Do I need to replace rotors when replacing brake pads
03-23-2019, 10:23 PM
#1
Do I need to replace rotors when replacing brake pads
I am sure these questions have been presented somewhere before on this forum, but I can't seem to find the thread. I recently went to my GM dealership to have some normal maintenance done, when I was told that my brakes were getting very close to needing replacement. I was actually not surprised by that (not being sarcastic). However, what I was surprised by was when they told me I should also replace my rotors, because of potential warping and braking uneveness. I have already decided to go with Carbotech 1521 ceramic brake pads all around. the questions I have are the following: 1) is it really necessary to replace the rotors? 2) If so, what brand would be recommended with the Carbotech 1521 brake pads and 3) Do I need to go with Ceramic Rotors if I am going to Ceramic brake pads? Any other helpful information is also appreciated. Thanks for the help!
03-23-2019, 11:37 PM
#2
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First, there is no reason why you need to replace the rotors just because you change the pads. Are you getting any thumping? Did they tell you the rotors were nearing their minimum thickness spec? If no then there is nothing wrong with your rotors.
If you choose a different brand of pads there may be a short period of time where the brakes won't work as well since they have to build up their own transfer layer on the rotor before they reach their best performance level. That means scrapping off the old pad's layer and then laying down their own layer. They need to do this with new rotors as well. This can usually be cleared up by taking the car and doing a brake burnishing run (see OM).
If you switch to 1521s it will take a day or so for them to break in to the old rotors. You don't need ceramic rotors if you use those ceramic pads. They are made for iron rotors. Besides the stock ceramic rotors will not fit on your car. You need different calipers because the ceramic rotors are so much larger in diameter.
Bill
If you choose a different brand of pads there may be a short period of time where the brakes won't work as well since they have to build up their own transfer layer on the rotor before they reach their best performance level. That means scrapping off the old pad's layer and then laying down their own layer. They need to do this with new rotors as well. This can usually be cleared up by taking the car and doing a brake burnishing run (see OM).
If you switch to 1521s it will take a day or so for them to break in to the old rotors. You don't need ceramic rotors if you use those ceramic pads. They are made for iron rotors. Besides the stock ceramic rotors will not fit on your car. You need different calipers because the ceramic rotors are so much larger in diameter.
Bill
03-24-2019, 10:59 AM
#4
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St. Jude Donor '11,'13
I am sure these questions have been presented somewhere before on this forum, but I can't seem to find the thread. I recently went to my GM dealership to have some normal maintenance done, when I was told that my brakes were getting very close to needing replacement. I was actually not surprised by that (not being sarcastic). However, what I was surprised by was when they told me I should also replace my rotors, because of potential warping and braking uneveness. I have already decided to go with Carbotech 1521 ceramic brake pads all around. the questions I have are the following: 1) is it really necessary to replace the rotors? 2) If so, what brand would be recommended with the Carbotech 1521 brake pads and 3) Do I need to go with Ceramic Rotors if I am going to Ceramic brake pads? Any other helpful information is also appreciated. Thanks for the help!
__________________
Adam Adelstein
Amp’D Autosport.com
Internet's largest retailer of Carbotech Performance Brake Pads.
PH:216-780-8825.
Email: sales@ampdautosport.com
Web Site & Direct ordering http://ampdautosport.com/
All major CC and Pay Pal accepted.
Check out Promo code:z28
Adam Adelstein
Amp’D Autosport.com
Internet's largest retailer of Carbotech Performance Brake Pads.
PH:216-780-8825.
Email: sales@ampdautosport.com
Web Site & Direct ordering http://ampdautosport.com/
All major CC and Pay Pal accepted.
Check out Promo code:z28
03-24-2019, 09:24 PM
#6
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St. Jude Donor '11-'12-'13, '16-'17-'18
Had over 52K miles on my Z51 OEM pads when I sold it last August and they still have a ton of pad left (daily driver too)
03-24-2019, 09:30 PM
#7
Hi Alan -
When you apply moderate pressure to the brakes, do you feel a pulsation or does the steering wheel shake until the car stops? If so, rotors at a minimum need to be turned. These days, new rotors on the performance aftermarket are plentiful for these cars and relatively inexpensive. The biggest PITA will be removing the calipers and that's not too onerous; it will make pad replacement and piston retraction that much easier.
If no steering wheel shaking or pulsating on the brake pedal, you're rotors are most likely A-ok. Pads and be done. Carbotech 1521 is a solid choice. Ben at WeaponX has them shipped for ~$439.
You might also want to consider a brake fluid flush if 2-3yrs of age.
Be safe!
When you apply moderate pressure to the brakes, do you feel a pulsation or does the steering wheel shake until the car stops? If so, rotors at a minimum need to be turned. These days, new rotors on the performance aftermarket are plentiful for these cars and relatively inexpensive. The biggest PITA will be removing the calipers and that's not too onerous; it will make pad replacement and piston retraction that much easier.
If no steering wheel shaking or pulsating on the brake pedal, you're rotors are most likely A-ok. Pads and be done. Carbotech 1521 is a solid choice. Ben at WeaponX has them shipped for ~$439.
You might also want to consider a brake fluid flush if 2-3yrs of age.
Be safe!
03-25-2019, 06:01 AM
#8
I listened for pulsating and the steering wheel shake and there was none, which leads me to believe that the rotors are fine. I am going to take the car into a mechanic I trust to have them take a look. If they say the rotors are fine, I will simply replace the pads and move on.
03-28-2019, 10:49 AM
#9
Safety Car
You just need to check the rotors to see that they are fine.Then just change the padsI have driven over 100k in most of my
cars and still had life on the pads.I don't use brakes much.I downshift all the time and use rev match
cars and still had life on the pads.I don't use brakes much.I downshift all the time and use rev match
03-29-2019, 01:08 AM
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St. Jude Donor '13
Hi Alan -
When you apply moderate pressure to the brakes, do you feel a pulsation or does the steering wheel shake until the car stops? If so, rotors at a minimum need to be turned. These days, new rotors on the performance aftermarket are plentiful for these cars and relatively inexpensive. The biggest PITA will be removing the calipers and that's not too onerous; it will make pad replacement and piston retraction that much easier.
If no steering wheel shaking or pulsating on the brake pedal, you're rotors are most likely A-ok. Pads and be done. Carbotech 1521 is a solid choice. Ben at WeaponX has them shipped for ~$439.
You might also want to consider a brake fluid flush if 2-3yrs of age.
Be safe!
When you apply moderate pressure to the brakes, do you feel a pulsation or does the steering wheel shake until the car stops? If so, rotors at a minimum need to be turned. These days, new rotors on the performance aftermarket are plentiful for these cars and relatively inexpensive. The biggest PITA will be removing the calipers and that's not too onerous; it will make pad replacement and piston retraction that much easier.
If no steering wheel shaking or pulsating on the brake pedal, you're rotors are most likely A-ok. Pads and be done. Carbotech 1521 is a solid choice. Ben at WeaponX has them shipped for ~$439.
You might also want to consider a brake fluid flush if 2-3yrs of age.
Be safe!
I've noticed almost no relationship between pulsing and thickness. I've had brakes that pulsed with only 10k easy street miles on the car, and rotors worn below minimum spec that were still running smoothly.
