Weird Brake Problem

[mybbis]

Hey all, I am new to this forum and I just got my 06 IS250 RWD back in December of 08. I got a hell of a deal on it. Needless to say I am very pleased with the car. However there is an issue with the front brakes that I don't know what to do about. The car has been to the dealer 3 times, everytime they say "we've fixed it you are all good to go" I take the car home just to find out the car still has the problem.

This is how it started. When I bought the car after the first day, I realized my brakes were squeeling everytime I applied like medium pressure. Me being around autos and working on them for a long time, I ran my finger across the rotors. Both front rortors had decent size lips on the them, so I knew they had to be turned. I researched about the IS brakes and heard about the $600 brake service. Just purchasing the car I didn't have the money to spend on that kind of service. Being the dumba$$ I am I took the car to Just Brakes and they said would turn my rotors for $60. So I dropped the car off and me and my wife went shopping and picked the car up later. It was perfect no squeeling, no noises I was very happy. A couple of days later while I was in stop and go traffic I hear like a "creaking/ grinding" noise coming from the front while applying the brakes. First thing I thought was maybe the lugnuts were loose a little. Checked them and it wasn't it. The next day I took the car to Just Brakes and told them about it. They took the car and examined everything and said they has no idea what was making that noise, they did drive it and confirmed there was a noise. My next step was taking it to the dealer. I went in and the dealer took the car and checked everything. They had it done in an hour and a half. They said I had a loose bolt on my caliper. I also told them about the new brake pads and the low dust and they replaced everything at no charge. I took the car home and when I left the brakes were good. Noise came back a few days later. I took it back again. This time they had my car for 3 days. They said they could not find out what was going on and that lexus might have to make a case out of my car. Great I just bought this car. Well the next day they called and said they found the problem. They replaced my drivers side rotor under warranty. So I was happy and took the car home. About a week later the noise comes back again. So, routine I take it back again and told them that this time it had sounded like it was coming from the passenger side and maybe the solution was to replace the other rotor too. I droppped off the car again. They didn't replace the rotor but they did lubricate all parts and did the fuel lines recall and all that. Again I picked up the car and same story, it was good and then about a week later same result. ( sorry this is a long story just stating all the facts )The last time I brought it back they told me that I would have to bring it back when a representative from lexus is there to observe it, which is on the 9th of FEB. So as of now I'm driving my car creaking and grinding to a stop :( I need some opinions do you think Just brakes screwed my rotors? are you not supposed to turn the rotors on this car?why would this happen from just turning rotors? If the dealer doesn't help me with the brakes should I just upgrade to aftermarket rotors? I'm not really worried about performance much, I just want the car to drive and sound like a Lexus! any input is greatly appreciated

thanks

[IS250_rookie]

I've heard that there was a TSB for squeeky brake pads...that might be what you have.

[mybbis]

I've heard that there was a TSB for squeeky brake pads...that might be what you have.

They replaced the front pads the first visit!!!!!

I just don't get it

[IS250_rookie]

I've heard that there was a TSB for squeeky brake pads...that might be what you have.

They replaced the front pads the first visit!!!!!

I just don't get it

Well I read your post and it said they replaced them with the less dusty ones. There are two types of brake pads...the ones that fix the brake dust issue, and the other ones that fix the squeal. The reason the first type of pads fixes the dust issue is because the pads are made out of a harder material, also sometimes they can start to squeal aswell. I don't have any experience with this since I still have the stock dusty pads.

[mybbis]

I've heard that there was a TSB for squeeky brake pads...that might be what you have.

They replaced the front pads the first visit!!!!!

I just don't get it

Well I read your post and it said they replaced them with the less dusty ones. There are two types of brake pads...the ones that fix the brake dust issue, and the other ones that fix the squeal. The reason the first type of pads fixes the dust issue is because the pads are made out of a harder material, also sometimes they can start to squeal aswell. I don't have any experience with this since I still have the stock dusty pads.

well there is no more squeeling just that grinding creaking noise. I'm not sure which pads they put. I do know they dont dust hardly at all

L

[Randy&Bonnie]

..

