Brake pulse--your opinion on what all to replace??
04-18-2018, 08:21 PM
#1
Racer
Thread Starter
Brake pulse--your opinion on what all to replace??
I have a 2010 base with 71xxx on the clock. Looking forward to our annual Tail of the Dragon trip in the mountains of eastern NC where several days of extra spirited driving will occur. 
Getting car prepared, and have recently noticed a very subtle vibration in the car when on the brakes hard. I replaced front pads only a year and 10k miles ago. So....I don't want to cheap out and not properly remedy; but don't want to waste parts/money either. I intend to replace all 4 70k mile rotors. Do I also need to replace the front pads? Keep in mind they only have a year and 10k miles on them (and are $100...). I will be looking at rear pads later to inspect wear. What are your opinions on replacing rotors without replacing pads? Will old pads quickly wear to match new rotor surface or do I risk grooves etc in old pads eating into and damaging new rotors? Any performance concerns? I'm probably overthinking this; but with mountains, heavy braking, and a passenger I want to feel confident the car is operating properly. Also don't want to throw a wad of unnecessary $$ at it if makes no difference... Educate me!
Getting car prepared, and have recently noticed a very subtle vibration in the car when on the brakes hard. I replaced front pads only a year and 10k miles ago. So....I don't want to cheap out and not properly remedy; but don't want to waste parts/money either. I intend to replace all 4 70k mile rotors. Do I also need to replace the front pads? Keep in mind they only have a year and 10k miles on them (and are $100...). I will be looking at rear pads later to inspect wear. What are your opinions on replacing rotors without replacing pads? Will old pads quickly wear to match new rotor surface or do I risk grooves etc in old pads eating into and damaging new rotors? Any performance concerns? I'm probably overthinking this; but with mountains, heavy braking, and a passenger I want to feel confident the car is operating properly. Also don't want to throw a wad of unnecessary $$ at it if makes no difference... Educate me!
Last edited by Wampa; 04-18-2018 at 08:23 PM. Reason: spelling
04-18-2018, 09:18 PM
#2
Instructor
Opinions may vary, but I would pull front pads and inspect the surface of both. If relatively smooth then I would install on new rotors. And your rotors are probably what you are feeling.
04-18-2018, 09:24 PM
#3
Race Car Tech
You can only change the rotors and keep the hardly worn pads. I would suspect that the pads would have at least 75% life remaining after only 10K miles, but I guess it depends on the use (racing, hard braking, etc.)
If you decide to keep the old pads on, you will have some reduced braking power until your old brake pads wear in the new rotors so the full pads makes contact with the full new rotors.
From that point on, you will be back to enjoying full braking power.
It's your decision.
If you decide to keep the old pads on, you will have some reduced braking power until your old brake pads wear in the new rotors so the full pads makes contact with the full new rotors.
From that point on, you will be back to enjoying full braking power.
It's your decision.
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Wampa (04-18-2018)
04-18-2018, 10:29 PM
#4
Racer
Thread Starter
Thanks for the input guys! After stressing it, I decided the expense is worth the piece of mind and ordered all new pads and rotors for all 4. I'm comfortable doing the labor so can rationalize the cost away lol. Any other opinions are still welcome as I'm sure some on here are much more experienced/knowledgeable on the subject and I could learn from your input!
04-19-2018, 02:05 PM
#5
Instructor
The pulsation you felt at braking is due to your warped rotor(s) & your only year old front pads s/b fine so what you can do is put them back on when you replaced the rotors then go for a test drive. If the pulsation still there then you can swap them out w/ the new ones. Return or save the new pads for later.
04-19-2018, 02:48 PM
#6
Melting Slicks
Sounds like you've already got a plan but my 2 cents is that the pads can't cause the pulsing. It's almost always warped rotors but there is a small chance it's a bad wheel bearing.
04-19-2018, 05:24 PM
#8
Supporting Vendor
Pulsing brakes is most often a result of overheated pads that deposit on the rotor leading to uneven friction i.e. the pulsing.
You can clean the rotors or often re-bed if it's not too bad but sometimes it can require turning to make it go away.
The pad compound and driving style are what to balance with pad selection.
Ken
You can clean the rotors or often re-bed if it's not too bad but sometimes it can require turning to make it go away.
The pad compound and driving style are what to balance with pad selection.
Ken
04-19-2018, 05:57 PM
#9
Burning Brakes
Hello Friends,
What many times happens is the rotor gets heated up during spirited driving and then you come to a stop and hold your foot on the brake pedal and some of the brake pad material is transferred to the rotor creating a sticky spot. Then when you brake you feel the pulsating that feels like a warped rotor but is simply a contaminated rotor.
I use a vibrating sander with 80 grit on my rotors to clean them up when installing a new set of pads.
Now I have a ZR1 so the vibrating sander is out!
Good Luck,
Douglas in Green Bay
04-20-2018, 10:53 PM
#11
Stuck caliper piston?
Your car is 8 years old. It's a little early to have symptoms of a gummed up and stuck caliper piston that has caused the pad to drag against, overheat, and warp the rotor. But, that is possible. It doesn't take a lot of dragging for this to happen, and it can be very subtle to the extent that you would never notice it happening.