill the squeal?

Thanks, Chuck

relaxinrob · #2 (**permalink**) 03-12-2005, 08:14 PM

The squeal is caused by vibration, sort of like a tuning fork. You need to disassemble the brakes and clean and lubricate each moving/sliding part. On the back of each pad, clean the back, then put a glob of clear silicone the size of a quarter in the middle of the back and allow it to dry. Once dry, reassemble and your squeal will be gone.

ERA Chas · #3 (**permalink**) 03-13-2005, 07:40 AM

Rob,
I have the same problem as Chuck and have tried the cleaning/lubing method many times. My noise happens when they are up to temp or HOT. They stop GREAT but make the high-pitched squeal while doing so. No fade either, they just keep biting harder.
I've also checked the caliper/rotor alignment and found it good with no "wedge" in the pads.
Could you explain the silicone application in more detail? I picture the two piston circles where they contact the pad and can't figure where you mean to apply the silicone. I assume you mean the silicone acts as a damper.
Thanks,

Bruce Edwards · #4 (**permalink**) 03-13-2005, 07:47 AM

The noise you hear is the pad vibrating. Adding Anti-Squeal that can be purchased at your local parts store will do a great job. Spread it on the REAR of the pad and install the pad in the caliper. The addition of the Anti-Squeal will act as a insulator between the pads metal backing and the caliper pistons.

ERA Chas · #5 (**permalink**) 03-13-2005, 07:56 AM

Bruce,
I have used every sort of anti-squeal and pad lube on the market. Even tried the type you spray on the rotor surface and followed instructions exactly.
All to no improvement.

Bruce Edwards · #6 (**permalink**) 03-13-2005, 08:11 AM

If that is the case you must have a rough spot on the brake pad surface. Pull the pads and sand them with some 80 grit to break the glaze on the pad surface. Use a bit of 220 and go over the rotor to give it a bit of roughness. Again you just want to break the glaze not reshape the parts. Check the backing plate on the pads. Look for uneven wear. A dished area on the end of one side of the pads shows uneven pressure on the pad.
All OEM pads now come with a anti-squeal insulator between the pad and the caliper pistons. The OEM part is a thin steal shim with an insulator on both sides.
Remember the pads must move smoothly in the caliper or it will hang and cause the pad to cock of center. Once that happens the caliper pistons will not press the pads evenly and you get a squeal.

relaxinrob · #7 (**permalink**) 03-13-2005, 09:11 AM

The silicone acts to absorb the vibrations. If you have a two-piston caliper, then apply two patches so they fit inside the caliper holes and find an area on the outside pad that does not interfere with anything. It works great!!! Are you using ceramic pads?

ERA Chas · #8 (**permalink**) 03-13-2005, 02:36 PM

Chuck- not trying to hi-jack your thread, but this is all valuable to you as well.
Bruce and Rob- Thanks for all your advice.
I've tried everything mentioned over time-EXCEPT the silicone idea.
Rob, the noise I get comes from my front 4-piston Wilwood Dynalites. The pads are Sierra 31-YF "soft". I believe they're carbon-metallic. Are you saying to apply silicone to the pad backs within the "circles" where the pistons contact the backing? Sorry I'm so dense and not quite understanding. Won't that prevent movement by the pads?
Appreciate your advice and patience!

chuckbrandt · #9 (**permalink**) 03-13-2005, 03:27 PM

No problem Chas. It sounds like we are in the same boat.

I got a spray squeak relief, disc brake quiet goop, and some clear rtv. Willing to try it all.

I'll let you know if any of it works.

Chuck

Bruce Edwards · #10 (**permalink**) 03-13-2005, 03:41 PM

If all else fails you could cut yourself a set of shims out of thin steel and coat it with anti-squeal and then install it between the pad and caliper.
The trick is in getting the pad backing to stop bouncing off the caliper pistons.
I am building a ERA with Wilwood brakes right now and will take a close look at the preassembled caliper and pad unit after hearing all the trouble you two are having. If I see anything funny I will let you folks know.
Good luck with yours and let us know what works.

relaxinrob · #11 (**permalink**) 03-13-2005, 06:16 PM

yes, the "quarter-sized" chunk of silicone should fit inside the caliper pistons.

Bruce Edwards · #12 (**permalink**) 03-13-2005, 07:18 PM

Ok I have never heard of putting silicone inside the caliper opening to fix a noise problem. The pad moving against the caliper piston edge is what makes the noise so how is adding some to the inside make it stop?
Sorry if I sound a bit thick but I have been building and working on cars for 30 years and never seen or heard of such a thing.
Always willing to learn something new

relaxinrob · #13 (**permalink**) 03-13-2005, 07:36 PM

Bruce and all,

The silicone goes on the back of the pad so that it fits up inside the caliper piston. It is attached to the back of the pad so that it absorbs any vibration created by the brakes and since the silicone is inside the caliper piston, it does not interfere with the normal operation of the braking system.

Bruce Edwards · #14 (**permalink**) 03-13-2005, 07:44 PM

Still not getting it. If you silicone the pad to the caliper piston I could understand how it would help for a time but only if you apply it to the piston edge were it makes contact with the pad.
The problem I have seen with silicone is that it is to soft and does not react well to the heat build up.

relaxinrob · #15 (**permalink**) 03-13-2005, 08:08 PM

the glob of silicone does not touch the caliper piston......it is stuck to the back fo the pad and is concealed inside the caliper piston. Since it is the pad that vibrates and squeals, the silicone glob on back of the pad absorbs the vibrations.....trust me, it works, try it, I have been doing this for years.

ERA Chas · #16 (**permalink**) 03-14-2005, 07:47 AM

Rob,
NOW I understand. Brake maintenance this week and will try the method. Of course, I don't know when I can test it thanks to east coast weather...
Thanks for explanation.

Ron Going · #17 (**permalink**) 03-14-2005, 09:03 AM

I've been reading all of your post about brake squeal. I have an ERA and had the same front brake squeal. I tried silicone and other anti-squeal goop from auto supply stores.....nothing worked. I have the big wilwood front brakes on my ERA 289 FIA. I called wilwood and ordered a set of shims made for my brakes. My part number was 300-8460 and a set of 4 cost about $13 plus shipping. Once installed between the pad and the pistons the noise was gone. CALL WILWOOD! The only problem that I had was because my brakes were new, the extra thickness with the shim made for a tight fit. But it's doable. Good luck.

strictlypersonl · #18 (**permalink**) 03-14-2005, 09:33 AM

Ron,

What material was the shim made from? Was it the same shape as the pad back?

Bruce Edwards · #19 (**permalink**) 03-14-2005, 09:59 AM

Ron, Thanks for clearing this up. The shim is the way to go.

chuckbrandt · #20 (**permalink**) 03-14-2005, 11:53 AM

My calipers say Sierra on them, is that the same as wilwood or not?

Sorry, probably a dumb question.

Chuck