[mybbis]

Trying to analyze squeaky, squealing brake noise over the internet is like trying to sniff flowers thru your butt.

When exactly do you hear the noise? Is it as squeal, or a grind? Is the noise there constantly or intermittent? Is the noise there when you light press the brake pedal? Does the noise get louder when your brake harder?

Diagnosing a rotor/pad sound should not be that difficult. These rotors are apparently soft and thinner than normal. The lip on the rotor outside the pad contact area is normal wear. Lexus told me that the rotors can only be turned once and then will have to be replaced on our IS250 with the front brakes serviced at 47,000 miles.

I have noticed that when I drive the car after sitting all night, the brakes have a slight grinding noise, very noticeable as I back out of the garage and into the street, and louder than "normal" to me. After a couple stops, the noise disappears.

There are a couple possibilities: if the rotors are not concentric (out of round) they may oscillate as they rotor on the axle hub, causing the pads to move as the caliper pistons press against the pads and contact the rotor. These rotors "float" on the axle hub over the lug studs, and are tightened via the lug nuts against the wheel. When you tighten floating rotors, you need to be sure to tighten the nuts gradually applying torque in a sequence, similar to torquing the head on an engine. Otherwise, if a Just Brake guy, in a big hurry with a his big compressed air impact wrench torques the first lug nut down hard, it can pull the rotor and apply a slight tilt when it sits on the wheel hub. If the machine work on the rotor was out of spec, you could have too much rotating movement that is out of concentricity, either side to side or up and down. Again, a close visual inspection should clue a good mechanic in.

It could also be defective pad material (the compound has a big chuck of metal in it. If the noise is squeal sound, it could be the bad of the pad (metal) is rubbing on the piston with a slight oscillation causing noise. Also, depending on your climate, and how your drive, a slight "glaze" can develop on the pads and rotors and you need to brake hard several times to "clean" it off. I notice when I wash the car, the shiny rotors get rusty immediately. Then when I pull the car into the garage, the brakes will grind slightly. The next morning when I pull the car out of the garage, the brakes will squeal for a few seconds as I back out onto the street. The squeal goes away immediately at the first time I hit the brakes.

The first thing I'd do is jack the car up, and turn/spin the wheels by hand and watch and listen. If I can't see oro hear any abnormal movement or sound, I'd pull the wheels, pull the pads out and examine them. I'd look closely at the rotor surface - on both sides to see if there is any unusual rough surface area. A typical brake squeal is caused by two surfaces rubbing together with some degree of oscillation, like the back of pads rubbing against the caliper pistons (there is a special lubricant for this condition). A grinding sound is usually caused by two dissimilar surface textures, or disimilar material that don't like each other, or the introduction of an extraneous substance (like when you get a little rock between the pad and the rotor). Last resort, I'd replace the rotors and pads.

That's just my worthless opinion. :P

Let us know what you find out.

Thanks for replying randy. I know its difficult to diagnose the problem over the Internet but I dont know where else to look. I have tried taking the wheels off because I also thought the rotor might have been tilted as you said. The noise is kind of intermittent. This morning it was 30 degrees and I drove 50 miles to school and it was fine. Yesterday coming to and from work It was doing it. I do think they might have cut the rotor down too much but I'm not sure. I think if the dealer would replace the passenger side rotor it would be good since it seemed to fix the other side. By the way I drive the car easy, and it still makes the noise while slow and medium braking. It doesn't squeel. And I'm pretty sure it is the rotor because the noise goes with the same speed the wheels are turning. Does that make sense? I guess I will have to wait until the 9th and see what the dealer has to say. The best way to describe the noise would be like a rocking chair rocking back and forth. Thanks for your input

[Randy&Bonnie]

..

[mybbis]

Trying to analyze squeaky, squealing brake noise over the internet is like trying to sniff flowers thru your butt.

When exactly do you hear the noise? Is it as squeal, or a grind? Is the noise there constantly or intermittent? Is the noise there when you light press the brake pedal? Does the noise get louder when your brake harder?

