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Hey guys, as the name suggests i was wondering what are the negatives on driving with warped rotors. My rotors have been pretty bad for a while, and didnt get them replaced since i was either tight on cash or simply didnt have the time to get them fixed as i needed the car for university. The skyline vibrates like crazy when braking from around 100ks +, and has moderate irretating vibrations under normal driving. Its clear the rotors are fked and i already know that braking has been tremendously compromised, but what i want to know is, are there any other factors that need to be looked at once i do replace the rotors. For e.g. would wheel bearings need to be checked? etc..

Also ive decided to get slotted rotors to avoid having this problem again but was wondering what pads i should use. Are pads the main cause of warped rotors? I realise some pads are harsh on rotors and wear them out quicker, but as long at they dont get warped and provide smooth braking every time then im willing to sacrifice durability for performance. I just hate when the rotors get warped. So yea any help will be most appreciated!

Cheers

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I was planning on getting them machined however its been around 10000+ks since the vibration started and its only gotten worse, im pretty sure its warped since this started the day ive been braking at 100ks+. Ive already purchased 4 slotted rotors but still thinking of what pads i should get. I heard ebc make good brake pads but i feel they might be overkill since i dont take the car to the track.

Just an update, i jacked up my car and spun the front left wheel and i hear this scraping noise, it appears during the 1st quarter of the rotation (in other words the noise isnt present during the full rotation). It sounds like a grinding noise and its present on both sides of the wheels, drivers side sounding slightly more harsh. However when i pull the wheel towards me and turn it, the noise disappears. Could this be the bearings? or just the warped brakes scrapping across the side. If it is the bearings, whats the consequence of changing them at a later date?

Cheers for the quick responses, and i will be sure to check the tie rods and bushes, ill get my mechanic to check them as well. So far i regret not changing the brakes sooner.

Seriously, rotors pretty much don't warp. You have to cook the crap out of them to get them to do it. As you have been advised, it is almost always pad binder deposition onto the rotor, and this can be removed by a hard thrash/rebedding procedure or with emery paper.

Slotted rotors are better at rejecting the binder material, not better at resisting warping.

Wheel bearings do suffer from the shuddering, so yes, consider them when you have the car apart. Besides which, they are old anyway, so will possibly be stuffed. Skyline wheel bearings often are completely buggered and don't show much sign of it.

Seriously, rotors pretty much don't warp. You have to cook the crap out of them to get them to do it. As you have been advised, it is almost always pad binder deposition onto the rotor, and this can be removed by a hard thrash/rebedding procedure or with emery paper.

Slotted rotors are better at rejecting the binder material, not better at resisting warping.

Wheel bearings do suffer from the shuddering, so yes, consider them when you have the car apart. Besides which, they are old anyway, so will possibly be stuffed. Skyline wheel bearings often are completely buggered and don't show much sign of it.

I see, yea i highly doubt i cooked the crap out of them so yea its too late since i already ordered the rotors. But im still unsure of what pads to get, im actually confused since my car is a non turbo so i dont know which pads would fit, all i keep finding is benedix general use pads, theres no higher performing pads anywhere unless i pay retail at the mechanic which is insanely high price. From my knowledge r33 non turbo 1996 has single piston caliper? am i correct? If i do choose to go with standard brake pads, how will they perform under heavy driving/braking compared to the more expensive pads, do they just get shredded easier or do they melt?

Take a pad out. Take a photo of it. Put the pad on a piece of paper and trace around it, then mark the dimensions on that tracing (height, width, etc). Send the above to gslrallysport. Ask for street pads.

If you were after a retail solution I'd just suggest Bendix Ultimates. They are certainly not the best pad out there, but they do perfectly fine on a street car. I used them for many years, and would again. There are a number of more aggressive options available these days that are more interesting, but Ultimates still work. Anyway, Greg at gsl will be able to guide your pad choice from what he has available, and he will have something available.

cheers

Take a pad out. Take a photo of it. Put the pad on a piece of paper and trace around it, then mark the dimensions on that tracing (height, width, etc). Send the above to gslrallysport. Ask for street pads.

If you were after a retail solution I'd just suggest Bendix Ultimates. They are certainly not the best pad out there, but they do perfectly fine on a street car. I used them for many years, and would again. There are a number of more aggressive options available these days that are more interesting, but Ultimates still work. Anyway, Greg at gsl will be able to guide your pad choice from what he has available, and he will have something available.

cheers

Cheers mate, ill go for the benedix then! =) Im pretty sure they are similar to ferodo pads as well, anyways got another dilemna, this one really pissed me off, turns out the rotors i bought was for turbo charged skylines (or n/a skylines with 5 studs), so they require 5 studs while my car supports 4. Is it possible to drill 4 different holes so the rotors will fit?? Its so stupid cause i purchased the rotors according to dba's database which says that the r33 gtst has the same rotor as the r33 gts25 (dba 4000 series). After doing a bit of research turns out the gts25 uses 280mm rotors as opposed to the 296mm found on gtst. You reckon if i get the rotors drilled it will work with my calipers?

Cheers

No way in hell. They'll be the wrong thickness, and of course, the wrong diameter. Return them or sell them on. Then contact gslrallysport.

Alright will do, Still dont understand why their database gave me wrong rotors =='

Anyways cheers mate.

Because the DBA database is shit. It's what they decided/guessed goes on each car - not information from the manufacturer.

Yea i agree with you there, got the rotors returned, i couldnt use any other disc manufacturer as a reference, cause they all required me to own a business and register or some shit. Anyways i got a refund which im happy with, im just going to get my current rotors machined as suggested, now i got 300 dollars to spare, might just do a service or something.

Cheers for the help.

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