Brake Shudder - On The Hunt For The Problem. Over Heated Brake Fluid?

[masda74]

Where do I start.

I have upgraded parts of the OEM brakes and have done the following:

I got braided lines put in on all four corners. I have changed the rotors to T3s. Pads have been changed as well.

Once the brakes were upgraded, there was a better feel to the braking. The pedal did not have that sponge feeling where you kept pressing and the brakes would not activate.

Now with the upgrade, the pedal does not have to travel as much to have that bite.

Recently I went out on a run with .stripes and SteveR. We had a bit of a spirited run up Mundaring area and there was some high speed braking.

With the high speed braking came the shudder. At first I thought it was just overheated rotors that caused the problem.

Progressive braking after that still had the shudder and brake performance reduced, even though it was not high speed braking.

After cooling down a bit,it was still there every so often. Since then I have had this intermittent shudder with the brakes.

It does not happen all the time and it seems that it only happens at certain speeds or possibly how I apply the brakes.

I am yet to determine at what speed and if under hard braking.

I know that if I use light braking, it is not there as much. under heavy braking, the steering wheel sometimes vibrates with the shudder.

Sometimes I get the feedback through the pedal. is that even possible?

I suspect that it may have to do with the control arm bushes as mentioned by .stripes.

I will get this looked at, during the next alignment at Malaga suspension.

I went to MT and got them to go for a drive. They came back and said nothing was wrong.

I know that there is an issue as the car never had this issue before.

Last night as part of general maintenance, I had a look at the brake fluid.

Keep in mind that the brake fluid was done recently.

Does this look normal?

[Bizkets is Drunk?]

mine does it to. that brake fluid looks rubbish.

[masda74]

^{but the brake fluid was recently replaced. it is the dot 4 pbr stuff that comes in a red bottle.}

^{Why would it have that cloudy crap in it? looks like the brake fluid was not replaced.}

[polishboi.luke]

don't think the quality of the brake fluid will cause brake shudder to be honest. run a dial gauge over the disc and check the run out?

[polishboi.luke]

overheated brake fluid will give you a spongey pedal. and In extreme cases no pedal at all(very scary) ive been running protex grooves for about 2 years now done 20k km and ive got a heavy foot ive done 240km down to 100kmh quick stops and my brakes are still going strong. my standard rotors before that I replaced did 5000km fed them to the monkeys they were bent like a banana

[masda74]

I did have a pokie around the right wheel when I removed the wheel on the weekend. didn't seem like there was any run out on that rotor.

I did a visual check, but best to get it checked out the right way. Could also be the left side that is causing the issue.

Is it cheap enough to buy the dial or not worth the hassle? Cost too much?

[hawlass]

Masda, replace your control arm bushs (nolathane) and hubs, you will be sorted. Mine were wobbly too.

I have done these as well as T3's and pads. Heavy repeated braking through a long gorge racing scenic touring with a mate (private gorge road of course) . His xr8 yoot was pouring smoke off the very wobbly brakes and mine were and still are sweet.

[masda74]

cool. thanks for confirming this. Just out of curiosity would it be best to get the bushes done while getting the shockworks gear installed.

Or does it not involve getting the bushes done. Just want to save coin in labour costs.

[PTR_NITRO_FG]

Suspension out = easier access to bushes?

Therefore saving labour $$$ ?

[Bizkets is Drunk?]

how do you know they are farked