Rominl and I are both engineers and I think Banana is too. I can buy your text book explanation, but as engineers, we also would like to see empirical evidence, right?

One of our local buddies "Jawnthen" is experiencing something similar to what has been discussed, so we'll surely be checking into whether his symptoms point to your cause.

 

good, time for engineering debug

 

I knew I was in good company. Are you guys all fellow ME's?

Anyway, the easy way to test it is to set the rotor, stop, and check it. Mine were moving sure enough.

Is your friend using chrome wheels?

 

nop, he has 20" wheels. i am in EE actually, and i think rmmgs4 too? but we both have some (i can't say extensive) insight on mechanic stuff

 

OK Romi, let's do it. What's the coefficient of friction for rusty rotors by the way?

Cyclemax, No Jawnthen does not have chrome wheels, but we definitely need to go through the process of elimination.

I was a 4th year ME before changing majors. The Silicon Valley / High Tech slump is getting to me though, so I am working on getting into real estate. Oops! Off subject.

 

another EE here

 

ee and me rule

 

We must also look at the net torque from the caliper based on its applied force times the distance from the rotational axis......

Actually a pretty cool problem IMO.

Anywho, the noise I got was pretty ugly sounding, but it would only do it once until I changed direction. And it only did it when I came to a complete stop. Wouldn't happen under normal slowing. Back and forth in the driveway was the best way to make it ring. It sounded like a ball peen hammer hitting, well, the rotor.

 

in that case i guess banana's reply makes a lot of sense?

 

cyclemax,
is your car still under warranty? if it is easy to recreate it, take it in, I am the lexus tech or any shop tech will have a lot more experience on this than any of us. Everyshop, including lexus, have a master tech, he is the guy that know everything, stop my and find out who the person is, have a quick talk with him.

 

first of all ya'll are geeks...lol but i am too...started out ME and switched to EE cuz I wanted to trick out my car stereo...but onto the topic of the thread...

yeah I get what cyclemax is describing. It sounded more pronounced today after I got my coilovers put on. However, they never removed the wheels during the installation. I dunno if that throws another variable into this problem. I did have the sound before but I didn't really pay attention to it much until Hermosa pointed it out at lunch today. I'll take a look it at some more tomorrow, but everyone's explainations seem correct.

Anyone have ideas to fix the problem?

 

Personally, I have a click when I brake in slow speed. Lexus had re-tighten every bolts under the car, no help, they finally find out that by brake pad is shifting. They are correct, i checked the brake pads , it has some room to shift, same on stock caliper. I had ordered a shim kit (back plate) for the pad (i have supraTT brake)

Installed the shims, no more clicking.

I had opened the calipers out several times, and remove the disc a few times to re-surface, I had to force the rotor out everytime.

I don;t see how the rotor can shift easily to make noise, unless the back of your wheel is not come in contact with the rotor. Verify that first. I don't disgree on this issue where the rotor is shifting, anything possible

I am posting a supra brake diagram, since I don't have a GS diagram, but all the parts for the brake system should be the same, use this to help us visualize that could cause this noise, I think my cousin gs makes some clicking noise also, I am not sure if lexus fixed for him yet, he is currently out of the country for vacation now. (diagram is for the rear, but the front is identical, the whole brake diagram is posted on mysite, undr DIY brake)

See the "anti-rattling spring" make sure that is install in the correct direction

 

yeah sure, get the ap racing brakes, hahaha.....

man, we need naother getogether for the problem

 

Jawnthen,
Your coming over to my place tomorrow right?


We'll check it out then.

PS. My stomach is not happy with the lunch we had today. How bout you and Hermosa?

 

what time tomorrow?