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Discussion Starter · #1 ·
I haven't taken the wheels off yet to see what one(s) it is but I'm 87% certain I am dealing with warped rotors and that it is the front left. Would I need to replace all my rotors or just the one? Thank you in advance I really do appreciate it.
 

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They should be replaced in pairs same with the pads which should be replaced along with the rotors.
 

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Discussion Starter · #5 ·
I think mine might be warped as well. Only 43k miles. The car is pulsating a little when I'm braking at highway speeds
on mine I only really notice it when the brakes would be starting to warm up and I get a vibration, I can feel the pedal push back at me and if I am braking at low speeds I can feel a bump in the pedal when it gets to the spot
 

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on mine I only really notice it when the brakes would be starting to warm up and I get a vibration, I can feel the pedal push back at me and if I am braking at low speeds I can feel a bump in the pedal when it gets to the spot
Are you doing the brakes yourself? It's not that much to buy new rotors, unless they are high performance.
 

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Discussion Starter · #11 ·
I would check R1 Concepts out they are a vendor on this forum.
went over there and yeah they are cheaper AND I can get drilled and slotted so it doesn't happen again, off chance do you now if the geomet series comes with pads or do I but them separate, no problem with buying them but the video said the package comes with ceramic brakes
 

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went over there and yeah they are cheaper AND I can get drilled and slotted so it doesn't happen again, off chance do you now if the geomet series comes with pads or do I but them separate, no problem with buying them but the video said the package comes with ceramic brakes
I don't know if the pads come with the kits. But I have use the eline series before and really liked them.
 

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went over there and yeah they are cheaper AND I can get drilled and slotted so it doesn't happen again, off chance do you now if the geomet series comes with pads or do I but them separate, no problem with buying them but the video said the package comes with ceramic brakes
Drilled/slotted does not prevent warped rotors. If the rotors were actually warped. This can only be verified by checking the rotor for axial/radial run out with a dial indicator.

If a rotor truly warped the most likely culprit is the rotor was not fully/properly stress relieved. With some cast iron parts the raw castings are left to stress relieve over time on their own. This can be speeded up, after a fashion, by putting the castings outside to experience the day to day temperature changes. My info this can take a year. Mechanical stress relieving can also be accomplished by subjecting the rotors to time on a shaker table provided this does not risk rotor damage which may render the raw rotor casings unsuitable for further processing.

Or the castings can be heated up to some suitable temperature then left to slowly cool which releases stress.

After the above there can still be some residual stresses present and they are "released" by the machining of the rotor. The casting "skin" is removed which should have any residual stress released then a clean up/finish cut is taken to bring the rotor to size and remove any run out arising from the previous release of stress.

The intended result is fully stress relieved rotor machined to the correct shape and size and with the desired finishes. 'course, with the number of rotors produced there will be exceptions. And one of your car's rotors may have been an exception.
 

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Discussion Starter · #14 ·
Drilled/slotted does not prevent warped rotors. If the rotors were actually warped. This can only be verified by checking the rotor for axial/radial run out with a dial indicator.

If a rotor truly warped the most likely culprit is the rotor was not fully/properly stress relieved. With some cast iron parts the raw castings are left to stress relieve over time on their own. This can be speeded up, after a fashion, by putting the castings outside to experience the day to day temperature changes. My info this can take a year. Mechanical stress relieving can also be accomplished by subjecting the rotors to time on a shaker table provided this does not risk rotor damage which may render the raw rotor casings unsuitable for further processing.

Or the castings can be heated up to some suitable temperature then left to slowly cool which releases stress.

After the above there can still be some residual stresses present and they are "released" by the machining of the rotor. The casting "skin" is removed which should have any residual stress released then a clean up/finish cut is taken to bring the rotor to size and remove any run out arising from the previous release of stress.

The intended result is fully stress relieved rotor machined to the correct shape and size and with the desired finishes. 'course, with the number of rotors produced there will be exceptions. And one of your car's rotors may have been an exception.
I understand I cannot completely prevent them but isn't excessive heat one of the causes of a warped rotors?
 

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I understand I cannot completely prevent them but isn't excessive heat one of the causes of a warped rotors?
yup and also over torqing them as in running the lugs on with a impact and not using a torque wrench
 

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I think mine might be warped as well. Only 43k miles. The car is pulsating a little when I'm braking at highway speeds
Hi frankp,
We certainly understand why this may be concerning. We kindly recommend having your dealer inspect this concern for you as they are in the best position to assist. If you do work with your dealer, we would be more than happy to provide you with additional support.
Rob
DodgeCares
 

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I understand I cannot completely prevent them but isn't excessive heat one of the causes of a warped rotors?
Excessive heat can lead to rotor (or pad) degradation. Rotors turn "blue" and can develop hard spots. Or heat cracks can appear. Pads can begin to disintegrate from excessive heat.

Drilled, slotted, and certainly ventilated rotors can limit heat build up which prolongs the brake hardware life and can improve braking action under extreme operating conditions.

Warping arises from the release of internal stresses which cause the part -- in this case the rotor -- to deform. The rotor can develop as best I can describe it a potato chip shape. While the rotor faces are still parallel to each other the rotor has linear runout. A dial indicator placed against the face of the rotor and the rotor turned would indicate some (probably considerable well on the order of at least several thousandths of an inch) of movement.

A indicator directly opposite would indicate the same movement but of course in the same direction. The rotor surfaces are parallel they just no longer run true.

If the rotor retains some internal stresses just normal use with the normal heating and cooling can result in these stresses being released which can then cause the rotor to take on that potato chip shape I mentioned above.

Might mention there is another condition that can be mistaken for a warped rotor. A warped rotor to be confirmed needs to be checked for runout. If it has some, more than allowed by the factory, then it is warped although incorrect mounting of the rotor can result in runout.

What can happen under some circumstances is brake pad material can be transferred from the pad to the rotor face. This happened to one of my cars.

Briefly, I washed the car but didn't drive it afterwards. The car sat at least overnight and maybe longer. When I went to drive the car the brakes were "frozen" rusted and let go with a pop.

All was well but I didn't have the presence of mind to use the brakes any and there was no need to use the brakes until some mile or so down the road I had to perform an emergency braking action to avoid a car that ran a red light. I brought my car to a safe stop. I left the brake pedal depressed.

Afterwards I noticed with light braking there was a pulsing in the pedal. The hard braking action generated enough heat and combined with the load of rust dust on the working surface of the pad this resulted in some transfer of material from the pad to the rotor. Afterwards the area the pad(s) had been in contact with the rotor after the stop the rotor surface in that area had a different coefficient of friction.

Rotor surfacing or replacement were my only alternatives. But I found the pulsing was only present under light braking so I adopted a slightly more aggressive braking style and the pulsing was not a problem and I really didn't think about it until I put the car up for sale with nearly 150K miles on it -- and with the original brakes -- and the buyer who of course had a light braking style of driving noticed the pulsing.
 
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