I'll bet you folks that are having these issues that 99% of the time it's because of you clamping your pads on your rotors at a stop. So... next time one of you guys has this problem, and you get your rotors replaced, pm me so I can send you shipping for your old "warped" rotors please

Seriously though, often a fix for this is to go through a re-bedding procedure, or like the previous poster said, some really heavy driving. Worst case you can just get the rotors turned. Once you get it fixed though, change your driving habits and stay off those brakes when you can help it. This isn't a fault of the car, but rather the driver, so fix yourself

 

Hmmmm - brand new rotors 'warped' w/ 2-3K miles....$50 shipping - 30 minutes of bedding - .....$profit$

This time I am going to type it in really big red bold underlined letters

Your rotors are NOT warped. You have driven in such a fashion as to create an uneven transfer layer which the pad sees as a big BUMP when it hits it. At high speed this is felt as pulsing in the pedal and steering wheel shimmy. If you take it to the dealer they will go and turn your rotors thus reducing their life. It will fix the problem until you drive the same way again - and the dealer will then turn the rotors yet once again - unless they are under minimum thickness in which case they will sell you rotors for about $750 dollars plus labor.

 

at my ranting

 

You are still clamping the rear brakes which are going to be hot as well. If you are driving "spirited" enough to heat the fronts (while these do see more of the braking force) the rears are still being utilized (heating up) and the same thing can occur to the rear rotors.

At an auto-x event or track event, bring chocks. Do not use the e-brake. At a stop light...you can minimize the impact to fronts (by using the e-brake to hold the car) or try doing a cool down period before stopping....such as making a right turn or jaming into a parking lot for a slow tour around the local wal-mart.

 

Damn i know the rules say somewhere that your not supposed to do that, . Can you find Bigger Font, let alone a brighter color. i though My computer was under alien attack or something. And who made you the ASE certified mechanic? How do you know his rotors aren't warped, you haven't even seen his car? I got an Easy way to fix the prblem, If he is right then you should be able to fix the Pulsation with brake cleaner, spray it on and then wipe the rotor down with a rag.

 

I just wanted to say "Thanks" for all the useful information. After reading through the responses, it makes alot of sense as to whats causing this pulsing. I'm gonna' take EVObrakes advice and rebed the pads again, maybe take some garnet paper to the rotors. I'll also try and start using the e-brake at stop lights etc. Once again: Thanks!

 

Brake cleaner won't work... a tough re-bedding will work... a roloc wheel will work... a lot of sanding down will work. This problem is common, and I'm sure he's right as I would have said the same thing.

 

This is not correct. The parking brake uses a drum brake inside the hat of the rear rotor. It is not possible to leave uneven deposits on the rotor by using the parking brake. One thing that could happen if your brakes are very hot is you could get your parking brake stuck, but that's not very likely and the brake will come loose with a little effort.

-Paul

 

Try down shifting as you are coming to the light, thus not heating up the rotors as much. If you are very good, you won't even get to use the brake as often. And prolonging their life.

Kats

 

He's exactly right, and that's something I didn't mention because I assumed it was common knowledge with respect to our cars. My tip only applies to a car with a drum-in-disc e-brake system as opposed to one that uses the caliper to provide the e-brake function.

 

If there was a bigger-brighter font I would have used it.




Mechanic?? I'm a degreed Mechanical Engineer. And I've been studying brakes for years. 24-7.

I am not - nor will I ever be - a certified mechanic because I'm not that good at it.


Because it is EXTREMELY unlikely if not impossible to generate enough heat w/ OEM pads to distort a 22lb rotor made by Bradi. It may get distorted - or have runout by over-torqeing the wheels lugs - or if some crud is between the hub and rotor face but the car is new so all of it is very unlikely.

??

 

Poor choice. What's worth more, brakes or your engine? Using the engine's compression to decel the car as opposed to a much cheaper wear item like the brake pads and rotors is a bad call. Save the engine decel for when you don't have the brakes to slow down the car.

 

I stand corrected!

 

Ok Yes I was Rude. But Do you know how you Warp Rotors? Rotors warp when they change temperture Rapidly, I.E. Your are Brake Either Hard or just have been going down a hil or been driving in stop and go for a while, your rotors are hot and then you hit a puddle and your rotors get doused in water and cool rapidly. Thats why you not supposed to wash your car after you just drove it, let it sit an cool for a while, EXPECIALY since evos have that hood vent, if you have an aftermarket maninifold and its nice and toastly i don't think putting water on it will be smart, I have never read anything bad happening but i just wouldn't do it.

 

Downshifting doesn't damage your engine, as long as your note going from highway speeds to second gear. Ohh yeah I don't think you can Downshift into First, at least i don't.