Warped Rotors

[marcuzzo85]

whats up guys...my rotors are massively warped and its time for a change...what are the better sets i should be looking for? and i need pads as well...help would be greatly appreciated, thanks.

[zmz3]

no need to panic, there's a lot of discussion on rotors and brake pads.

It seems that many of the members here are opting for the Mazda Original Rotors and HAWK HPS brake pads.

OR you could always run original everything,stock rotors and pads from Mazda.

My recommendation, to save a lot of cash, is to buy parts from Mazda of Toronto (lowest price usually) or any Mazda dealership then take it to Jimmy at Street Performance for installation, He usually charges $130 for front and rear brake pads/rotors installation.

If you are interested in the HAWK HPS pads, i'd suggest you look at a sponsor like nextmod.

Street performance is located around Woodbine and Steeles in Markham.

Good luck

[cwp_sedan]

That just about sums it up in a nutshell!

:thumbsup

[Migeta22]

hey Marcuzzo, how do you know your rotors are warped? cause my steering wheel shakes when braking at high speed and I've been wondering if its my rotors.

[Punkrockjohn]

hey Marcuzzo, how do you know your rotors are warped? cause my steering wheel shakes when braking at high speed and I've been wondering if its my rotors.

I had the same problem a couple months ago, they are definitely warped. I always wondered why this happens so often.

[Migeta22]

I had the same problem a couple months ago, they are definitely warped. I always wondered why this happens so often.

do you happen to know the cause of the warp? and maybe how to prevent it?

[Egierda]

Brembo blanks or Stoptech/Powerslot rotors are solid aftermarket options. As mentioned previously, Hawk HPS or HP Plus pads are great pad choices.

[MajesticBlueNTO]

do you happen to know the cause of the warp? and maybe how to prevent it?

the most common cause of warping of brake rotors is getting on the brakes hard to stop and then leaving your foot on the brake pedal.

this leads to:

* uneven cooling across the entire rotor
* uneven pad material transfer to the rotor

the uneven cooling is caused by the pad remaining in contact with the rotor....the other parts of the rotor will cool at a different rate since it is exposed to air. the part where the pad is still in contact will cool slower as the pad remains hotter longer.

the uneven pad material transfer is also caused by the pad remaining in contact with the rotor. you can see this if you've ever done a hard stop and left your foot on the brake pedal - the rotor will have an outline of the pad etched into it.


to prevent "warping", don't keep your foot on the brake after coming to a hard stop (unless you absolutely have to).

to try and alleviate the effects of 'warping', perform the bed-in procedure for the pads. this will transfer more pad material evenly across the rotor in an attempt to fill the peaks and valleys caused by the uneven material transfer. you may have to perform the bed-in procedure more than once depending on how 'warped' your rotors are.

if the metal on the rotor itself is warped, then there's only one way to resolve that - replace the rotors.

[Migeta22]

cool! thanx for the info Majestic, I'll keep that in mind but there are just one of those red light or emergency moments that requires hard braking. maybe I can try leaving it in neutral to let them cool off.

[gdimiter]

I have pulsating brakes for some time and I did some research. What I found out is that most of the time the rotors themselves have excessive lateral runout (aka warped rotors), but any of the following may also cause lateral runout which translates into pulsating brake pedal (and it is not the ABS):
1) Rust or burr on hub or hub hat
2) Hub is bent or the hub itself has runout
3) Over tightening of lug nuts with impact gun and socket
4) Rust shower, (particles caught between hub and rotor) from impact gun and socket (during install)

Number 3 happened to me last spring when I mounted my summer tires. The lug nut were so overtighten that I barely managed to loosen them with a torque wrench. My plan to get rid of the pulsating is to measure the lateral runout of the rotors using a dial indicator and then find out a shop that can do on-the-car lathe of the rotors. Installing new rotors may not solve the problem if the cause is not in the rotors.

A quick question, does anyone know a shop in the GTA which can do an on-the-car lathe of the brake rotors? I found several shops in Buffalo, NY but it is kind of a long drive for such a thing.

I hope this info helps.

