Marc Shaw

Recently, I changed my rotors to drilled Zimmermans and pads to Ferodo (street version). I've been braking gently to let the pads seat well and to allow the rotors and pads to "break in" gently (pun intended!).

Yesterday, I started to get a nasty squeal from the front - not sure which side. It is only while rolling at slow speed, it is un-related to engine speed but it is related to car speed. It is intermittent, like a pad contacting the rotor at one part during the rotation, and goes away when the brake is applied.

Is this a normal part of pads getting seated in or is there a problem? I don't think I would have warped the rotor as I've driven very gently since putting the new brakes on. I did apply sticky backed anti-squeal to the pads too.

Thanks.......Marc

Rennen

I think you're doing the exact wrong thing to bed the pads. You need to hammer those pads hard on consecutive stops, like maybe 10 in a row, to heat them up a LOT. This cooks the impurities out of the pads and distributes the pad materials evenly onto the rotor which is extremely important. Then drive for a while to cool them down and hammer them again the same way. Bring the car down from 60MPH to almost stopped but not completely.

You should read this article on the StopTech site about the theory of brake pad seating and exactly what you're trying to accomplish.

jimq

Maybe you need to go back to the factory squeal hats that snap in the pistons. cost $20 or so a wheel. Gets a bit pricy for simple little parts. Another trick I read was to bevel the edge of the pad.

Marc Shaw

RedRS - you are probably right about bedding the pads but the rotors came with instructions that specifically said to avoid hard stop for the first 300 miles to avoid "glazing" the surface and permanently damaging it....now I'm not sure what to do. I'm sure I'm not the first person to change pads and rotors at the same time!

Jim - I considered that but it makes changing the pads such a huge PITA as those little hats stick in the caliper pistons and prevent easily pulling the pads out. If it continues to squeal, I just may do that.

On a related note, I went for a drive this morning and no noise at all. Yesterday, it started squealing after driving stop and go for about an hour (traffic and looking for an address) - could it be a heat related squeal issue? As the pads get hot, they get noisy? I would have throught it should be the other way around - once hot, they are softer and less noisy.

Marc

Rennen

Don't the Ferodos already have an anti-squeal pad attached to the back? I don't think I'd double those up.

Bill Wagner

Marc:
it sounds to me sort of like your pistons are sticking a little...it might just go away on its own. When was the last time you changed the brake fluid?


Indycam:
What brand were the anti-squeal pads you guys have, where did you get them, and how much were they? Did you "bag" the anti-squeal "mushrooms" or "hats" as they're often called, or did you use then along with the anti-squeal pads?

Euromagination

Marc,

Ironically, my car is doing this same exact thing, but my pads aren't new. Let me know how that brake fluid change goes.

Bill Wagner

Thanks, guys! I've been fooling with the squeal on and off for years now, and I've pretty much come to the conclusion that on least some cars they're more responsible for CREATING squeal rather than eliminating it! I was considering a combo of metal masters along with the anti-squeal dampers that Pelican sells and bagging the "mushrooms" forever.

Thanks again!!