recurring brake rotor problem...
 

So I've been having a rather frustrating problem with my rotors causing brake pedal vibration. About 3 weeks ago I got brand new Napa premium rotors, and i'm already getting pulsation. Extremely frustrating.

I'm wondering if there's something about my install/bed in procedure that's causing it... or if I'm just having bad luck.

First question, do I absolutely need to get new pads every time I get new rotors? Or can new rotors be used with older pads with plenty of life left in them?

My process for installing new rotors:
1. clean new rotors with brake cleaner
2. Unbolt caliper and remove old rotor
3. wire brush axle flange/hub mounting surface to make sure its clean
4. Take pads off caliper, lubricate caliper slider and where the pad contacts the caliper (not sure what this channel thing is called)
5. Install rotor and caliper
6. Wire brush mounting flange of the wheel to make sure it is clean and free of debris
7. Install wheel and torque evenly to 85 ft lbs
8. Bed in brake pads to rotors using a 10-12 'firm' stops, increasing in speed, never coming to a complete stop.

Am I doing something terribly wrong? Am I missing something? I'm getting really frustrated with having to buy new rotors, and I hate brake pedal pulsation.

Kracka, Mustgofaster, I'm sure you guys have some insight on this.

Re: recurring brake rotor problem...
 

thats a pretty good procedure. how much rust is on the hub? if there is too much it can cause a pulsation. sometimes a wire brush isn't enough and you need to use a 90 degree die grinder and a green 3m roloc disk to get all the rust off.

Re: recurring brake rotor problem...
 

Your procedure sounds good. My guess is the pulsating is from pad transfer of some sort, which is slightly odd since you're using new rotors though (perfectly fine to reuse pads with new rotors, I am on my Evo). My suggestion is to remove the rotors and sand them by hand with some 120-grit until the surface looks shiny again. Try to do this evenly across all friction surfaces of the rotor. Also use the 120-grit to take a small layer off the face of the brake pads. This will give everything a virgin surface for bedding together.

Follow these bed-in procedures:
http://www.racingbrake.com/v/main/te...in%20procedure

Re: recurring brake rotor problem...
 

Alright, I'm gonna give it another try, but I may get new pads as well. I have no idea what kind of pads they are, some sort of ceramic, they came on the car. I just don't have any faith in them.

Any suggestions for a good street pad? I want something that doesn't have to warm up to be effective.

Re: recurring brake rotor problem...
 

Ceramics are a pretty good general street pad; I don't think its them causing your problem. Give my suggestions a try before throwing more money blindly at the problem. If you insist on getting new pads though list up how you use your car and what traits you're looking for in a pad and we can give some guidance.

Re: recurring brake rotor problem...
 

Those bed in procedures are basically what I've been doing...not exactly but very close. I just don't want to go for reproducing the definition of insanity here.

The most glaring thing about how that procedure differs from mine, is they say don't get below 25 MPH, which I probably had done when doing my bed-in with the most recent new rotors. Maybe that would make the difference?

Re: recurring brake rotor problem...
 

Ok how are you feeling the pulsation? Is it in the pedal, or on the steering wheel?

Rear brake pulsation usually is felt in the pedal, while front is felt in the steering wheel. It is typically amplified as speed increases.

Re: recurring brake rotor problem...
 

I will assume you are talking about the front. Are you sure the steering and suspension components are good? IE Wheel bearings, tie rods, ball joints?

Re: recurring brake rotor problem...
 

its the fronts. Wheel bearings, ball joints have about ~10k miles on them, as does one of the tie rod ends, the other one is fine.

Re: recurring brake rotor problem...
 

With a brand new brake rotor, there should be no shake at all. Is this shake starting immediatly after the install, or is it happening after a few day/weeks/months of driving?

If its happening immediatly I would have to say its something about the install. Rotor not seated on the hub properly would be my first thought.

If its happening after a bit of driving I would say your either really hard on your brakes ( I know that never happens) your rear brakes arent working properly causing your fronts to do all the stopping, or your calipers arent releasing. All of which would cause your rotors to heat up and warp pretty quick.

Re: recurring brake rotor problem...
 

well it started soon after (a week or so?) with only a very, very slight, hardly noticeable pulsation. It is just progressively getting worse.

Re: recurring brake rotor problem...
 