[nuttygent]

Just remember one thing guys, a lot of people will change their front rotors and the new ones will warp again after a short time. This usually means that the rears are not helping and are usually seized as they get the majority of the crap thrown back from the front wheels. If the fronts are over worked they will warp, lessons learned from many brake changes.

[Migeta22]

so I guess you check the pads for even wear all around? how else can you check if the rear brakes are seized?

[nuttygent]

If you remove the caliper assembly and the pads don't slide in and out easily they're on the verge of seizing up. When installing new pads and they seem tight, don't leave them like that, if anything file the surfaces that come in contact with the caliper so they move easily with a good anti-seize grease or compound.

[notthesnail]

Rotors almost never actually warp. Aside from mounting issues that force them out of shape, the pulsing will almost always be from uneven pad material transfer. This will result from, as stated above, leaving your foot on the brake after a hard or lengthy (like down a hill) stop AND:

worn rotors - not enough mass left to disipate heat effectively
poorly designed rotors - same as above and/or bad cooling design
poorly designed pads - usually cheap replacements

Re-bedding the brakes should fix the problem, but will likely be a temporary fix that you will have to repeat. If it's time for a change, look for OEM or good quality replacements. Don't go cheap. Centric and ATE are good names for inexpensive rotors. Don't forget to flush the brake fluid.

[Zoom Zoom Boy]

Rotors almost never actually warp. Aside from mounting issues that force them out of shape, the pulsing will almost always be from uneven pad material transfer. This will result from, as stated above, leaving your foot on the brake after a hard or lengthy (like down a hill) stop AND:

worn rotors - not enough mass left to disipate heat effectively
poorly designed rotors - same as above and/or bad cooling design
poorly designed pads - usually cheap replacements

Re-bedding the brakes should fix the problem, but will likely be a temporary fix that you will have to repeat. If it's time for a change, look for OEM or good quality replacements. Don't go cheap. Centric and ATE are good names for inexpensive rotors. Don't forget to flush the brake fluid.

Actually, on the 04' to 06' model years, warped front rotors on the original OEM rotors from factory is fairly common within the first 60-70K. Actual warped rotors. Not because of pad transfer.

[Kappa]

the most common cause of warping of brake rotors is getting on the brakes hard to stop and then leaving your foot on the brake pedal.

this leads to:

* uneven cooling across the entire rotor
* uneven pad material transfer to the rotor

the uneven cooling is caused by the pad remaining in contact with the rotor....the other parts of the rotor will cool at a different rate since it is exposed to air. the part where the pad is still in contact will cool slower as the pad remains hotter longer.

the uneven pad material transfer is also caused by the pad remaining in contact with the rotor. you can see this if you've ever done a hard stop and left your foot on the brake pedal - the rotor will have an outline of the pad etched into it.


to prevent "warping", don't keep your foot on the brake after coming to a hard stop (unless you absolutely have to).

to try and alleviate the effects of 'warping', perform the bed-in procedure for the pads. this will transfer more pad material evenly across the rotor in an attempt to fill the peaks and valleys caused by the uneven material transfer. you may have to perform the bed-in procedure more than once depending on how 'warped' your rotors are.

if the metal on the rotor itself is warped, then there's only one way to resolve that - replace the rotors.

i was going to say that warping rotors is pretty much impossible but this kinda explains it. its super rare to warp the the rotor its self... most of the time its just the layer that the brake pad leaves behind when you step on the brakes that you feel.. :)

[Migeta22]

Actually, on the 04' to 06' model years, warped front rotors on the original OEM rotors from factory is fairly common within the first 60-70K. Actual warped rotors. Not because of pad transfer.

wow, thats me right there, 06 Sedan with OEM rotors and pad and just hit 60,000Km. so I guess I should just replace it huh?

[mazdilla]

Actually, on the 04' to 06' model years, warped front rotors on the original OEM rotors from factory is fairly common within the first 60-70K. Actual warped rotors. Not because of pad transfer.

That's me right there.

Installing Magnum Cross-drilled cadmium coated rotors/ceramic organic pads/ss lines/ Dot 4 tomorrow.

[maz06]

Yup i had to do the same thing and the handbreak cable as it was seizing a bit in the back, I was at 85k however.