Thoughts on warping Rotors ?

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I've gone through TWO sets of rotors now in under 15k miles!! :bang:

I purchased my built cruiser with 103k miles on it, and according to the friend I bought it from was running OEM rotors and pads. At about 151k miles, I finally replaced the front brakes with OEM rotors and Terrain Tamer pads. After about 6k miles the rotors were already warped and vibrating, and I didn't have the time and motivation to tackle the same job again, so I took it to my Indy, and he said whoever told me they installed new rotors 6k miles ago was lying to me. Well - I told him 100% they were new, because I installed them myself. Anyways, they proceeded to install new OEM rotors (at 158k miles), but I'm not sure if they changed the pads, because the invoice only says "pads (if necessary)". Presumably, it wasn't necessary, and it's still running Terrain Tamer pads.
I'm now at 165k miles, but the rotors were already feeling warped a couple thousand miles ago. Any idea how these rotors are warping within 5-6k miles? Its happened to two sets now. I've heard good reports on Terrain Tamer pads, so I can't imagine that they are the issue, but they're the only non-OEM part in the brake system. Before I go and replace the brakes AGAIN, I'd like to hear any input on other possible solutions.

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GTV

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My rotors have been feeling a bit warped as well. I am absolutely religious about engine braking and using the brakes as little as necessary so I'm pretty surprised to be experiencing this. Unlike my old first gen Tundra and Sequoia I was expecting the 100 to have more than adequate binders but maybe this is just par for the course for this generation of Toyota trucks. Shame there is no 100 series BBK.
 
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Rotors may not be physically warped, but rather have deposits on them from hot rotors & pads being pressed together at a stop after hard braking.

“Judder”
 

Somebodyelse5

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I believe strongly that warped rotors are a myth.

Exactly what @Ayune said. If you get your brakes super hot and then come to a stop and hold them in one place, you are seeing a localized material and property change, which leads to a difference in friction, subsequently braking force... it feels like it's warped, but they aren't physically warped...

I have yet to see a single runout measurement to support a warped rotor claim. Turning them works because it removes the layer of material that contains that changed area. But it comes back again because of driving behavior.

Don't heat your brakes up and then sit on them.
 

GTV

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I believe strongly that warped rotors are a myth.

Exactly what @Ayune said. If you get your brakes super hot and then come to a stop and hold them in one place, you are seeing a localized material and property change, which leads to a difference in friction, subsequently braking force... it feels like it's warped, but they aren't physically warped...

I have yet to see a single runout measurement to support a warped rotor claim. Turning them works because it removes the layer of material that contains that changed area. But it comes back again because of driving behavior.

Don't heat your brakes up and then sit on them.

Maybe I should put a dial indicator on mine when I get them turned. My old Tundra made me hyper sensitive about getting the brakes hot, it's hard for me to imagine that my driving behavior is the cause of the issue but I've been wrong before.
 

Somebodyelse5

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Maybe I should put a dial indicator on mine when I get them turned. My old Tundra made me hyper sensitive about getting the brakes hot, it's hard for me to imagine that my driving behavior is the cause of the issue but I've been wrong before.

I would, the issue is that most shops turning rotors don't even measure to confirm before they start cutting. I'd be surprised if any of them could actually explain runout to you.

I've noticed considerably less "warp" feeling after replacing my rotors and not stopping completely while hot... that means i put it in neutral or use the hand brake (especially after freeway exits) or just keep them moving slowly.
 
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I've never had a 'warped' rotor. Why? Because even after hard stops I don't let the vehicle stay static. Even a very slow creep at a light will prevent this. It only takes a few inches to move the pad slowly along. As others have said, it's most likely uneven pad material transfer resulting in spots where the μk is higher on the rotor. The change in friction results in the feeling of pulsation. Sometimes a different pad can reduce this, but it's more about driving technique than chasing different brakes.

That said, if you've not tried Hawk LTS they're really quite good on the 100/200. I'd say 30% reduction in pedal effort and really good braking performance. No increase in dust either.
 
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Thanks for the feedback everyone. I’m going to try to have the rotors turned this weekend, since there should be plenty of meat left on them, and swap in a set of Hawk LTS pads, and see how it goes.

I agree on the driving style, and after the first short lived rotor set I was pretty cognizant of how I was braking, but who knows - perhaps it’s all user error. I had a Cayenne with Ceramic brakes, so maybe I just got spoiled. Those things had endless bite!!
 
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For another reference point, my 99LX has 208K miles now.

I replaced my front pads with new OE about 8K miles ago (6 months ago) as previous pads was wearing down. Didn’t replaced the rotor as it seemed fine.

After installing new front OE pads, after couple weeks, I started to hear periodic squeals and sometimes grinding noise when in slow roll at at stop light. The grind noise sounded like it was skipping some part of rotor as it went full revolution…like if rotor was warped.

It was annoying but not causing any performance issue so I let it ride for many months. So, last month, had some time and suspecting it was the pads and I didn’t “break it in” properly and used old existing hardware, I changed out the OE pads with new aftermarket $50 pads with new hardware.

When changing out the pads, I inspected the rotors via feel and visual and it seemed fine. I also properly broke it in after installing the new pads.