Replacement rotors these days are almost always low quality metal. Buy Brembo blank oem replacement.

Re: recurring brake rotor problem...
 

Have you lubricated the caliper slides at all? If you have break issues the only step you missed was a set of pads, yes it sucks your old ones have life left but if you want the breaking issue gone you must start new.

~John

Re: recurring brake rotor problem...
 

Centric 120's are very good rotors. These are the blank cores that Stoptech and Powerslot use. Some RotorPro sets also use these. Other RotorPro sets (seems random, no way to actually tell) use the Centric 121 cores which are your typical replacement Chinese junk; they're also sold under the C-Tek name. A few batches of Powerslots went out using these cores a while back, but now they're using only the 120's.

Re: recurring brake rotor problem...
 

good info kracka.

John - I'm thinking i'll be going in that direction the next time this happens. Things seem to be holding steady, maybe the cold has something to do with it. Early this spring for sure, I might just put down some cash on rebuilt calipers all around, new rotors, and some nice pads and start from scratch. I'm guessing there might be issues with my current stuff that I'm unaware of.

joseph sushi - I'm either gonna go with those or with some frozen rotors, as people say they stand up very well to warping.

nonetheless, i'm definitely not throwing another set of rotors at this setup without at least also changing pads. I just think they kinda suck for creating even pad transfer, and might not stand up to heat very well.

Re: recurring brake rotor problem...
 

Frozen Rotors are another that use the Centric 120 blanks. Beginning to see a pattern here? ;)

Re: recurring brake rotor problem...
 

so kracka, whats the best way to make sure what i'm odering is the Centric 120 blanks? Are those also what brembo uses, or do they have their own design altogether?

Re: recurring brake rotor problem...
 

I believe Brembo has their own made. The easiest way to make sure you're getting the Centric 120's is to just order them specifically. I just looked up your options and the Brembo blanks are slightly cheaper than the Centric 120 blanks. Both are good choices, but the Centrics do include a black electro-coating which will keep them looking nicer for longer if you care about that.

Re: recurring brake rotor problem...
 

well, looks like I know what i'm getting for my next set of rotors :)

Re: recurring brake rotor problem...
 

If you're referring to the Centric 120's with black e-coating you'll be very happy with them. I have a set on my Evo and they bed-in very nicely, seem to be wearing perfectly, and the coating still looks good. I got them from MAP. The guys who regularly track their cars report the Centric 120's being more durable than the stock Brembo rotors.

Re: recurring brake rotor problem...
 

yep, thats what i was referring to. Now to figure out which pads i'm gonna run, as well. Where do you go to figure out which kind of pads you will run? Any good sites with reviews and such?

Re: recurring brake rotor problem...
 

I think a good place to start would be talking to the shops and guys that actually race and have tried numerous different setups. RRE and Archer both highly recommend the Porterfield R4-S (carbon/Kevlar) for street, autocross, and light-duty track DSM's. You can also check out the EBC Green and Red compounds, the recently revised Red pads with Kevlar are supposed to be very good but historically EBC's offerings haven't been all that spectacular. If you're looking to keep things cheaper though you can just get some Metal Master Semi-Metallic pads. My advice though is to stay away from anything Hawk.

Re: recurring brake rotor problem...
 

why no hawk? Seems like a lot of chumpcar guys like hawk stuff.

Re: recurring brake rotor problem...
 

None of the Hawk pads are anything special. Overall, they're louder and dustier than their competitors while having no clear advantages or benefits. They may have been something special 10 years ago but they stood still while the industry progressed.

Re: recurring brake rotor problem...
 

Gotcha. I can't say i'm totally impressed with the hawk street pads on my jeep. They refuse to work when its wet (kinda scary actually) and they do require you heat them up a bit before they become effective at all. They don't make too much noise or dust though.

Re: recurring brake rotor problem...
 

Are they the Hawk ceramics? Ceramic is good at being quiet and low-dust, but its performance isn't much better than typical OEM replacements.

Re: recurring brake rotor problem...
 

yeah, ceramic

Re: recurring brake rotor problem...
 

Did you ever figure out your pulsation?

With my OEM 2G wheels, the backsides corrode so much that if I remove the wheel, and it goes on a different way, there is a vibration/pulsation from the front.

