Brake pad help...WTF???
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Brake pad help...WTF???
I recently changed my 02's brake pads since it still had the OEM pads on and over 50k on the odometer... I purchased Cool Carbon pads after researching and reading reviews stating they were grippy, ultra-quiet and low dusting...
Well, 2 out of 3--they stop on a dime and the dust levels are waaay down. But now the damn car squeals like a city bus
I bedded the pads as best I could (there is NOWHERE around here that I can do several 70-20mph slow downs, etc...)--I did several 30-10 slowdowns without slamming the brakes. They now have 200 miles on them and sound like Mickey and Minnie Mouse on their wedding night 
Additionally, when I let off the brakes and continue to drive at slow speeds through my community, they continue to squeal on and off (not loudly, but it is noticeable at times with the windows down). Are the calipers not releasing correctly? Or are the pads just continuing to vibrate? WTF
One last thing--you guys that say you change out pads when you track and then go back to regulars when you're on the street--how in the world do you change them easily??? When I took out the OEM pads I literally had to pry the noise-dampeners off the pad--they were stuck on with some nasty adhesive. I did put the dampeners back inside the pistons, but without adhesive. Do you just not used adhesive? Not use dampeners at all? On the youtube videos it shows them simply sliding the pads out when the pistons are pressed back--I really had to work at getting those suckers out
Sorry for the lengthy post. I know someone on here will have a solution to my issues
Thanks guys!
Well, 2 out of 3--they stop on a dime and the dust levels are waaay down. But now the damn car squeals like a city bus
I bedded the pads as best I could (there is NOWHERE around here that I can do several 70-20mph slow downs, etc...)--I did several 30-10 slowdowns without slamming the brakes. They now have 200 miles on them and sound like Mickey and Minnie Mouse on their wedding night Additionally, when I let off the brakes and continue to drive at slow speeds through my community, they continue to squeal on and off (not loudly, but it is noticeable at times with the windows down). Are the calipers not releasing correctly? Or are the pads just continuing to vibrate? WTF
One last thing--you guys that say you change out pads when you track and then go back to regulars when you're on the street--how in the world do you change them easily??? When I took out the OEM pads I literally had to pry the noise-dampeners off the pad--they were stuck on with some nasty adhesive. I did put the dampeners back inside the pistons, but without adhesive. Do you just not used adhesive? Not use dampeners at all? On the youtube videos it shows them simply sliding the pads out when the pistons are pressed back--I really had to work at getting those suckers out
Sorry for the lengthy post. I know someone on here will have a solution to my issues
Thanks guys!
I think that most of us track guys have long since discarded the backing plates. Mine were gone when I bought my car.
30-10 is just not going to put enough energy into the system to get it hot enough to mate with the rotors. Remember that the energy dissipated in the brakes goes like the velocity squared. So, braking from 70->30 ~ 4900 - 900 = 4000; and 30->10 ~ 900 - 100 = 800. That means about 5 times as much heat energy into the rotors for 70->30 intervals as for 30->10.
If the pads are still making noise when you are not braking, that's another symptom of the same thing. Take a look at the rotors. You will probably see some shiny stripes and dull or even rusty stripes between them. You will know that you have the pads and rotors mated when the entire sweep of the pad is shiny.
Jon
30-10 is just not going to put enough energy into the system to get it hot enough to mate with the rotors. Remember that the energy dissipated in the brakes goes like the velocity squared. So, braking from 70->30 ~ 4900 - 900 = 4000; and 30->10 ~ 900 - 100 = 800. That means about 5 times as much heat energy into the rotors for 70->30 intervals as for 30->10.
If the pads are still making noise when you are not braking, that's another symptom of the same thing. Take a look at the rotors. You will probably see some shiny stripes and dull or even rusty stripes between them. You will know that you have the pads and rotors mated when the entire sweep of the pad is shiny.
Jon
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I think that most of us track guys have long since discarded the backing plates. Mine were gone when I bought my car.
