Suspension & Brakes Springs | Shocks | Handling | Rotors

Rotors...

Old 09-12-2009, 01:03 AM
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Default Rotors...

Has anybody had this happen to there rotor?...My right back rotor has ripples from the brake pad that is non-exsistant..here's the head kicker the front part of the rotor is in perfect shape and the brake pad still has a lot of meat...wtf... why is the back worn out with no brake pad and the front seems to be tip top? Can anybody shed some light on this mystery?
Old 09-12-2009, 07:23 AM
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Sounds like your caliper is/was sticking. Either the piston is stuck or the guide pins need to be replaced or lubed.
Old 09-12-2009, 05:17 PM
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thanks man...i just noticed that the left back rotor has the same ridges, to me the right side feels worse but if they both have ridges....is that normal? are the rotors suppose to have ridges on them?
Old 09-12-2009, 05:26 PM
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what are you calling ridges. do you mean concentric grooves along the rotor surface. rotors are not supposed to have them. a few, shallow ones are alright. if they get deep, thats because the pad is worn down to the rivets. change your rear brakes, inspect the calipers. see if the slide pins are free, and check for a stuck piston. have the rotors cut or buy new ones. lube the slide pin well when you reassemble.
Old 09-12-2009, 05:34 PM
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that's what i'm calling the ridges the grooves....and these aren't shallow maybe so on the left but both sides don't seem normal....how much would getting the rotors cut cost and is it usually cheaper to buy new rotors? thanks for the advice..
Old 09-12-2009, 07:41 PM
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Most places charge about $10/rotor. Call your local auto parts store and see what they charge. If they are grooved too badly they will not be able to cut them and you will have to buy news ones. Don't put the new rotors on until you fix the calipers. You can try rebuilding them yourself if you feel up to it or see how much new calipers cost.
Old 09-12-2009, 10:12 PM
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Originally Posted by oxblood!z28
that's what i'm calling the ridges the grooves....and these aren't shallow maybe so on the left but both sides don't seem normal....how much would getting the rotors cut cost and is it usually cheaper to buy new rotors? thanks for the advice..
Just buy some new, good quality rotors. Cutting rotors is an old practice and isn't recommended in a high performance application. When you cut a rotor, you're removing metal and effectively making the entire rotor thinner. This makes it much easier for the rotor to warp from heat cycling, and can also lead to stress cracks as well.
Old 09-13-2009, 12:16 PM
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My opinion on cutting rotors.......In regards to thickness, OEM's design rotors to work properly up to a predefined minimum thickness. This minimum thickness is etched/cast into the rotor (usually in mm). As long as you do not go below the minimum thickness specified, you should be okay. If you have grooves, you will likely need new rotors anyway.

Having said that, if you are racing the **** out of your car on a regular basis, you should probably upgrade your brake system.
Old 09-13-2009, 01:12 PM
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Originally Posted by BlackGT5
My opinion on cutting rotors.......In regards to thickness, OEM's design rotors to work properly up to a predefined minimum thickness. This minimum thickness is etched/cast into the rotor (usually in mm). As long as you do not go below the minimum thickness specified, you should be okay. If you have grooves, you will likely need new rotors anyway.

Having said that, if you are racing the **** out of your car on a regular basis, you should probably upgrade your brake system.
Agreed!
Old 09-13-2009, 02:53 PM
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cutting rotors is perfectly safe as long as you stay above the minimum thickness. it is also now suggested by GM itself, that you dont cut the rotors unless needed....like in the OP's case. having them cut used to cost $6 ea. now, youll be lucky to find it for under $15 ea.

