I was chatting with someone about how my SUV seems to warp rotors all the time. He said, that, for years he would buy high heat paint, and paint inside the rotors.

I'm concerned thinking that part is for heat dispersion and wouldn't that actually warp them? He recons that the heat dispersion is affected when the inside rusts and swears that he has never had a warped disk and that it is a good thing to do.

Is this a good idea or a bad idea?

  • The bigger question here is, Are they actually warped? ... A lot of rotors which feel as though they are warped were actually not bedded (or broken-in) properly. If brake friction material is lumped onto the brake rotor without the rotor being properly bedded, it can feel as though the rotor is warped (you'll get pulsation through the brake pedal and the vehicle will jerk rhythmically). If the rotors are properly cleaned and then bedded properly afterwards, the rotor will be found to be completely usable. – Pᴀᴜʟsᴛᴇʀ2 Jun 12 '17 at 17:45
  • I did use a guage on the two back rotors. One was 12 thousandths and the other 13 thousandths. However I did not remove, clean and re-seat. I did clean before putting new rotors. Measured that back axel was 2 thousandths and with the rotor I got 3 thousandths and brakes feel smooth. It is possible that all prior brake jobs were just pull off, put on, with no cleanup I suppose. – Chris Jun 12 '17 at 18:12
  • There is so much that plays a part in this, beyond what Paulster2 has stated. Comparison of your vehicle to your friend's is not valid unless they are identical. Please define how your "SUV seems to warp rotors all the time". Does that mean 30 miles? 3,000 miles? Also, what do your measurements mean in your comment? Are you comparing left and right rotors? Warping has to do with the surface of a rotor no longer being true. Lastly, I have found that some "made in China" replacement rotors are not made to OEM standards and will warp when over torqued. Are you using good rotors? – CharlieRB Jun 12 '17 at 18:58
  • Within a year I will get the pulsation in the brake peddle. The measurements were taken by a magnet gauge which allows you to measure warpage. Spec is supposed to be 3x1000th of an inch or less, both my rear were over 12x1000th of an inch. I make sure to torq my wheels now down to 100ftlb as required for my vehicle. Previous rotors were: NAPA premium, followed by Mazda genuine. But don't know past. So started clean 4xNew NAPA Prem Rotor+Pads+correct Torque. I am curious about this paint thing. – Chris Jun 12 '17 at 21:18
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    I think you need to forget about the paint thing for now and find out what's causing the problem. Brake rotors shouldn't "warp" in this way. Two things I would start out with myself are 1. Check calipers thoroughly - is there a problem with the brackets that mount the calipers or are the guide pins stuck and 2. Check and clean the surface that the rotors contact - is there any rust or other build up that's preventing the rotor itself from sitting true. – Tedwin Jun 13 '17 at 5:15

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