bukhumnoi2000

iTrader: (5)

I'm going to get new pads .. I have not decided yet but maybe project Mu or Ferodo 2500 .. I am thinking of just replacing the fronts and resurface the rotors.

I don't abuse my brakes but it seems that some who do don't have this problem. It's one of those things that is hard to troubleshoot down to the root cause. Some of the cause are.. defects in the manufacturing, pads, owners washing their brakes while hot or drive through a puddle while brakes are hot. Over torquing lug nuts, installing after market wheels that does not allow sufficient cooling of brakes....

In our case... I will start off with just replacing the pads and resurface the rotors then if that doesn't fix the problem I will replace the rotors and the pads again.

Ty-Evo8

iTrader: (8)

I am not trying to hijack this thread or anything but it seams that everyone is talking about something I just noticed myself on my car.

When I am driving around town (less than 50mph) I do not feel anything wrong with my brakes. They stop without creating any noise or vibration in the peddle or stearing wheel. But I noticed in the last few weeks that when I am on the highway doing 60-85mph and press on the brake I get vibration (left and right movement) of the stearing wheel. So much so that I can see it quite clearly! I take it easy on my brakes, I downshift whenever possible to avoid using brakes to prolong there life.

(trying to get to the point here....) I have an oil change come Monday. I plan to have Mitsu mechanic take a ride with me to show him the problem. What could be causing this? Is it the rotors? I just don't get it. I had an 02' wrx before this and never had any problems. This is my first car with Brembo type brakes and am clueless as to what is happening. If it is the rotors, I get from the previous posts that having them resurfaced is a risk and often causes other problems or is a waste of money.

Any suggestions / advice would be appreciated, I don't want to be screwed by the dealer !

GreedMOTO

iTrader: (3)

I'vr got the highway shimmer as well and most of my thread searches have resulted in one thing. The rotors are NOT warped in a true sense, the pads a improperly bedded. This pissed me off b/c I broke in my breaks like a saint and I have problems now at 13k.

I'm just gonna shell out the bucks for some Brembo Cross drilled rotors and some Hawk pads, do the break in like They recommend and see what happens.

Ty-Evo8

iTrader: (8)

I may have improperly bedded break pads? I don't understand I don't break late like some people do, I ease into it and come to a gradual stop.

Please someone explain to me how to seat brakes properly so that this doesn't happen in the future. Does this mean that all I have to do is replace the pads and everything will be back to normal? Is this at all dangerous to have? Is this going to create more problems with my brakes or rotors in the future? I don't have the money to shell out at the moment and was hoping to just live with the problem until I can afford new aftermarket pads and rotors.

Thanks for the help in advance.

Evo D

My '03 has about 10K on it, I have had the steering wheel pulsing on braking from 50 mph and higher off an on since about 3k. Since it is especially bad at the moment, I checked the rotors with a dial indicator. Driver's side measures no run-out, right side varies from about 0.000" to 0.003". Since the shop manual says the limit is 0.0012", obviously I'm out of range on that rotor. I'm wondering though before I look into have the rotor(s) turned if the problem may be due to pad material deposition. No kidding, I took GREAT CARE in not abusing the brakes on this car early on (car had only 4 miles on it when I got it, so I don't think anyone else did either) and I do not hammer the brakes repeatedly from triple digit speeds or anything of the kind. Given the size & supposed superiority of this expensive "name brand" brake hardware, you'd sure as hell expect them to hold up better under pretty normal street driving. One thing I have noted a number of times with this car however is if it is left to sit for several days or more, especially if "put away wet", the pads stick to the rotors such that you have to break them free with the engine to get the car to move. I have noted after this there will be a clear black spot/outline where the pad had been stuck. Anyway, when you sand the rotors, does it matter how, i.e., should you move the paper in a circle around the entire disk (so the scratches produced would be parallel to the direction of rotor travel) or should you move the paper radially, i.e. from the hub outward (scratches perpendicular to rotor rotation)? You'd think there might be a chemical which would aid in this process, maybe when used with something like a scrubbing pad, etc. When I have the rotors off for this, would it be of any use to sand the face of the pads a bit, maybe to remove glaze? Also several posts mention "reseating" the pads. How exactly is this done?

