Brake Pad Change...Unhappy :X
10-10-09, 09:13 AM
#61
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just wanted to add my .02
last winter maybe 3-4 months after picking up my F I took it back to the dealer and btched about the squeal and they cut my rotors and installed new front pads for free....drove out of the dealer..squealed right away, lol
tried bedding them in...worked for a few days then squeal came back...
finally a few months ago I installed the Carbotech Bobcats myself without changing or cutting rotors and the squeal is gone (and the dust!!)
last winter maybe 3-4 months after picking up my F I took it back to the dealer and btched about the squeal and they cut my rotors and installed new front pads for free....drove out of the dealer..squealed right away, lol
tried bedding them in...worked for a few days then squeal came back...
finally a few months ago I installed the Carbotech Bobcats myself without changing or cutting rotors and the squeal is gone (and the dust!!)
10-10-09, 10:05 AM
#62
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... In my case they said that rotors were in great shape and I had to worry only about pads, rotors were fine as is. Of course I followed their advise and replace the pads only, but I went with Hawk ceramics trying to avoid brake dust. Again my only complain is that bad looking rust ring.
Did you ever do a proper "bed in procedure" after the new pads went in?
Joe Z
10-10-09, 10:55 AM
#63
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Maybe this will help with visualizing what I'm talking about. Did a quick drawing of why you want to have your rotors turned or use new ones. The top is what you should have when you do a brake job. The bottom is what you probably have if you just install pads on a used rotor without turning it. It may look flat while looking at it, but it most likely isnt. So when you put new pads on, you get uneven contact with the rotor until the pad wears down. That rust ring will most likely go away after the pad wears down a bit and makes full contact with the rotor. The angle I drew is a little exaggerated to get the point across.
10-11-09, 11:44 AM
#65
When I took my IS-F to the dealer (before doing the brake job) they checked both front and rear brakes, they said that rears were fine at 7mm or 8mm (don't remember exactly), but fronts were at 3mm and I should change pads soon. They inspected the front rotors and said that in many cases the rotors need to be replaced, but they may cut them if it's still possible. In my case they said that rotors were in great shape and I had to worry only about pads, rotors were fine as is. Of course I followed their advise and replace the pads only, but I went with Hawk ceramics trying to avoir brake dust. Again my only complain is that bad looking rust ring.
just wanted to add my .02
last winter maybe 3-4 months after picking up my F I took it back to the dealer and btched about the squeal and they cut my rotors and installed new front pads for free....drove out of the dealer..squealed right away, lol
tried bedding them in...worked for a few days then squeal came back...
finally a few months ago I installed the Carbotech Bobcats myself without changing or cutting rotors and the squeal is gone (and the dust!!)
last winter maybe 3-4 months after picking up my F I took it back to the dealer and btched about the squeal and they cut my rotors and installed new front pads for free....drove out of the dealer..squealed right away, lol
tried bedding them in...worked for a few days then squeal came back...
finally a few months ago I installed the Carbotech Bobcats myself without changing or cutting rotors and the squeal is gone (and the dust!!)
10-11-09, 08:31 PM
#66
Hey Joe, what I always do with my cars when I replace pads is to gently brake a couple of times from 60 MPH, then I do a couple of series of hard braking from 60 to 10, but not locking up the brakes nor engaging the ABS or coming to a full stop. Then I drive normal trying not to use the brakes too much (so they can cool down). After 5 to 10 minutes my brakes are ready to be used in normal way.
10-11-09, 11:36 PM
#67
Tech Info Resource
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1. There is no US LSB for brakes or brake pads.
2. "Turning" a rotor with holes in it is dumb. It should be centerless ground. The holes make an interrupted cut on a lathe and the discs will never be flat again. Lathe cutting also leaves micro-burrs that wear pads much faster than a disc ground with stones. Even stones leave burrs, but they're much smaller and the surface RA is much better with stones vs. lathe cutting.
3. Resurfacing a rotor with 2mm of service life means you're sacrificing 12.5% of the available metal with a 0.010" (typical) resurfacing operation.
4. Rotors don't warp. They get uneven pad deposits, but they don't warp. If there's anyone here who thinks Carroll Smith doesn't know what he's talking about, I'd sure like to hear it:
5. IME with cars and bikes for street and track over the last 30 years or so, the lip at the edge of the disc is there because the pad doesn't contact the disc at the edge. If the pad doesn't contact the rotor as evidenced by the lack of wear, how could it possibly keep the new pad from contacting the rotor? Check the old pad coming off...there is no bevel at the top edge where the disc has it's lip.
