Brake fade question
03-27-2012, 03:26 PM
#1
Brake fade question
I had installed new OEM Porsche rotors-pads and upgraded to steal lines... (yes realize the stock lines are of high quality).... this was done at a very reputable all Porsche local shop. Brakes did not bite the same since... Let a season pass. Brought the car into my dealer for normal maintenance due, oil change, other and had them flush brake fluid etc..
Picked up the car and tested the brakes... Brakes the worse they have ever felt...at 60mph on brakes hard and car slows and then off the brakes at about 25mph, speed up to again to 60mph range and on the brakes hard again....brake pedal stiff and once pressure applied seems to have lost at least half its stopping power.....off brakes and then at 25mph try for 3rd braking attempt to stop the car and brake fade loss near 80% as car comes to a slow rolling stop.....
Something is just not right, dealer can not seem to find it.... any feedback greatly appreciated... Thanks
Picked up the car and tested the brakes... Brakes the worse they have ever felt...at 60mph on brakes hard and car slows and then off the brakes at about 25mph, speed up to again to 60mph range and on the brakes hard again....brake pedal stiff and once pressure applied seems to have lost at least half its stopping power.....off brakes and then at 25mph try for 3rd braking attempt to stop the car and brake fade loss near 80% as car comes to a slow rolling stop.....
Something is just not right, dealer can not seem to find it.... any feedback greatly appreciated... Thanks
03-27-2012, 04:00 PM
#2
Poseur
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That is precisely why I usually have sticked to the OEM set up. The OEM Brembo brakes are engineered to work together with the entire brake assembly--when you change a component, you have altered the configuration. Can you retrieve the OEM lines?
03-27-2012, 05:00 PM
#4
Race Director
I had installed new OEM Porsche rotors-pads and upgraded to steal lines... (yes realize the stock lines are of high quality).... this was done at a very reputable all Porsche local shop. Brakes did not bite the same since... Let a season pass. Brought the car into my dealer for normal maintenance due, oil change, other and had them flush brake fluid etc..
Picked up the car and tested the brakes... Brakes the worse they have ever felt...at 60mph on brakes hard and car slows and then off the brakes at about 25mph, speed up to again to 60mph range and on the brakes hard again....brake pedal stiff and once pressure applied seems to have lost at least half its stopping power.....off brakes and then at 25mph try for 3rd braking attempt to stop the car and brake fade loss near 80% as car comes to a slow rolling stop.....
Something is just not right, dealer can not seem to find it.... any feedback greatly appreciated... Thanks
Picked up the car and tested the brakes... Brakes the worse they have ever felt...at 60mph on brakes hard and car slows and then off the brakes at about 25mph, speed up to again to 60mph range and on the brakes hard again....brake pedal stiff and once pressure applied seems to have lost at least half its stopping power.....off brakes and then at 25mph try for 3rd braking attempt to stop the car and brake fade loss near 80% as car comes to a slow rolling stop.....
Something is just not right, dealer can not seem to find it.... any feedback greatly appreciated... Thanks
Did you perform a brake bedding in after installing the new brake pads/rotors?
OEM is not the same as OE. The new pads/rotors may just not have the same brake performance as the OE pads/rotors.
While you use the term brake fade it is hard to image the brake hardware so crummy as to experience fade from the heating from what is rather mild braking.
Thus, what you may be experiencing is lack of brake boost which requires more pedal effort which can feel like the brakes are fading.
If the boost is down, or if possibly the new steel brake likes are routed/shaped differently there's the possibility a standard Porsche brake fluid flush/bleed will not remove all the air from the system.
In this case the power bleed system used by the dealer may not be up to the task. Hard to believe though, for this system is used to flush/bleed brake systems that are bone dry, after the brake hardware is replaced.
But assuming the worst, one possible tack would be to do a brake flush/bleed using the old manual method.
Now if not done right, this can make things worse, for it can make one believe the bleed is not the problem when in fact it is.
Also be aware it is not a good idea to fully depress the brake pedal all the way down when bleeding the brakes this way for this puts the master cylinder piston into a area of the master cylinder it has probably never been in before. This area can have dirt or corrosion present either of which can damage the piston and its seal with the cylinder.
Sincerely,
Macster.