if they are really deep, just buy new ones. at the least, take them to a shop and see if theyre salvageable. either way, the rotors arent your problem. your calipers are bad. either the piston or slide pin is stuck. it might be cheaper and easier to just buy brand new calipers and put them on, with new pads and rotors. at least that way youre 100% new and have a date when they were installed. just be sure to lube the slide pin, and check the lube every 20k or so.
Old 09-13-2009, 04:44 PM
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my oreily's cut a friend of mines scions for me for $10.
Old 09-18-2009, 04:21 AM
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whats up yall..So I got down and dirty and went to town on my brakes and rotors with brake cleaner and to my surprise i still have brake pads and my rotor don't seem as bad as i thought. However I noticed that the brake calipers said PBR made in Australia is that your standard brake caliper for a stock 2000 z28?...I also notice that the after cleaning the brakes and and rotors i don't seem to have that grinding noise as much, could that mean anything?
In any case I got a set of rear rotors and Hawks HPS rear brake pads coming in Saturday i'm hoping that will make a big diffrence...
Old 09-18-2009, 04:28 AM
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Originally Posted by EchoMirage
what are you calling ridges. do you mean concentric grooves along the rotor surface. rotors are not supposed to have them. a few, shallow ones are alright. if they get deep, thats because the pad is worn down to the rivets. change your rear brakes, inspect the calipers. see if the slide pins are free, and check for a stuck piston. have the rotors cut or buy new ones. lube the slide pin well when you reassemble.
How shallow should the grooves be to not be concerned about the rotors, just for general knowledge because i have a set of rotos and brakes coming in....thanks man
Old 09-18-2009, 08:00 AM
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Originally Posted by oxblood!z28
However I noticed that the brake calipers said PBR made in Australia is that your standard brake caliper for a stock 2000 z28?......
Yes calipers are from PBR (now owned by Bosch)
Old 09-18-2009, 08:01 AM
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Originally Posted by oxblood!z28
How shallow should the grooves be to not be concerned about the rotors, just for general knowledge because i have a set of rotos and brakes coming in....thanks man
This goes back to minimum thickness. That is your guide. Do not use rotors below the min. thk.
Old 09-18-2009, 09:10 PM
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Originally Posted by oxblood!z28
whats up yall..So I got down and dirty and went to town on my brakes and rotors with brake cleaner and to my surprise i still have brake pads and my rotor don't seem as bad as i thought. However I noticed that the brake calipers said PBR made in Australia is that your standard brake caliper for a stock 2000 z28?...I also notice that the after cleaning the brakes and and rotors i don't seem to have that grinding noise as much, could that mean anything?
In any case I got a set of rear rotors and Hawks HPS rear brake pads coming in Saturday i'm hoping that will make a big diffrence...
Yep, PBR calipers came stock on all 98-02 F-bodies.

Hawk HPS pads are a good choice.
Old 09-18-2009, 10:56 PM
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Originally Posted by oxblood!z28
How shallow should the grooves be to not be concerned about the rotors, just for general knowledge because i have a set of rotos and brakes coming in....thanks man
just guessing, if you can drag your fingernail across the surface and not really get stuck, its alright. if it gets stuck in the grooves, get them cut.
Old 09-24-2009, 10:45 PM
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Originally Posted by EchoMirage
cutting rotors is perfectly safe as long as you stay above the minimum thickness. it is also now suggested by GM itself, that you dont cut the rotors unless needed....like in the OP's case. having them cut used to cost $6 ea. now, youll be lucky to find it for under $15 ea.

if they are really deep, just buy new ones. at the least, take them to a shop and see if theyre salvageable. either way, the rotors arent your problem. your calipers are bad. either the piston or slide pin is stuck. it might be cheaper and easier to just buy brand new calipers and put them on, with new pads and rotors. at least that way youre 100% new and have a date when they were installed. just be sure to lube the slide pin, and check the lube every 20k or so.
Ok so i put on the new rotor and hawk brake pads....and thought i solved the problem...but i'm still hearing the metal to metal sound....when you say check the piston if its sticking how could you tell if it is....and how do you know if the guide or slide pins need to be replaced...when i checked them they were pretty easy to remove but the grease looked dryed out....
Old 09-24-2009, 11:04 PM
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you can tell you need new calipers when your rears are wearing faster than the fronts.... you need new calipers.. seriously.... if you want to be cheap, re grease the slide pins with brake silicone.. also is your harware clean? did you clean up the rust underneath the hardware? regardless, you need new calipers... otherwise this MIGHT fix your noisey brakes
Old 09-25-2009, 07:58 AM
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if you can remove the slide pins, theyre fine. just make sure you use proper brake lube grease. it may come with the pads. if not, just get a can from any parts store. make sure the slide pin doesnt have any rust on it, that its clean and smooth. if there are rust spots, clean it up with sandpaper. grease it heavy, make sure the rubber boots are in good shape. you can also just get a brake hardware kit, which will have new pins, boots, and rattle clips. might as well just do that.

using either an old brake pad and a c-clamp, or a big pair of channel locks, press in the piston. in the rear there is only one. see if you can press it in. if you can, and the rubber boot around it is alright, then the piston is fine. make sure you bleed it properly afterwards.

what metal to metal sound are you hearing. are you sure its from the rear. it may just be an abutment shim touching the rotor.

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