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silent brakes - it can be done

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Old 03-02-2010, 04:53 PM
  #16  
NoVector
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Colin - Thank you. I was thinking about what Dr. Bob posted and resurfacing the rotors too. For whatever reason, new GTS front rotors are very expensive! And God knows, they're probably the same size as a Ford F-150 and availabe for $30 at NAPA... But I will definitely think about the PBR pads.

Bruce
Old 03-02-2010, 05:23 PM
  #17  
dr bob
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My concerns about rotor resurfacing only have to do with how much effort and time are required to bed in new pads. If the rotor surface is wavy/grooved, new flat-faced pads will only touch the hgh spots until they are worn in. The initial bedding-in process is then only effective on the small percentage of pad surface that actually touches the rotor. Rotors can develop hard spots from temperature differences under severe pressure/duty.

I'm generally not a big fan of having rotors resurfaced unless I can provide direct guidance to the 'expert' who's doing the work. I like to measure the rotors before they arrive for the work, again in front of the tech, and label each one with current thickness and target minimum turned thickness. If the rotors go to a high-volume shop, especially in a place that sells rotors, the easiest/laziest way for the tech to turn them is to choose a cutting depth that makes darn sure that he will only need one pass. He may sacrifice a lot of metal unnecessarily in his haste. The numbers and the verbal/written guidance let him know that the easiest/laziest way might not be the best way.
Old 03-03-2010, 02:02 AM
  #18  
GregBBRD
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Originally Posted by dr bob
My concerns about rotor resurfacing only have to do with how much effort and time are required to bed in new pads. If the rotor surface is wavy/grooved, new flat-faced pads will only touch the hgh spots until they are worn in. The initial bedding-in process is then only effective on the small percentage of pad surface that actually touches the rotor. Rotors can develop hard spots from temperature differences under severe pressure/duty.

I'm generally not a big fan of having rotors resurfaced unless I can provide direct guidance to the 'expert' who's doing the work. I like to measure the rotors before they arrive for the work, again in front of the tech, and label each one with current thickness and target minimum turned thickness. If the rotors go to a high-volume shop, especially in a place that sells rotors, the easiest/laziest way for the tech to turn them is to choose a cutting depth that makes darn sure that he will only need one pass. He may sacrifice a lot of metal unnecessarily in his haste. The numbers and the verbal/written guidance let him know that the easiest/laziest way might not be the best way.
I gave up on having rotors machined, years ago. I couldn't find anyone that could hold the .07mm specification for runout and I invariably ended up with a brake pedal that "bounced" under braking.
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Old 03-03-2010, 02:13 AM
  #19  
Lizard928
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I like Bob and GB do not resurface rotors on these cars.

I will only go with new rotors as once they need to be resurfaced, it is time for them to be replaced.

Esp with how I drive.
Old 05-05-2010, 07:03 PM
  #20  
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I followed this procedure and took some pics. Initially my brakes still made a horrible sound at low speeds so I removed the pads and reground with a new wheel on my bench grinder. Now the brakes are silent. The old wheel was to rough, I should of filed before installing.
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Old 05-05-2010, 08:31 PM
  #21  
blown 87
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Originally Posted by GregBBRD
I gave up on having rotors machined, years ago. I couldn't find anyone that could hold the .07mm specification for runout and I invariably ended up with a brake pedal that "bounced" under braking.
I sold my brake lathe 15 years ago.
Old 05-05-2010, 08:34 PM
  #22  
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Originally Posted by blown 87
I sold my brake lathe 15 years ago.
It seems that once they are warped they are done
Old 05-05-2010, 08:51 PM
  #23  
blown 87
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Originally Posted by Calgary Ole
It seems that once they are warped they are done
And they are so thin now, most are at the wear limit after one set of pads on most cars.

I got tired quick of having to redo jobs and replace rotors out of my own pocket.
Old 05-05-2010, 08:54 PM
  #24  
SQLGuy
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Ate blue? I had thought that blue was for non-ABS systems and gold for ABS? Not the case?
Old 05-05-2010, 09:14 PM
  #25  
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Blue and Gold are the same. The color is just to enable visual of when you bleed your brakes out with new fluid.
Old 05-05-2010, 10:02 PM
  #26  
928 at last
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OK Stupid Question Time.....
I should know this but...
Do you have to remove the calipers to change out the pads?
I just always have, so if there's another way.
Old 05-05-2010, 10:36 PM
  #27  
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No! compress the spring and a couple small taps with a wrench.
You can see it pulled away. The pads will come out with some wiggle
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Old 05-05-2010, 10:38 PM
  #28  
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Punp the brakes a couple times as they will be soft right after.
Old 05-05-2010, 10:44 PM
  #29  
the flyin' scotsman
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Originally Posted by 928 at last
OK Stupid Question Time.....
I should know this but...
Do you have to remove the calipers to change out the pads?
I just always have, so if there's another way.
You don't have to but it does depend on what the project entails.

To replace worn pads with new you'll have to push the caliper pistons back into the caliper to allow for the new thicker pads and the easiest method is to use a 'c' clamp with the caliper off.
Old 05-05-2010, 11:09 PM
  #30  
928 at last
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Thanks Guys!


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