03-27-2012, 05:13 PM
#5
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Plenty of guys upgrade their brake lines to stainless steel braided design. The brake lines simply convey the hydraulic pressure to the pistons of the brake calipers. The better the conveyance components the better feedback you get at the pedal and perhaps better performance. Brake fade happens when the pads exceed their design temperature which happens during hard braking. Unless you're on the track or jamming down a mountain side at brake neck speeds I don't think you'll ever see brake fade on your Porsche. The car is made for speed so the brakes are designed to stop.
Check for air in the lines and check for brake fluid on the rotors. What you are explaining is not normal but I highly doubt that the brake lines have anything to do with the problem. If the brakes got worse after the flush then take the car back so the dealer can fix it.
Once I switched over to a set of higher temp brake pads and I noticed that the pads did not perform well on the street because they really never got up to operating temperature. Did you put pads on your car that were meant for the track? Did you seat your brake pads/rotors after installing them?
Check for air in the lines and check for brake fluid on the rotors. What you are explaining is not normal but I highly doubt that the brake lines have anything to do with the problem. If the brakes got worse after the flush then take the car back so the dealer can fix it.
Once I switched over to a set of higher temp brake pads and I noticed that the pads did not perform well on the street because they really never got up to operating temperature. Did you put pads on your car that were meant for the track? Did you seat your brake pads/rotors after installing them?
Last edited by Spokane5150; 03-27-2012 at 05:31 PM.
03-27-2012, 05:53 PM
#6
Thanks all
First of all thanks for the replies..
I ordered Porsche parts from Suncoast (pads and rotors) so meant Porsche parts when wrote OEM, original equipment manufacture etc... These are not aftermarket.
I added steal lines because they were not all that much money and did/do plan to do some track events and I have never heard of quality steal lines being a bad thing. While I was upgrading the pads, rotors etc and having initial work done figured would have the shop do this as well. I know the stock lines are of high quality, not debating that.
The dealer re-flushed and yes used that process one mentioned about how they bleed the air out of the lines....no longer the manual way etc.
I am going to get the car tomorrow (1.5hrs from home.....) and hoping things are resolved. The tech working on the car has been there 10 years and mentioned he would be in if I wanted to take him out and recreate the problem... hoping I don't have to.
Thanks again for the comments all, much appreciated...
I ordered Porsche parts from Suncoast (pads and rotors) so meant Porsche parts when wrote OEM, original equipment manufacture etc... These are not aftermarket.
I added steal lines because they were not all that much money and did/do plan to do some track events and I have never heard of quality steal lines being a bad thing. While I was upgrading the pads, rotors etc and having initial work done figured would have the shop do this as well. I know the stock lines are of high quality, not debating that.
The dealer re-flushed and yes used that process one mentioned about how they bleed the air out of the lines....no longer the manual way etc.
I am going to get the car tomorrow (1.5hrs from home.....) and hoping things are resolved. The tech working on the car has been there 10 years and mentioned he would be in if I wanted to take him out and recreate the problem... hoping I don't have to.
Thanks again for the comments all, much appreciated...
03-27-2012, 05:53 PM
#7
Rennlist Member
Do the brakes work better after they warm up?
Did you also get the steel lines from Suncoast?
Do you still have the original parts? If you do, can you reinstall those parts?
Did you also get the steel lines from Suncoast?
Do you still have the original parts? If you do, can you reinstall those parts?
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03-27-2012, 10:06 PM
#8
Race Director
Well Mackster beat me to it...either bed in the brakes...but you'll have to do some illegal driving to dot his...Or just put 200 or so city/suburban miles on the car and you'll get that pad to rotor transfer and the brakes will grad better again.
I run into this same feeling every month from switching race and street pads around and new rotors around every 6months depending on how many DE's I do.
I run into this same feeling every month from switching race and street pads around and new rotors around every 6months depending on how many DE's I do.
Last edited by mdrums; 03-28-2012 at 12:19 AM.
03-28-2012, 01:53 PM
#10
thanks.....
"In this case the power bleed system used by the dealer may not be up to the task. Hard to believe though, for this system is used to flush/bleed brake systems that are bone dry, after the brake hardware is replaced.
But assuming the worst, one possible tack would be to do a brake flush/bleed using the old manual method."
