How do i quiet down these rear brakes?

[dem00n]

My rear pads keep squealing wherever i go. Even if i don't use the brakes, the pads screech against the rotor. At around 60 mph it'll be a steady sound that can be really annoying.

I've had this issue with the last set of pads i had, which were Project Mu HC 800+.

I currently have Winmax W4's, i actually bought these pads thinking i was only having the noise issue with the HC 800+.

I've bed in both sets according to the instructions and to other generic pad bedding instructions. I've gotten both sets smoking on the front rotors after I've done my last run.

I do track days and auto x so i do need a good set of "hybrid" pads, but these things seem like no difference than straight track pads. They make tons of noise and don't offer any "street" capabilities in that department.
I changed the hardware for all four corners when i switched to the W4's, so i know it's not that.


Now i have a theory (bare with me, i'm an Engineering student)....


The rear pads on this car are loose by nature, it is constantly skimming against the rotor whenever you drive the car. You can bed them and set that initial layer of material on the face of the rotor but since you drive around town , that bed will go away in days. When i bed them in, they'll be quiet for about one day, then after normal driving around town they'll come back squealing. The front rotors do not make noise, not even a peep.

What's the solution?

Should i run W3's on the rear? A less aggressive compound? I don't wanna loose the awesome braking capabilities, i get enough compliments on the stopping power of the car.

I can't stand the noise, it's embarrassing. People stare all the time because i'll roll by at 10mph screeching at everyone. The women don't stop complaining either.


Sorry for such a long post...this has been really bothering me.

[stevesnj]

Originally Posted by dem00n

My rear pads keep squealing wherever i go. Even if i don't use the brakes, the pads screech against the rotor. At around 60 mph it'll be a steady sound that can be really annoying.

I've had this issue with the last set of pads i had, which were Project Mu HC 800+.

I currently have Winmax W4's, i actually bought these pads thinking i was only having the noise issue with the HC 800+.

I've bed in both sets according to the instructions and to other generic pad bedding instructions. I've gotten both sets smoking on the front rotors after I've done my last run.

I do track days and auto x so i do need a good set of "hybrid" pads, but these things seem like no difference than straight track pads. They make tons of noise and don't offer any "street" capabilities in that department.
I changed the hardware for all four corners when i switched to the W4's, so i know it's not that.


Now i have a theory (bare with me, i'm an Engineering student)....


The rear pads on this car are loose by nature, it is constantly skimming against the rotor whenever you drive the car. You can bed them and set that initial layer of material on the face of the rotor but since you drive around town , that bed will go away in days. When i bed them in, they'll be quiet for about one day, then after normal driving around town they'll come back squealing. The front rotors do not make noise, not even a peep.

What's the solution?

Should i run W3's on the rear? A less aggressive compound? I don't wanna loose the awesome braking capabilities, i get enough compliments on the stopping power of the car.

I can't stand the noise, it's embarrassing. People stare all the time because i'll roll by at 10mph screeching at everyone. The women don't stop complaining either.


Sorry for such a long post...this has been really bothering me.

That's actually normal for the W4's, they are more of a track pad, I have the W2's and after a lot of research they seemed great for everyday and when I go to the track. I have done both and besides more brake dust they are quiet and capable. Switch to W2's, you may like them.

[canyons]

check for a lip at top of pad, these can form as pad wears away. Solution is to chamfer top of pad.

[Mr.ac]

Originally Posted by dem00n

Now i have a theory (bare with me, i'm an Engineering student)....

I see your problem..

Have you checked the rear shoe pads? My money is on worn out shoes.

[dem00n]

Originally Posted by canyons

check for a lip at top of pad, these can form as pad wears away. Solution is to chamfer top of pad.

Chamfer the corners you mean? I don't really understand what you mean.

[dem00n]

Originally Posted by Mr.ac

I see your problem..

Have you checked the rear shoe pads? My money is on worn out shoes.

I checked out the shoes before swapping in the W4's.

Even if it was the shoes,why would it get progressively louder the more you drive?

[dem00n]

Originally Posted by stevesnj

That's actually normal for the W4's, they are more of a track pad, I have the W2's and after a lot of research they seemed great for everyday and when I go to the track. I have done both and besides more brake dust they are quiet and capable. Switch to W2's, you may like them.

I might just try W2's on the rear. Thanks!

[ryoma]

I have W5's and they don't drag at all, though they do squeal sometimes on the street when coming to a stop which I don't really mind. are you sure your rear pistons were pressed in before installing the new pads? otherwise the difference in pad thickness might be causing the noise

[dem00n]

Originally Posted by ryoma

I have W5's and they don't drag at all, though they do squeal sometimes on the street when coming to a stop which I don't really mind. are you sure your rear pistons were pressed in before installing the new pads? otherwise the difference in pad thickness might be causing the noise

The noise is on both sides.

[cjd]

Don't stagger the pads...

Have you tried more traditional methods of quieting things like lube between the caliper and pad?

[canyons]

Originally Posted by dem00n

Chamfer the corners you mean? I don't really understand what you mean.

If there is a lip at top of pad, you need to grind it away. To prevent it from reforming, you can grind the top edge on a downward angle towards the rotor.

[dem00n]

Originally Posted by cjd

Don't stagger the pads...

Have you tried more traditional methods of quieting things like lube between the caliper and pad?

Yup, i even bought the heavy duty high temp brake lube. Nada

[Mr.ac]

Originally Posted by dem00n

I checked out the shoes before swapping in the W4's.

Even if it was the shoes,why would it get progressively louder the more you drive?

Engineer right? .......
Any way it's a bit hard to pin point with out seeing it in person. A few things off the top of my head it could be a bit of air on the rear lines making it stick, or a sticky caliper.

If you have the stock pads try swapping them. If the noise goes away then it's the pads. If not its some thing else.

If all else fails, bite the bullet and take it to a brake shop.

[dem00n]

Originally Posted by Mr.ac

Engineer right? .......
Any way it's a bit hard to pin point with out seeing it in person. A few things off the top of my head it could be a bit of air on the rear lines making it stick, or a sticky caliper.

If you have the stock pads try swapping them. If the noise goes away then it's the pads. If not its some thing else.

If all else fails, bite the bullet and take it to a brake shop.

Let's say it was the shoes. Correct me if i'm wrong, but if they wore down to the bare metal base, then that would be a metal on metal contact of the base to the inside of the rotor. That noise wouldn't increase through heat, you'd would have horrible screeching throughout the whole ride.


A brakes shops solution would be to buy their brake pads.

But i have yet to give on this. I'm pretty certain it's the pads, or it might even be a permanent cement on the rotor that's not causing it to bed properly. It could be many things, only way to find out is to swap things out.