kurtdog

Ive got a 98 GS400 with 53K and I am hearing a break noise when I step on the pedal at slow speeds. The sound is muffled but I believe it sounds like a bed squeeking. It appears to be coming from the front. I just replaced the front breaks 6 months ago and the back brakes about 2 months ago. I used factory lexus pads btw. When breaking at high speeds, I do notice vibration especially breaking at high speeds going downhill. Do I need to turn my rotors?? Are they warped? What else could it be? My rotors looked fine when I replaced the brakes so I did not turn them at all.

Thanks in advance,

Kurt

P.S. I forgot to mention, the noise is a pulsating noise and not a constant noise.

bitkahuna

iTrader: (20)

Vibration during braking at least means the rotors aren't even, but it could mean they're warped it just worn out.

You need to get 'em checked out.

HaydenGS

I told the dealer that my rotors might be bended because my car shakes violently during high speed braking ..

have it checked.. they said the test showed that my rotors are even !


they couldn't fix my problem ... !!!

SandRock

I have a similar problem. I have to turn off the radio, put the car in drive and I can hear the brakes draging. I hear it more when I am slowing down. I was told when I brought the car that the breaks were new and the rotors were turned???

lextec

kurtdog, your rotors are the most likeky culprit for both your squeaking/noise & your brake pedal vibration, especially high speed down a hill. Sounds like you didn't have your rotors turned when you replaced the brake pads. Also, if you replaced the pads yourself, did you forget to install the anti-squeal shims that are on the factory pads? If so, just remember that Toyota/Lexus spent thousands of dollars developing these shims. You see, brake noise will always be there even if we don't hear it. The engineers have designed these shims in a way that it changes the resonant frequency of the pad application to a higher frequency that we as humans are not able to hear! So, in short, please don't forget to install these shims in the order that you found them. Getting back to your pedal vibration/shimmy. Did you have a knowledgable technician inspect your rotors for you? If so, was runout within spec, parallelism, were there hot spots on the rotor, were they discolored/overheated? A few of the many questions that should be answered in order to properly diagnose your source of shimmy. For example warped rotors can't be seen by the naked eye, usually. Parallelism is just as difficult to see. You need precision measuring tools to accurately display the results of your findings. Usually it's parallelism that is the culprit for brake shimmy, this is when your brake rotor's thickness varies widely(not to exceed .004")This happens over the course of normal use, so it can happen to anyone. Have your rotors measured & turned to a safe minimum & all should be well. Good luck & happy new year!

fasthuh

iTrader: (1)

There seem to be alot of talk about brakes sqeeking, mine does not do it yet, but I do feel a bit of a wobble when braking at high speeds, I will get my rotors turned, but I would like to replace the pads when I do it. Do you have any recommendation on which brake pads to use. There are the Toyota ones, which ofcourse will do the job, but are there any other pads that will give a better performance? However, I do not want to sacrife my rotors being burnt out or warp due to high heat.

Let me know if you have any recommendation or just stay with stock pads.

One more question to the people that has replaced their tranny fluid, did your service guy drop the pan or just drained and refilled? I will be doing the maint, I just want to do it right.

...fasthuh?

Mean Gene

Fast - I just use the drain plug at 15k intervals ( I have the Dragon T/C so I change more frequently than the manual says ). At the 45k mile mark ( just turned it ), I dropped the pan so I could remove & clean the mesh filter - not much debris there ). Figure to keep up this schedule until I get rid of the car.

ShowGSLuVv

I was talking to a Salesman from a Toyota Dealership and he told me that for lexus cars, whenever u replace the brake pads that u have to make sure you get Non metalic, because if you get Semi-metalic, then it'll damage the rotors bad, and u'll have to get those replaced as well...

fasthuh

iTrader: (1)

Mean, thanks for the info, I might just drop the pan, I read on previous messages that there is no gasket, is that correct? And did you replace the drain plug after you removed it? I had to replace the one on my previous car (Yukon) when I changed it.

Show, thanks too, I will be giving Steve a call again

...fasthuh?

kurtdog

Lextec,

Yes, I did replace those shims exactly as they were installed when I replaced the pads. Now, the noise has mysteriously disappeared. Could it be the pads just needed breaking in???
The vibration has not disappeared though. The vibration was not there with the old pads before I replaced them. I did not turn the rotors because I was not having any problems and their surface looked good. I was just trying to prolong the life of the rotor. Now with the new pads, the vibration appears. I also rotated the tires at the same time - could it be a tire balance problem?? Since my tires are directional I can just rotate them from back to front and vice-versa.

Kurtdog