Originally Posted by clark123456
Are you suggesting the brake pads are causing the rotors to 'warp'?
They are not necessarily the root cause, although when matching pads and rotors you have to take into account that the harder material will cause the softer material to wear away faster.
Lots of things can cause 'warpage'. And deformation of the actual rotor as a unit, what you usually think of when you hear 'warping', isn't always what's happening.
Basically what's going on is something caused the pad not to have an even mating surface with the rotor, leading to uneven transfer of material and uneven contact between the bad and the rotor. Which eventually leads to the pads biting away certain surfaces of the rotor faster than others. Once you're THERE, you're gonna get that vibration in the wheel when braking which makes it feel like the rotor is deformed, when it's actually that something has caused it to wear unevenly to the point where you can feel that sensation in the steering wheel.
If the rotor were actually DEFORMED and that was the only problem, shaving it down would not solve anything as you would end up with a thinner rotor but still the same uneven surface. But the rotor is actually UNEVEVENLY WORN, which means if you shave the top layer of material it will temporarily solve the problem because the mating surface between the pad and rotor becomes even again. Deformation is a cause of the problem, but it usually eventually goes away. When the rotor returns to its normal shape the DEFORMATION issue is replaced by a properly shaped rotor with an unevenly worn surface. If we do a really hard panic stop, the vibration we feel right after is from sudden heat buildup and uneven dissipation, and the resulting temporary deformation of the rotor. If we cool them down gradually all goes back to normal. If we don't, the vibration worsens as the DEFORMATION causes UNEVEN WEAR.
It can happen from rust build-up, hydrostatic shock which causes the rotor to temporarily deform and then not mate properly with the pad, or even just a couple of really hard panic stops where you don't follow up with smoother more gradual braking to cool the rotor down more slowly. Any time that rotor heats up really quickly and doesn't dissipate the heat gradually enough you will have this problem.
I believe part of the problem is whatever materials the manufacturers are using for OEM rotors on heavier trucks nowadays just don't have a good enough heat resistance to stand up to the abuse that the braking system on a 5-6000 pound vehicle will normally see. Which is why it is quite common to hear about low mileage 'warped' rotor issues in every make and model of heavier SUV and pickup while you don't hear about it as much in passenger vehicles. Fords have it, Chevies have it, Toyotas have it, and Dodges DEFINITELY have it. It's also quite common on low mileage vehicles, such as the OP's 07 with 25K. I can occasionally feel some very miniscule vibration on my 09, which was 12K miles in on it in 15 months of ownership and often sits without moving for a few days to a week at a time. In that situation, you have to periodically do some firm braking followed by progressively more gradual stops to break up the corrosion on the brake linings then give the rotors a chance to cool off slowly.
You will also hear stories of brand new vehicles that sat on a lot for a few months, only being driven a few miles, developing these symptoms.
This is why I won't go OEM if it ain't free. If I can get my one goodwill rotor job within those first 12K miles I'll go for it, after that I go aftermarket for pads and rotors and never look back. My experience has been anywhere from 25-30% more pad life and almost non-existent rotor problems with properly chosen aftermarket brake combos.