Brake Disc Life
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Brake Disc Life
So I have just ordered a full set of Pagid RS29 Yellow Pads from Dan @ Vivid (seriously high end for brake pads ! OEM on GT3) now my front brake discs were replaced at circa 30,000 miles and on my rear brake discs (40,000 miles) there is a noticeable lip on the edge of the disc, where it has worn down since new BUT the rear disc itself is perfectly smooth. Should I replace the rear discs too now with the new pads or can they last much longer ?? My front discs were only replaced as on a long trip the pads went down to the limit and grooved (blame my Porsche Dealer for that!)
Last edited by RCH; May 17, 2010 at 11:01 AM.
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It's better to bed new pads on old rotors, don't ask me why because i don't know, but that is what I've read from a number of brake sites. Now as far as the rear rotors, smoothness or a lip is not the issue, but disc thickness and cracking between the holes is. Have this checked out and then make your decision.
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It's better to bed new pads on old rotors, don't ask me why because i don't know, but that is what I've read from a number of brake sites. Now as far as the rear rotors, smoothness or a lip is not the issue, but disc thickness and cracking between the holes is. Have this checked out and then make your decision.
The specs are as follows:
Rotor thickness front: New = 34mm, Wear limit = 32mm
Rotor thickness rear: New = 28mm, Wear limit = 26mm
I recall that the spec is to replace the rotors if cracks are over 7mm long, but I couldn't find that in the manual at the moment.
Edit: If you have to ask, you don't have the cracks. They are quite obvious to the naked eye. They come from heat cycling, so if you don't track your car, you may never see them.
Jon
Rotor thickness front: New = 34mm, Wear limit = 32mm
Rotor thickness rear: New = 28mm, Wear limit = 26mm
I recall that the spec is to replace the rotors if cracks are over 7mm long, but I couldn't find that in the manual at the moment.
Edit: If you have to ask, you don't have the cracks. They are quite obvious to the naked eye. They come from heat cycling, so if you don't track your car, you may never see them.
Jon
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Only 2mm allowance for wearing.
The specs are as follows:
Rotor thickness front: New = 34mm, Wear limit = 32mm
Rotor thickness rear: New = 28mm, Wear limit = 26mm
I recall that the spec is to replace the rotors if cracks are over 7mm long, but I couldn't find that in the manual at the moment.
Edit: If you have to ask, you don't have the cracks. They are quite obvious to the naked eye. They come from heat cycling, so if you don't track your car, you may never see them.
Jon
Rotor thickness front: New = 34mm, Wear limit = 32mm
Rotor thickness rear: New = 28mm, Wear limit = 26mm
I recall that the spec is to replace the rotors if cracks are over 7mm long, but I couldn't find that in the manual at the moment.
Edit: If you have to ask, you don't have the cracks. They are quite obvious to the naked eye. They come from heat cycling, so if you don't track your car, you may never see them.
Jon
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I agree 2mm of wear can't be right. Cracks are a problem if..
they are thick enough to catch your fingernail. And yes you might not ever see them unless u track the car. If you do check the inside of the rotor as well.
Manual pages attached. No spec on fingernails, just the numbers I put in my first post. I agree that it doesn't seem like much. I usually go by the length of the cracks for replacing mine.
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So I have just ordered a full set of Pagid RS29 Yellow Pads from Dan @ Vivid (seriously high end for brake pads ! OEM on GT3) now my front brake discs were replaced at circa 30,000 miles and on my rear brake discs (40,000 miles) there is a noticeable lip on the edge of the disc, where it has worn down since new BUT the rear disc itself is perfectly smooth. Should I replace the rear discs too now with the new pads or can they last much longer ?? My front discs were only replaced as on a long trip the pads went down to the limit and grooved (blame my Porsche Dealer for that!)
I would recommend a set of GircoDisc slotted rotors for your particular application. They will provide much better braking and the wear tolerances are also much greater then the OE rotors are well.
** The image displayed ( slotted & drilled )
Please pm me for details and pricing
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I would recommend a set of GircoDisc slotted rotors for your particular application. They will provide much better braking and the wear tolerances are also much greater then the OE rotors are well.
** The image displayed ( slotted & drilled )
Please pm me for details and pricing
** The image displayed ( slotted & drilled )
Please pm me for details and pricing