Dealer just did this as per your note the manual way and believes it fixed the issue.... I am picking the car up tomorrow and will keep all posted. Thanks again for the replies and thank you for the above tip..... much appreciated....
But assuming the worst, one possible tack would be to do a brake flush/bleed using the old manual method."
Dealer just did this as per your note the manual way and believes it fixed the issue.... I am picking the car up tomorrow and will keep all posted. Thanks again for the replies and thank you for the above tip..... much appreciated....
Couple of things:
Did you perform a brake bedding in after installing the new brake pads/rotors?
OEM is not the same as OE. The new pads/rotors may just not have the same brake performance as the OE pads/rotors.
While you use the term brake fade it is hard to image the brake hardware so crummy as to experience fade from the heating from what is rather mild braking.
Thus, what you may be experiencing is lack of brake boost which requires more pedal effort which can feel like the brakes are fading.
If the boost is down, or if possibly the new steel brake likes are routed/shaped differently there's the possibility a standard Porsche brake fluid flush/bleed will not remove all the air from the system.
In this case the power bleed system used by the dealer may not be up to the task. Hard to believe though, for this system is used to flush/bleed brake systems that are bone dry, after the brake hardware is replaced.
But assuming the worst, one possible tack would be to do a brake flush/bleed using the old manual method.
Now if not done right, this can make things worse, for it can make one believe the bleed is not the problem when in fact it is.
Also be aware it is not a good idea to fully depress the brake pedal all the way down when bleeding the brakes this way for this puts the master cylinder piston into a area of the master cylinder it has probably never been in before. This area can have dirt or corrosion present either of which can damage the piston and its seal with the cylinder.
Sincerely,
Macster.
Did you perform a brake bedding in after installing the new brake pads/rotors?
OEM is not the same as OE. The new pads/rotors may just not have the same brake performance as the OE pads/rotors.
While you use the term brake fade it is hard to image the brake hardware so crummy as to experience fade from the heating from what is rather mild braking.
Thus, what you may be experiencing is lack of brake boost which requires more pedal effort which can feel like the brakes are fading.
If the boost is down, or if possibly the new steel brake likes are routed/shaped differently there's the possibility a standard Porsche brake fluid flush/bleed will not remove all the air from the system.
In this case the power bleed system used by the dealer may not be up to the task. Hard to believe though, for this system is used to flush/bleed brake systems that are bone dry, after the brake hardware is replaced.
But assuming the worst, one possible tack would be to do a brake flush/bleed using the old manual method.
Now if not done right, this can make things worse, for it can make one believe the bleed is not the problem when in fact it is.
Also be aware it is not a good idea to fully depress the brake pedal all the way down when bleeding the brakes this way for this puts the master cylinder piston into a area of the master cylinder it has probably never been in before. This area can have dirt or corrosion present either of which can damage the piston and its seal with the cylinder.
Sincerely,
Macster.
03-28-2012, 02:24 PM
#11
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03-29-2012, 04:00 PM
#13
I got Brakes
All set, such a difference... thanks all for those that replied with help and advice and even spell check
Macster, you nailed it buddy.....thanks again for commenting.
Car runs great and stops well!
Macster, you nailed it buddy.....thanks again for commenting.
Car runs great and stops well!
03-30-2012, 12:06 AM
#14
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You're not describing brake fade. As someone said, street driving is not enough to make the brakes fade. My stock brakes didn't fade on-track until the last few laps of a 20 minute session, in a Texas summer.
Is your pedal firm, but you're not getting good brake bite? That could be bedding. Re-bed your brakes. And make sure your pads have enough surface and are installed correctly.
If your pedal not firm? That could be a shortcoming in the hardware. Brake lines, leaks, or not enough fluid. Make sure you have enough fluid and that every connection, bleeder valve, and cap is tight. You don't describe driving conditions sufficient for a few air bubbles to be an issue.
Is your pedal firm, but you're not getting good brake bite? That could be bedding. Re-bed your brakes. And make sure your pads have enough surface and are installed correctly.
If your pedal not firm? That could be a shortcoming in the hardware. Brake lines, leaks, or not enough fluid. Make sure you have enough fluid and that every connection, bleeder valve, and cap is tight. You don't describe driving conditions sufficient for a few air bubbles to be an issue.