It’s been about 3 weeks or so now and I will say the squeal and grinding noise is gone. So, my experience is it’s the pads and properly breaking it in.

Will go back to OE when this pair wears out.

Amazon: never used it before but this is the brand/product.

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Don't rule out the rears either, they seem to wear faster on these trucks than most vehicles. I had what I was convinced was warped front rotor pulsation, but had to replace rear pads anyway so did rear rotors at the same time with all new OEM. That resolved 100% of the issue, no more pulsation/vibration.
 
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Thanks for the feedback everyone. I’m going to try to have the rotors turned this weekend, since there should be plenty of meat left on them, and swap in a set of Hawk LTS pads, and see how it goes.

I agree on the driving style, and after the first short lived rotor set I was pretty cognizant of how I was braking, but who knows - perhaps it’s all user error. I had a Cayenne with Ceramic brakes, so maybe I just got spoiled. Those things had endless bite!!
Is there a reason you don’t just install oem pads?
 
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I have been all through this on my 2003 TLC. It would happen again and again. I used a few different pads and rotors. Akebono, Stoptech, Porterfield, etc. etc. Turned the rotors, bought new rotors. They would be fine for a while and then the pulsation would come back. It was maddening.

Then, I went through a complete front end overhaul about a year ago at 250k or so. New factory calipers, new factory pads and rotors, bearings, new factory UCAs, new LCAs, frame bushings for the LCAs, new drive axles and flanges, etc. etc. Zero issues. None. Brakes are fantastic again. Truck drives as new. Maybe 12-15k on this setup.

I say all that to indicate, I am suspicious that what might have been happening, is that the brake pulsation was not completely the result of the pads/rotors, but that it might have introduced vibrations and minor pulsing that were amplified by bad bushings, etc. Sorry I cannot pinpoint the exact offending item, but that was my experience.

Sorry you don't want to hear that, but that's the way it was for me.

Keep the Cruiser Faith !

R.
 
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I suspect it's the pads as you alluded to. A resurface and OEM pads should be good. Not to be disparaging but some people are just hard on brakes. My service history says rotors were replaced and/or resurfaced three times!! from 110k to 150k - which I thought was insane. This is probably asinine advice but I'll share it anyway. No matter how hard I brake I try to give myself room for 5-10 feet of light braking roll-out (for lack of a better way to describe it) before coming to a complete stop. I suspect hot pad material gets on the rotors when you heat the brakes and come to a complete firm stop.. If any of that makes sense. (it's the full stop on hot brakes that gets em)
 
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I had warped rotors. PO had them on for 150k and they'd been turned three times. I had them turned and did a proper bedding in with new pads and they went back to shuddering within 10k - my feeling is the metallurgy changes some after they get very hot and then cooled quickly (see winter driving the passes in snowy conditions, for example).

Put new OEM rotors and pads on, bedded them in and have been good for the last 40k. We do plenty of mountain passes, but drop overdrive on the shift column and will kick it down a gear and hold a little extra RPM on the long downhill sections. If you ride the brakes they get heat soaked and you can't really get into them in an emergency.

If you aren't bedding the brakes in after they are installed this could be part of it as well.
 

hoser

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I haven't turned my rotors in many years. Turning them reduces material, reducing mass and thus reduces the brake systems ability to absorb and dissipate heat. I do resurface them like in post #13, removing the "rust edge" and "honing" the surface between brake pad changes.

But in my youth, I had 'warped' rotors and was able to turn my own rotors (my friend's family had a auto repair shop) and I remember there to certainly be high and low spots on the rotor. So I'm not able to draw a conclusion on warped rotors vs brake pad build-up. I've since purchased vehicles with higher performance brakes and I've not had any issues... even with many track events. One difference (besides better brakes) is I always bed in new pads by driving 50mph and braking for 20-30 seconds... as in two footing it, both throttle and brake. I keep doing it over and over. I also check the brake rotor temperature via IR gun to look for consistency left to right. Front to rear will be different.
 
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I suspect it's the pads as you alluded to. A resurface and OEM pads should be good. Not to be disparaging but some people are just hard on brakes. My service history says rotors were replaced and/or resurfaced three times!! from 110k to 150k - which I thought was insane. This is probably asinine advice but I'll share it anyway. No matter how hard I brake I try to give myself room for 5-10 feet of light braking roll-out (for lack of a better way to describe it) before coming to a complete stop. I suspect hot pad material gets on the rotors when you heat the brakes and come to a complete firm stop.. If any of that makes sense. (it's the full stop on hot brakes that gets em)
My shop resurfaces rotors for every brake job so I wouldn’t be concerned about that, ideally you want new pads to start with a clean surface. Oem products are designed and tested throughly together and mixing in aftermarket parts often causes issues.

IMO at least for us, it’s not short or hard braking that causes most issues, it’s when people hold the brakes down long descents. I’ve seen plenty of cars with under 20k where we can’t get the rotors in spec after multiple passes due to them being warped. Often, those cars are from one city nearby that is at the bottom of a several mile highway speed descent.
 
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I think there is the possibility as outlined above that issues with bearings and bushes in the suspension are the root cause of it.
If that is in order, I think warpped rotors are rare and mostly due to residue. That is if the rotor isn’t moving in any way vs the caliper.
 

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