30-10 is just not going to put enough energy into the system to get it hot enough to mate with the rotors. Remember that the energy dissipated in the brakes goes like the velocity squared. So, braking from 70->30 ~ 4900 - 900 = 4000; and 30->10 ~ 900 - 100 = 800. That means about 5 times as much heat energy into the rotors for 70->30 intervals as for 30->10.
If the pads are still making noise when you are not braking, that's another symptom of the same thing. Take a look at the rotors. You will probably see some shiny stripes and dull or even rusty stripes between them. You will know that you have the pads and rotors mated when the entire sweep of the pad is shiny.
Jon
30-10 is just not going to put enough energy into the system to get it hot enough to mate with the rotors. Remember that the energy dissipated in the brakes goes like the velocity squared. So, braking from 70->30 ~ 4900 - 900 = 4000; and 30->10 ~ 900 - 100 = 800. That means about 5 times as much heat energy into the rotors for 70->30 intervals as for 30->10.
If the pads are still making noise when you are not braking, that's another symptom of the same thing. Take a look at the rotors. You will probably see some shiny stripes and dull or even rusty stripes between them. You will know that you have the pads and rotors mated when the entire sweep of the pad is shiny.
Jon
http://www.braketechnology.com/brakepadbedding.html
Jon
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No, you haven't ruined the pads or the rotors. Just go out and gets some stops in. You will know when you get the pads hot because you will start to smell the binder coming off - kind of an organic chem lab smell. Here is a good guide to bedding brake pads:
http://www.braketechnology.com/brakepadbedding.html
Jon
http://www.braketechnology.com/brakepadbedding.html
Jon
Thank you for the quick replies Rep points for you 
Guess I know what I'm going out to do this weekend...gonna find an empty stretch of road and have some fun
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Watch this video about brake bed in. All will become clear.
http://www.essexparts.com/learning-center/Bed-in
After the video, to the left of the screen, it says "Learning Center". Click on "Choosing brake pads" and read.
http://www.essexparts.com/learning-center/Bed-in
After the video, to the left of the screen, it says "Learning Center". Click on "Choosing brake pads" and read.
Last edited by landjet; Jan 6, 2010 at 03:08 PM.
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Thread Starter
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Watch this video about brake bed in. All will become clear.
http://www.essexparts.com/learning-center/Bed-in
After the video, to the left of the screen, it says "Learning Center". Click on "Choosing brake pads" and read.
http://www.essexparts.com/learning-center/Bed-in
After the video, to the left of the screen, it says "Learning Center". Click on "Choosing brake pads" and read.
Thanks!
Do yourself a favor and grab a couple cans of brake cleaner at the autoparts store and get the car back in the air, taking each wheel off and putting a drain pan under each rotor/caliper... Careful with this stuff as it eats pain, floor, wheel, car, hell it'll eat the paint off of Joan Rivers' mug!
Spray the surface of the rotor completely and clean it all off well front and back before re-starting the process of bedding. You need to get the junk you put on off, so you can start fresh and be sure you'll get a good bedding this time around.
Mike
Spray the surface of the rotor completely and clean it all off well front and back before re-starting the process of bedding. You need to get the junk you put on off, so you can start fresh and be sure you'll get a good bedding this time around.
Mike
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Do yourself a favor and grab a couple cans of brake cleaner at the autoparts store and get the car back in the air, taking each wheel off and putting a drain pan under each rotor/caliper... Careful with this stuff as it eats pain, floor, wheel, car, hell it'll eat the paint off of Joan Rivers' mug!
Spray the surface of the rotor completely and clean it all off well front and back before re-starting the process of bedding. You need to get the junk you put on off, so you can start fresh and be sure you'll get a good bedding this time around.
Mike
Spray the surface of the rotor completely and clean it all off well front and back before re-starting the process of bedding. You need to get the junk you put on off, so you can start fresh and be sure you'll get a good bedding this time around.
Mike
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The sticky stuff on the back of the plate was probably anti-squeal. It's a rubbery substance meant to damp vibration although it probably also acts as an insulator which might not be cool either. Anyway, food for thought since you now have brakes that squeal heh...
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indeed I did watch the vid. I just can't imagine the dealer doing repeated 70- 30 stops with customer's cars
....or maybe they have a dyno in the back?