Front brake rotors that won't warp

Joined
Jul 21, 2020
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I'm having a hellauva problem with warped front rotors. New rotors warp within about 2 months. Car is an 04 Subie Outback, it's slow AF and not driven aggressively, but the rotors warp after some knucklehead cuts in front of me and I have to get on the brakes hard to avoid hitting him. I have put on good quality stuff and it still warps while Autozone rotors and pads do not warp on my wife's Forester and Bendix pads and rotors last forever on my old IROC Camaro which does get driven more aggressively. So what do I need for my Subie that won't warp in 2 months? Thanks!
 
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We had a 06 Mazda3(daughters car) like that. She couldn’t keep rotors on the car, I don’t care what we used.
Her next car; 15 Civic couldn’t kill the OE. Same driving conditions.
 
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Are the hubs and everything free of rust, sitting correctly, are you using the screws that hold the rotor on hub? Also make sure there's nothing sticking the pins are good and slide freely the calipers are not locked up, correct brake fluid if it hasn't been changed in a couple years change it out things like that.
 
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Most likely it's a sticking pins issue or rust has formed under the pads mounting clips on the caliper which stops the pads from moving freely. Check that the pins have good grease and that the rubber boots haven't s swollen up.
 

Bigger John

Thread starter
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Jul 21, 2020
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Most likely it's a sticking pins issue or rust has formed under the pads mounting clips on the caliper which stops the pads from moving freely. Check that the pins have good grease and that the rubber boots haven't s swollen up.
New pins. Greased them myself.
 
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You could try not stopping with hot brakes, but instead, moving forward slowly to keep the pads from sitting on one spot. It may help a little. I absolutely do not claim this is the answer, only that some people report better results.

Sometimes only one rotor warps, and we replace both thinking they are both bad. I have an F150 that absolutely destroys rotors every time after a spirited drive on the Blue Ridge Parkway. And there are no stops involved. Just repeated hard braking. They get worse and worse as they heat up. I end up purchasing aftermarket ones when I can't stand it anymore. The Brembo replacements seem to be fairly good.
 
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Check what everyone is saying up.
Better rotors? Pagid, ATE, Brembo, EBC, Hawk, Akebono, Textar.
If you can source Brembo for decent price, get it. But make sure calipers are ok.
 
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I should also add, a significant percentage of the racers I know use the absolute cheapest rotors they can find, without issue.
I use ATE on track and street. I just change pads.
But I wouldn’t use just anything. Yes, ATE, Pagid, Textar, Brembo. But not cheapest stuff from RockAuto or whatever.
 
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I would question the calipers. Are they hanging and causing the rotors to heat?
I agree with this but, I can't answer for the OP.
In our Mazda3 case, the calipers were perfect, never handing up and brakes were strong/niiiice!
And I have to also say that the pads lasted foreveeeeeeer but just couldn't keep rotors on the front(rear were ok). I think its more vehicle specific. The rotor msg's make rotors to the cars spec. For example, I had a car, that even the cheap rotors lasted quite long(as good as OE or better). So, I never had to concern myself when using the cheapies. But we've had other cars that even ate up BREMBO, CENTRIC etc. It didn't matter! :unsure:
 
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I agree with most what's been said. When rotors warp it's rarely the rotors' fault.
IF they're even actually warped at all. Maybe there's some pad compound residue
left on the rotor's surface from stopping with (over)heated brake pads and the
resulting uneven brake force is amplified by play in old wheel bearings, ball joints
and steering rods. Sticky calipers (pads, pins and pistons), worn-out suspension,
unevenly and overtorquening lug nuts or inappropriate (ab)use - all this and some
more is playing a role.
Personally I prefer using either Brembo or OE (Porsche) rotors, but any decent rotor
should work in normal use.
.
 
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Jun 14, 2011
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.
I agree with most what's been said. When rotors warp it's rarely the rotors' fault.
IF they're even actually warped at all. Maybe there's some pad compound residue
left on the rotor's surface from stopping with (over)heated brake pads and the
resulting uneven brake force is amplified by play in old wheel bearings, ball joints
and steering rods. Sticky calipers (pads, pins and pistons), worn-out suspension,
unevenly and overtorquening lug nuts or inappropriate (ab)use - all this and some
more is playing a role.
Personally I prefer using either Brembo or OE (Porsche) rotors, but any decent rotor
should work in normal use.
.
^^^This
Are you sure that the rotors are actually warping? The number one reason for brake vibration is uneven brake pad deposits. The fact that your problem is occuring so soon after replacing the pads and rotors points to not having bed them in properly. Incorrectly bedded-in pads can leave deposits and uneven rotor surfaces when the brake pedal is used. These uneven pad deposits can lead to pad build up over time in those areas. As the material builds up, the thickness of the rotor in that section increases and the vibrations become more apparent. The quality of the brake pads themselves play a part here.

The important thing is that, during the bedding-in process, you should not come to a complete stop after hard braking (unless you HAVE to). This will transfer a large amount of friction material to one spot on the rotor. This is what will cause vibration.
 
Last edited:
Joined
Jun 8, 2021
Messages
221
Location
Columbus, OH
I'm having a hellauva problem with warped front rotors. New rotors warp within about 2 months. Car is an 04 Subie Outback, it's slow AF and not driven aggressively, but the rotors warp after some knucklehead cuts in front of me and I have to get on the brakes hard to avoid hitting him. I have put on good quality stuff and it still warps while Autozone rotors and pads do not warp on my wife's Forester and Bendix pads and rotors last forever on my old IROC Camaro which does get driven more aggressively. So what do I need for my Subie that won't warp in 2 months? Thanks!
No such thing. All rotors warp. Id just out a set of cheapie Auto Zones on it and make sure that you dont overtorque the wheel studs.
 
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Aug 28, 2017
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near Cincinnati, OH
I'd try ceramic pads if you haven't already, agree with others that it's as likely, pad deposits on the rotors for it to semi-consistently continue happening, or as someone else mentioned, you have rusted slide rails or pins so uneven contact.
 
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