Diagnosing a rotor/pad sound should not be that difficult. These rotors are apparently soft and thinner than normal. The lip on the rotor outside the pad contact area is normal wear. Lexus told me that the rotors can only be turned once and then will have to be replaced on our IS250 with the front brakes serviced at 47,000 miles.

I have noticed that when I drive the car after sitting all night, the brakes have a slight grinding noise, very noticeable as I back out of the garage and into the street, and louder than "normal" to me. After a couple stops, the noise disappears.

There are a couple possibilities: if the rotors are not concentric (out of round) they may oscillate as they rotor on the axle hub, causing the pads to move as the caliper pistons press against the pads and contact the rotor. These rotors "float" on the axle hub over the lug studs, and are tightened via the lug nuts against the wheel. When you tighten floating rotors, you need to be sure to tighten the nuts gradually applying torque in a sequence, similar to torquing the head on an engine. Otherwise, if a Just Brake guy, in a big hurry with a his big compressed air impact wrench torques the first lug nut down hard, it can pull the rotor and apply a slight tilt when it sits on the wheel hub. If the machine work on the rotor was out of spec, you could have too much rotating movement that is out of concentricity, either side to side or up and down. Again, a close visual inspection should clue a good mechanic in.

It could also be defective pad material (the compound has a big chuck of metal in it. If the noise is squeal sound, it could be the bad of the pad (metal) is rubbing on the piston with a slight oscillation causing noise. Also, depending on your climate, and how your drive, a slight "glaze" can develop on the pads and rotors and you need to brake hard several times to "clean" it off. I notice when I wash the car, the shiny rotors get rusty immediately. Then when I pull the car into the garage, the brakes will grind slightly. The next morning when I pull the car out of the garage, the brakes will squeal for a few seconds as I back out onto the street. The squeal goes away immediately at the first time I hit the brakes.

The first thing I'd do is jack the car up, and turn/spin the wheels by hand and watch and listen. If I can't see oro hear any abnormal movement or sound, I'd pull the wheels, pull the pads out and examine them. I'd look closely at the rotor surface - on both sides to see if there is any unusual rough surface area. A typical brake squeal is caused by two surfaces rubbing together with some degree of oscillation, like the back of pads rubbing against the caliper pistons (there is a special lubricant for this condition). A grinding sound is usually caused by two dissimilar surface textures, or disimilar material that don't like each other, or the introduction of an extraneous substance (like when you get a little rock between the pad and the rotor). Last resort, I'd replace the rotors and pads.

That's just my worthless opinion. :P

Let us know what you find out.

Thanks for replying randy. I know its difficult to diagnose the problem over the Internet but I dont know where else to look. I have tried taking the wheels off because I also thought the rotor might have been tilted as you said. The noise is kind of intermittent. This morning it was 30 degrees and I drove 50 miles to school and it was fine. Yesterday coming to and from work It was doing it. I do think they might have cut the rotor down too much but I'm not sure. I think if the dealer would replace the passenger side rotor it would be good since it seemed to fix the other side. By the way I drive the car easy, and it still makes the noise while slow and medium braking. It doesn't squeel. And I'm pretty sure it is the rotor because the noise goes with the same speed the wheels are turning. Does that make sense? I guess I will have to wait until the 9th and see what the dealer has to say. The best way to describe the noise would be like a rocking chair rocking back and forth. Thanks for your input

Yeah, it does sound like the noise is related to the rotation of the rotor. I takes less than 10 minutes to replace a rotor on that car. I would think the dealer would just replace the rotor and see if that fixes it.

Legally, the rotor can only be turned down so much according the thickness spec. range, I believe that is DOT law. Any good brake shop should mic the thickness before and after it's turned. I've had a brake shop, say "no they are too thin to turn" and they would be out legal spec. I then I took them to another shop, and they turned them with no problem.

I am not a machinist, but I would think that the amount that needs to be removed from the surface is just very small, enough to smooth the surface, or correct any warp. Usually, if the rotors are warped, due to excessive heat, turning them will NOT fix them, they will warp again almost immediatley.

Keep us posted. Good luck.

would my problem more than likely be that since the rotor is too thin it is moving while braking?