I can't seem to figure out the problem. I know there is a leak somewhere, just wanted to know where to start looking for the failure spots in the brake system. My pads are squealy when I come to a stop under light pressure, and when parking and barely braking. They also squeal when the brakes are cold, and I'm just pulling out of the garage and driving. They have a "speed determined" rhythm, i.e. the squeals come in pulses in accordance to how fast I am driving. Once I get above around 30 mph, the sound stops, until I come to a stop. The process repeats until the brakes are warm, or when I've just been using the brake a lot. Once they're warmed up, they squeal less, but its still there.

Parking brake used to come on frequently and actually stayed on, I added fluid since it was low, and readjusted everything parking brake related, and now the parking brake light is fine. It does however turn back on when the fluid is low. The fluid doesn't lower substantially, but every week it's like 1/4 of the way down. I'm wondering if this has anything to do with why my brakes are so squealy, because I have cleaned the shims, and backings and applied that "brake disc quiet" goop to the backs of the pads, and the shims. I also noticed that I do have a leak (garage floor has brake fluid on it) and I can't seem to figure out where its coming from. Anyways, long story short, I would like to know if anyone has an idea on how to get rid of squeals, and what parts of the brake system are common problems.

 

A leak would be very obvious to see . You would need to jack up the car and see the line physically and check for leaks . I also would recommend checking your brake pads and your brake disc runout. Cause intermitent brake squeal are sypmtoms of a warp disc or worn out pads .

 

fluid loss and squeeking may be related.

if your brakes are leaking at the caliper you should have brake fluid on the inside of that wheel. since brake fluid does not evaporate it should be very easy to probe around w a dry finger to locate your leak.

you probably have a brake rotor that has runout. more runout than .003" will cause a speed dependent brake wobble. you may be able to have your rotors resurface/ground. any good parts/brake store can do it.

the wobbling may have cause a brake caliper piston to abrade the rubber seal causing your leak. generally it is just a case of replacing the rubber seal/O ring.

once you get your rotors trued and the caliper fixed buy yourself of EBC Green brakepads. you won't believe the pedal feel, lack of dust, noise, how nice your rotors look after a few thousand miles and how well the car stops. all pads are not the same and you won't run anything but EBCs after you take them for a spin.

btw, make sure you are dealing w a reputable shop as to the rotor resurfacing.... if the rotors are thinner than the minimum spec you will need new rotors. if they are o k to grind by all means don't buy new rotors.... just have them resurfaced.

generally the rear rotors are the culprit due to the emergency brake. if you have used your brakes aggressively, causing your rotors to be warm/hot, do not immediately park the car w the emergency brake on as it will distort the rotor...

good luck,

howard coleman

 

Good stuff, Howard...especially the EBC Green pads.

Also, as the front calipers are alloy, the material will become more porous over time, and allow fluid to slowly pass by the seals-even though they are perfect. In this case, you either need to replace the caliper, or have it re-sleeved with stainless steel, which is about $50-$75 per caliper. Don't forget they are now over 10 years old....

 

ok, I just looked for the leaks, and it turns out its a clutch line. Its the line thats right underneath the map sensor on the firewall. I ordered it from Malloy just the other day, and hopefully it'll stop the clutch from grabbing instantly. I've noticed that when I'm doing the parking thing, on and off the clutch, or stop and go traffic, the clutch pedal grabs instantly when I let off, then it sags the hell out and seems to not give any power to the car. This problem sucks. I no longer think the fluid loss has anything to do with the brakes squealing, but now I guess I have 2 problems. Grr. Thx for the suggestions, I'll look into getting those pads, and getting my rotors turned. And can any brake shop resleeve my calipers? I haven't seen an ounce of brake fluid on any of the calipers. Time to take it to a reputable brake shop somewhere around here.

 

Should have opted for a stainless steel unit. I think they are less expensive than the stock rubber replacement and will more than likely last a lot longer.

 

well, I have the part in hand, it came in today. Should I bleed the fluid somewhere? I don't know how to bleed a clutch line, I've only bled calipers for the brakes. The fluid taps off the same reservoir, and I'm wondering if theres a slave cylinder or something that I'd need to bleed to get the air out of the line. And ya, I should have gotten a stainless, but I guess this will do for now.

 

There's a bleed screw on the slave cylinder. Same basic principle as the brakes, but you don't pump the pedal to build up pressure each time.

In other words, open screw, push pedal down to the floor, close screw. Do not allow the pedal to travel upwards any amount while the screw is open (same as brakes). Repeat several times. The line is obviously far shorter than a brake line, so it takes much less to cycle the fluid through.

 

Yep, the clutch pedal will stick to the floor, so once you close to bleed screw you have to pull the pedal up.