Are you sure the surface where the rotor sits was clean, free of rust, etc? (they pretty much always need to be cleaned)

I forgot what kind of rotor you used, but once and awhile a defective part makes it way on to a car. Bad machining/cheap casting/bad runout/etc.

Re: recurring brake rotor problem...
 

Its been manageable, I haven't yet changed my rotors again. I just don't have the skrill for it right now, and I want to do new pads at the same time, maybe even rebuild calipers to make sure everything is kosher. I'll do it come spring before rallyx/autox season.

But yeah, I wire brush both rotor hats and wheels before installing... so i think its good.

Re: recurring brake rotor problem...
 

Just to bring this back up from the dead...

I just overhauled my rear brakes. They were completely ineffective, so I think that more stress was being placed on my fronts. Probably not the only cause, but I'm sure it didn't help anything. One rear caliper was completely frozen (both piston and slider) while the other one just had a frozen slider. I got rear loaded calipers, installed new rotors, and bled out the entire system pretty well.

Unfortunately, the pulsating in the fronts is getting worse. At this point i'm pretty convinced it is in part the crappy unknown pads that are on there. I'm gonna order some new pads and rotors and see if that fixes it. If that doesn't help, my last course of action is new front calipers. Then there would literally be nothing else it could be.

Re: recurring brake rotor problem...
 

side note, has anyone used Axxis ULT brake pads?

I want some decent front brake pads, but I don't really feel like spending $150-200 on a super nice set right now, as I likely won't actually be doing any track days with this car, so I don't need a race set of pads. I just want something that will hold up well on the street/autox/rallyx.

These seem like a decent set for those purposes, and can be had for $77.50 shipped.

Re: recurring brake rotor problem...
 

I worked at goodyear for several years, I am not the best brake specialist in the world, but I am probably one of the most experienced here in said field.

Your rotors are warped, you need to replace them, Ive always used crappy pads with no problems, and I decelerate from illegal speeds to 30mph often.

I worked for auto value, and when we stocked rotors, we threw them as frizbees, and dropped many, just because you bought "new" rotors, does not mean that they are true.

check the warranty status on your rotors, and warranty them.

You have to understand that napa uses the worst quality metal from china, old cars melted down do not make good rotors, the inconsistency of the metal causes warping sometimes.

brembo blanks are the best quality OEM rotor money can buy.

Re: recurring brake rotor problem...
 

1 out of 3 NAPA rotors I install are warped out of the box. I swear the stock boys must drop kick them off the truck.

Try resurfacing them, I cut every new Napa rotor I install now.

Re: recurring brake rotor problem...
 

WTF!?

Point back to the cleaning of your hubs to see if that is causing the issue.

Also take your rotors in to have them turned, That will tell you for SURE if your rotor is warped or not. O'reilly does this service for you. if they aren't turnable they will tell you and not charge you. or just ask them to see if they are turnabout to begin with

Re: recurring brake rotor problem...
 

rotors don't normally 'warp' in the traditional meaning of the word, I believe it has to do with pad transfer, hot spots, hardening of the metal and uneven wear. As Kracka has said, and in my own research, it mainly does have to do with pad transfer.

Also, when they were new, they didn't vibrate at all. I would say that eliminates being thrown like a frisbee from the equation.

Are they crappy metal? Probably. They are NAPA premium rotors. Should they last longer than a few weeks before warping? Also probably.

And I'm really trying to asses the root cause here. Getting them turned would fix the problem for a few weeks.

I've got some Axxis ULT brake pads on the way! Then i'll get my rotors turned (or get some centric 120's) and see what happens.

Re: recurring brake rotor problem...
 

Alright, so I got some old rotors turned, got the AXXIS pads installed, and burnished in very thoroughly. Going by the books this time. Giving the brakes some time to cool off, and then i'll be out to test them a bit more. I have a good feeling about things this time :) After 3-4 brake jobs in the last year, I'm ready for these to last a while.

I closely inspected my calipers, I really can't imagine anything being wrong with them. The sliders move like butter, the pistons move smoothly and easily were pushed back in to make room for the new pads. I'm gonna rule them out.

Re: recurring brake rotor problem...
 

You do realize a lot of Brembos are made in China with varying consistency right? I'd take a Centric Premium over a Brembo blank if given the choice at an equal price.