larrychery

I searched around a bit on the forum and didn't find anyone else with this issue, but I apologize in advance if someone else has experienced this. Feel free to link me if so!

I have a 2013 RX350 2WD and one of the brake rotors keeps re-warping after around 1000 miles. I had all the brakes done about 10k miles ago (local mechanic that only works on Toyota/Lexus, he's very good/knowledgeable), and recently this one particular rotor keeps getting warped. I took it back to my mechanic and he turned the rotor, shaking vibration went away immediately when braking, but returned in full force about 1000 miles later. This was not the result of a hard brake or hard stop - just normal driving conditions.

Any ideas what could be causing this? It does not seem that the caliper is sticking nor is there any abnormal noise coming when accelerating or braking. The car moves freely and all wheels move freely when jacked up.

Aegean

Swap the rotors left to right and see again in a couple of thousand miles what happens.

larrychery

I will give this a shot and see what happens / report back. Thanks!

Clutchless

Do you only do soft and slow braking? If so you are probably getting pad material building up on the rotors, not actual warpage. The pad material deposits unevenly on the rotor.

Did they tell you to bed in the brake pads and how to do it? Google it.
To bed in the brakes, the brakes need to be hot enough to transfer friction material. The usual procedure is brake moderately from high speed a few times. The important factor is to not come to a complete stop - always keep the car moving so the rotors are ventilated and so the pad material does not imprint on the rotor. Refer to the brake pad's manufacturer for specific instructions on pad bed-in.

If you feel that again try a few hard and fast stops to try and scrape that crap off the rotor.

Here is a discussion of this problem on a BMW forum. https://www.m3post.com/forums/showthread.php?t=1384226

Here are more discussions of pad deposits on rotors.
https://trade.mechanic.com.au/news/s...d-brake-rotors
https://blog.fcpeuro.com/warped-brak...-internet-myth

Or maybe that caliper needs to be replaced.

smknkeyz

grease the slide pins on the calipers while you're at it! Those things seem to always cause issues!

NoReligion

High speed brake vibration is caused by a thickness variation in the rotor as it spins. My understanding is that rotors do not "warp" like a potato chip, although this is the term that everyone uses, but it is technically incorrect. My understanding is that there are two main reasons rotors develop a thickness variation after a relatively short period of use. First is improper installation of new rotors with an unacceptable level of lateral run out. For example, the hub was not properly clean leaving some debris between the hub and rotor results in a small wobble. Initially the brakes feel fine. However, over time the pads will start wearing down the high spots on each side of the rotor as it wobbles. Lateral run out over 1/1000 inch can lead to thickness variations. The only way to make sure the rotor is installed properly is to check them with a dial gauge. To properly check for lateral run out without the tire mounted you must use conical washers and tighten each lug nut evenly with a torque wrench, then use a dial gauge. Most shops do not take the time to check for lateral runout after they install rotors. I think in some rare cases, a rotor can come from the factory with unacceptably high lateral run out, but you will also see this with the dial gauge after the install. The second common reason for developing thickness variations is not tightening lug nuts using the star pattern and not applying even torque to all nuts. It is critical to use a torque stick extension to limit the torque of impact wrenches AND to check each lug nut with a manual torque wrench.

Elofeye

Did you find a solution?

larrychery

I ended up having a independent shop (that I trust and have used for all of my Toyota / Lexus maintenance) replace the rotors (not resurface) and pads on both sides. It's been over 1k miles since and there hasn't been an issue. I'm guessing the resurface of the rotors previously didn't work. The shop owner mentioned that they were beyond resurfacing at this point anyways.

carguy75

Sound like you may have had a bad rotor from the factory that was warped or deformed that was not easy to see by the naked eye.

Note: Always check your lug nuts to make sure that they were properly torqued after the wheels are removed. Sometimes rotors warp due to the lug nuts not all being torqued to the same ft/lbs against the hub. Some service techs in repair shops just zip down the wheel nuts with an air impact tool without checking the torque values which can be different with each wheel nut and causes the rotor not to sit perfectly flush against the hub; which allows the rotor to warp due to deforming it shape after it heat and cools during braking over time.

bearcav

isn't there also a TSB about RX's destroying rotors? The "fix" was to cut back some plastic flap to get more airflow to the brakes...can't find the article.

I had the same issue, eventually decided to use EBC rotors and haven't had an issue in 30k miles.

Clutchless

I recall such a TSB for the Toyota Sienna as I have one, and trimmed the plastic myself, but not for the RX.
The lack of air flow caused the rotors to overheat and warp and wrecked the brake pads. Toyota called for the plastic flap to be trimmed and installation of new rotors and better high temperature resistant brake pads.

NHTSA has a database of recalls and complaints for any vehicle. Here is a link for the 2010 RX350. I think the TSBs are listed under Manufacturer Communications. There is a lot to look at and that is just for one model year.
​​​​​​https://www.nhtsa.gov/vehicle/2010/L.../FWD%25252FAWD

salimshah

I have put close to a million miles on various Lexus vehicles and never had a rotor warping issue. Granted it is a ONE person experience but I would not blow it off as it has been on various Lexus vehicles. All OEM rotors and pads in good working condition [brake fluid serviced per spec].

Here is my magic to have no issues with brakes.

1. Control the need for braking by throttle control and anticipating the need. This reduces stress and use [there are other benefits too]
2. For slowing down use the brakes in apply and release pattern. I am not saying Stomping and letting go, but gentle brake and let off. This reduces heat buildup.My family really got annoyed riding with me. I have to change this for the hybrid where I keep constant low pedal force to regen while not scraping pads. [The only negative which I can attribute to it was brake module failure as I over switched it]
3. My lug nuts were always torqued to spec. [this issue is debatable with the pass-through-bolt rotor, but still no harm]
4. Replacing brake pads at the right time. I replace as soon as the scallop at the leading edge of the pad is gone and not wait till the pad reaches factory minimum.
5. Do not carry extra weight in the vehicle. Has other benefits but the braking effort is reduced.

Based on the above I have never had the need to have the rotors turned. Shops typically turn the rotors when they perform a brake job [this is done to have no customer complaints after the brake job]. By reducing the metal thickness, the rotor is more prone to be warped.

I hope the above helps.

Salim