2. "Turning" a rotor with holes in it is dumb. It should be centerless ground. The holes make an interrupted cut on a lathe and the discs will never be flat again. Lathe cutting also leaves micro-burrs that wear pads much faster than a disc ground with stones. Even stones leave burrs, but they're much smaller and the surface RA is much better with stones vs. lathe cutting.
3. Resurfacing a rotor with 2mm of service life means you're sacrificing 12.5% of the available metal with a 0.010" (typical) resurfacing operation.
4. Rotors don't warp. They get uneven pad deposits, but they don't warp. If there's anyone here who thinks Carroll Smith doesn't know what he's talking about, I'd sure like to hear it:
Originally Posted by Carroll Smith
In fact every case of "warped brake disc" that I have investigated, whether on a racing car or a street car, has turned out to be friction pad material transferred unevenly to the surface of the disc. This uneven deposition results in thickness variation (TV) or run-out due to hot spotting that occurred at elevated temperatures.
10-15-09, 08:58 PM
#70
1. There is no US LSB for brakes or brake pads.
2. "Turning" a rotor with holes in it is dumb. It should be centerless ground. The holes make an interrupted cut on a lathe and the discs will never be flat again. Lathe cutting also leaves micro-burrs that wear pads much faster than a disc ground with stones. Even stones leave burrs, but they're much smaller and the surface RA is much better with stones vs. lathe cutting.
3. Resurfacing a rotor with 2mm of service life means you're sacrificing 12.5% of the available metal with a 0.010" (typical) resurfacing operation.
4. Rotors don't warp. They get uneven pad deposits, but they don't warp. If there's anyone here who thinks Carroll Smith doesn't know what he's talking about, I'd sure like to hear it:
5. IME with cars and bikes for street and track over the last 30 years or so, the lip at the edge of the disc is there because the pad doesn't contact the disc at the edge. If the pad doesn't contact the rotor as evidenced by the lack of wear, how could it possibly keep the new pad from contacting the rotor? Check the old pad coming off...there is no bevel at the top edge where the disc has it's lip.
2. "Turning" a rotor with holes in it is dumb. It should be centerless ground. The holes make an interrupted cut on a lathe and the discs will never be flat again. Lathe cutting also leaves micro-burrs that wear pads much faster than a disc ground with stones. Even stones leave burrs, but they're much smaller and the surface RA is much better with stones vs. lathe cutting.
3. Resurfacing a rotor with 2mm of service life means you're sacrificing 12.5% of the available metal with a 0.010" (typical) resurfacing operation.
4. Rotors don't warp. They get uneven pad deposits, but they don't warp. If there's anyone here who thinks Carroll Smith doesn't know what he's talking about, I'd sure like to hear it:
5. IME with cars and bikes for street and track over the last 30 years or so, the lip at the edge of the disc is there because the pad doesn't contact the disc at the edge. If the pad doesn't contact the rotor as evidenced by the lack of wear, how could it possibly keep the new pad from contacting the rotor? Check the old pad coming off...there is no bevel at the top edge where the disc has it's lip.
10-19-09, 07:35 AM
#71
As I said before my brakes are fine except for the ugly rust ring. No noise and great stopping power. This is the last response received from Hawk about this issue, in other words contacting them was a waste of time:
So they ignored the most important part, the pad not being fully in contact with the rotor.
I have reviewed the pictures and looked over your response. The hot spots that you are noticing is an uneven layer of transfer material from the pads. what I would recommend is that you make 8 stops with medium pedal pressure from 35 to 0. Then make 4 hard stops from 45 to 0. Allow the brake system to cool for about 20 minutes. This should help in smoothing out the transfer layer. If you have any questions please feel free to contact me. Thank you
10-19-09, 02:45 PM
#72
As I said before my brakes are fine except for the ugly rust ring. No noise and great stopping power. This is the last response received from Hawk about this issue, in other words contacting them was a waste of time:
So they ignored the most important part, the pad not being fully in contact with the rotor.
So they ignored the most important part, the pad not being fully in contact with the rotor.
^^^