Lastly, what would be the best replacement rotors & pads for normal street use? After this experience, I'd be pretty relucatant to go with Brembo rotors. Any use stoptech?

TIA,

Dan

infantsam

iTrader: (1)

a random pattern is the best........

And the caliper is Brembo - it doesn't mean the rotor is - I suspect Mitsu's supplier made it to Brembo's 'specs' - but that is only my opinion

Evo D

The rotors are marked "Brembo" as well.

Dan

EDIT-The question of the maker of the rotors came up awhile back right after I had gotten the car, in this same shimmy issue context as I recall. Here's a link to some pics I posted at the time showing the "Brembo" marking on both front & rear rotors. Rotor marking

bukhumnoi2000

iTrader: (5)

The break in for any pads/rotors are nothing special. It's just simply use them like you normally would the first 300 miles or so. Basically don't do brake checks to see if ABS works.


These shimmer problems are warranty items. Mitsubishi being cheapo's are extremely reluctant to replace your pads or rotors, especially when it's the first time taking it in for the problem. They simply will shave down the rotors and do NOTHING ELSE. (At least that was in my experience, even though I wanted new rotors and pads since my car only had 3K and the problem surfaced at 1K miles)

It is EXTREMELY difficult to pin point the root cause for these shimmering problems. From my experience the most common cause are 1. defects of rotors, pads, or both 2. washing rotors or driving through puddles while the rotors are really hot. 2000 Model Toyota Tundras had this problem... do you know what Toyota did to anybody who brought their truck in with that complaint? .... They replaced the pads and rotors, no questions asked.

This is like my 10 vehicles own and besides the Tundra I've never had any issues with brakes. I'm pissed off about it because it's a "Brembo" and Mitsubishi simply just turns the rotor... especially when I read about so many complaints about it. 3 of 7 Evo owners here in my local area have the same problem.

Though I should take it in again for warranty repair and perhaps they'll replace my rotors since this is the 2nd time and the car only have 6K miles.

Instead of taking it in... I have a complete set of Ferroro 2500 pads on hand and will pull the rotors out next week and take it down to the local brake shop to be turned ($10/each) and see if the new pads will fix the problem. I think it will.

infantsam

iTrader: (1)

Not being arguementative but many things are marked by a contracted manufacturer with a 'brand name'
That said most often OEM rotors are usually of good quality iron......producing parts for an OEM is far different from producing aftermarket stuff.

Because OEM suppliers are subject to FMVSS specs and various other accepted quality standards like ISO etc. The paperwork itself is staggering..

CLeeEvo

I took my car in for alignment the other day (which they did a horrible job, another thread). They also bled the brake fluids. When I got it back and test drove it, I noticed that the front right rotor were making grooves. It's noticable, but not too deep. You can feel it if you run your finger nail over it.

From what you guys are saying, I shouldn't resurface the rotor right? Also, should I have them take out the brake pad and check for something that's causing the groves? I'm just worried that the grooves will go deeper... Thanks.

Evo D

The same argument could be made for the calipers. I would be very surprised if for the relatively small number of rotors (and calipers) involved here they weren't simply supplied by Brembo to Mitsubishi. That's what they make, brakes, why would they not make these? I any event it's really a distinction without a difference; even if Brembo did allow them to be made under their name, by Mitsu or anyone else, once they license the use of their name they should reflect Brembo "quality", whatever that may be.

