Has anyone had any issues with their rotors warping? My evo keeps overheating the right rotor and warping it. The first time it happened at about 1000mi, so i took it in about 1500 and they turned both rotors...i know i know, these rotors shouldn't be turned, but its a temp fix until we figure out the problem!

Then at about 2500 it began to warp again as i headed out on a 3500mi road trip. About 600mi in my rotors were warped bad again and i had to use my Nav to find a mitsu dealer in tenn. Well they turned them both again so i could at least make it to my first stop in Va. 400 mile later i was in Va and thats where i realized it was the right rotor warping (Right wheel was way hotter then the rest and COVERED in brake dust) So they replaced the caliper and right rotor only. Took off to NY, felt fine, as i got to Vt i noticed the warping comming back. So on the return home to Ar from Vt (two day drive) it got really worse again. Tried to get it turned but the dealerships were closed for the evening so i had to limp it the remaining 1000mi. Now that I am home i have given it to the my local dealership to begin working.

Any ideas what else could be causing the right caliper to stick? I am thinking bad brake lines, or something is out of spec. It appears to be the inner pad that is rubbing constantly.

While they are working it i am going to have them replace the driver side rotor since it has been turned twice and is .8mm from being to thin.

The car is stock minus a drop in filter, and hasn't been to the track. Any help would be great....i am pretty good with cars, but this one is throwing me for a loop. Sorry for the long post.

 

I'd say either bad line or bad master cylinder. It could even be something to do with ABS/traction control forcing the brake to be on to keep that tire from slipping but that would be pretty hard to diagnose.

 

I'm stumped. Bad brake line to that wheel maybe?

 

hummm, bad master cylinder...good place to start.
As for the ABS thing, i though about that...but i should get an ABS light, or the audible ABS sound you get. Neither of which happen.
I will mention the master cylinder to them on monday. Thanks

 

Thats kind of what i think too.

 

That seems like what the problem is.

 

it sounds as-if it could be that in that line pressure seems to remain constant for a while after you release the brake . Or it may be a condition within the ABS pump which is allowing fluid to pass oneway but be very slow to bleed back and release pressure . Of it could also be a bad caliper ( which may well be the case ) . I've seen both conditions give the same results . If you can take it to the dealer it may be best because that caliber is expensive and so it the ABS pump . If you cannot take your car to the dealer for one reason or the other you may wanna take off that caliber and inspect the pistons which may be sticking .



Frank

 

they replaced the caliper and it did it again.

 

yeah originally i thought it was the caliper as well. But since the problem came back with the caliper replaced, i now suspect something along the lines of the brake pressure not bleeding off properly.

 

Interesting -

I would normally suggest the same thing that occurs to most EVO's. Overheated pads making a sloppy transfer layer leading to a pulsing pedal.

In your case though the excess heat/dust of course does indicate that likely a pad is dragging. What's the pad wear look like? Inner or outer pad show excessive wear?
...edit reread post - hmmmm

Are the pads able to retract ok?
On a side note - don't you love how dealers are so quick to take your very expensive rotors and just turn them and send you out...

 

Yeah the pads "seem" feel like they release alright. The car doesn't pull to right on the highway.

Yeah and your right about the eagerness to turn the rotors. When i got the rotor and caliper repalced, the service guy told me the bill to Mitsu is $1800 for just parts. I am willing to turn the rotors right now till we find the fix. But once the problem is solved, i want new rotors. You wouldn't buy a new car with used brakes would you? I figure for the price we pay for these cars, we deserve the best.

On another note, do you all thnk i should fight to get the wheel bearings onthat side replaced or looked at as well. My thought is if there is enough heat to warp the one device on the car designed to take on extreme temps, what else in that area could be effected from the heat. Seeing how the wheel bearings are right there, and aren't ment to take on extreme heat, what kind of damage could i have.

 

Do you brake from high speeds? If so do you do it to a full stop and keep the brake pedal pressed?

Not blaming you so don't

 

Quick question. Is this only happening in the rear? If yes, are you doing any hand brake braking?

 

its the passenger side front rotor that is warping.
As for the hard braking, i rarely do any high speed hard braking, but if i have to, i never keep the brake pedal down after a hard stop. I know if you do a hard stop and dont let the car roll and set the pedal that will warp a rotor too.

 

^ I have more brake dust on my right front passanger wheel also. I have noticed since the day I bought the car that the right front passenger wheel would accumilate brake dust faster than all the others. I am now at 7k miles and have no warping of the rotor or any brake problems though.