Having said that, I have noticed that after the process of removing the wheels to measure the run out and replacing the wheels, the problem has very substantially disappeared. Since I did not touch the pads at all or do anything to alter the rotor surface other than dragging the small tip of my dial indicator across a tiny portion of it, I am beginning to wonder if the problem does not originate between the rotor and hub. This is not the 1st time it has "come and gone" on this car; if it reoccurs I will measure the run out again, pull the offending rotor(s) and be sure there is no rust etc. between the rotor and hub preventing proper alignment.

Dan

Evo D

Ah yes wheel alignment. Another one of those things which in my experience it's almost impossible to get the "pros" to do right. Unfortunately it's one of the few things which are all but impossible to do yourself, due to the equipment involved. It's a pretty straightforward operation if you have the gear, they simply don't give enough of a **** to do a good job. Again, in my experience.

Slight grooving you can feel with your fingernail is normal and not a cause for resurfacing.

Dan

****??? Wow, censorship. On a web site with a bunch of guys (mostly, I'm sure) discussing cars? You've got to be joking...

infantsam

iTrader: (1)

i agree - in actuality i believe the foundry name is bradi for rotors - but now they are owned by brembo - some sort of bailout or something.

its probably a lot of calipers when you add up EVO/STi/350Z/G35/SpecV/ and now some cadillacs!! - Brilliant move by brembo

Are you measuring runout by mounting the indicator and rotating the rotor on the car? If so what do you mean by it varies between .001 and .003? The maximum amount of movement is your TIR. Also, if removing and reinstalling fixes it that is bizarre - are you overtorquing lug nuts??

Evo D

The run out measured on the driver's side was 0.000 (indicator resolution is 0.001), on the passenger 0.003 (indicator is attached to the strut in the usual way with the tip against the outer face toward the edge, as described in the shop manual). Spec is max 0.0012. I'm the only one whose taken the wheels off this car (again, had 4 miles on it when I got it) & the lug nuts are torqued to 75'#'s. I don't know that the rotor/hub relationship is the issue, but one thing's for sure, the rotor didn't magically "unwarp" itself. Have to measure again, at the moment I'm just enjoying the no-shimmy braking & leaving well enough alone. I just got a set of Michelin Pilot Sports A/S's from tire rack, now I have to find someplace to mount them (ANOTHER one of those things you can't do yourself which I've had BAD LUCK with from the "pros"). Maybe when I do this I'll take the opportunity to check the run out again.

Dan

infantsam

iTrader: (1)

hmmm
so back up and reanalyze for a moment

if you have uneven pad deposition or "Disc Thickness Variation", as the rotor spins the pads hit a 'thicker' part of the rotor. This pushes all of the pistons back and furthermore pushes fluid back into the MC (back and forth at highway speeds - SWIM) I think this would be felt in the brake pedal but not necessarily the st Wheel.

If you have excesive runout then as the rotor spins you have 2 pistons getting pushed back in and at the same time 2 pistons pushing out. This would not likely be felt in the brake pedal (the fluid is going from one side of the caliper to the other - but not back up the brake lines) but if the runout is 'enough' you are rapidly moving mass back and forth (the caliper pistons in a fixed caliper design (EVO) or the entire caliper in a floating caliper design. This I think would be felt in the steering wheel.

And if you feel it both in the pedal and the wheel then you may have a combination of both

From my experience .003 is not that bad for runout....the compliance in the system can handle it. And - while iron does have some memory etc once it is warped it is warped - even turning it would only be temporary. But specs for DTV are in the ten thousandsths (.0002 - .0004) - much more sensitive than runout

So if it fixed itself I would suspect uneven pad deposition which under a few more hard braking events the transfer layer gets smoother and shimmy goes away. If you have stock pads and this continues to re-occur I would bet you are getting them hot enough to transfer unevenly - and sometimes it's worse than others. I'd bet a better pad bedded properly would help.

Garnet paper can help and some use certain race pads (Hawk Blues I think) as a 'scrubber' to remove the bad layer so bedding can be redone.

Does that make any sense?