DCNASER

You guys may remember I installed new brakes (HWAK) and drilled rotors on my GS300 2006. I know it takes few days or maybe a week for the brakes to settle and take position with the rotors, but I still hear it like it is still new. This weird rough noise especially when going down hill and applying the brakes. The brakes fell good and grab as should be, but the noise is weird for new brakes and rotors. I had a friend look at them, and he said they look great with no issues. Any suggestions?

whlkev

is it like a swooshing noise kinda?

that's normal for cross drilled rotors..

DCNASER

Hmm, not sure what you mean by swooshing, but I feel like the whole front end is fixing to come off , lol, it's scary. If it is normal, why do the drilled ones make this noise?

DCNASER

Well, I know the sound of new brake pads , when you first put them on, that is not what I mean if that's what you referring to.

whlkev

describe when you hear the noise? usually I could hear it when windows are down at lower than 20mph or so, I've had hawks and brembo drilled rotors on my old car..

If i remember correctly from reading up on it, it's because how the heated air escapes through the drilled rotors that cause this very distinctive wooosh sound

if you feel like the car is about to fall apart when u brake, then something is wrong

Stormforge

maybe not swooshing, it could be whirling sound? i remember when i had slotted rotors on my TL, there was a whirling sound as the brake pad hit the slots. could be something similar with dcnaser's, the pads hitting the drilled holes. if that is the case, it's perfectly normal. however to be on the safe side, get a mechanic to confirm everything is OK.

DCNASER

I would see I hear it more during hot weather. At night, it is at least 50% less. Worst when I do an abrupt stop, but no clicking or tapping, just the same noise over and over, only if I brake hard. I don't drive it much, but for a Lexus, I don't think these rotors are meant to be like this, are they? What you mean heat gasses dissipate? Don't you think a regular rotor would do worse due to gases unable to escape? Or am I wrong?

DCNASER

I found the right word, lol, I would say it feels like scraping. I heard some guys talk about bedding? Can I still do that after I drove over 150 miles on them? Am sure this is an idiotic question.

whlkev

scraping huh....

here is the instruction on how to bed in ur new brakes/pads:
http://www.zeckhausen.com/bedding_in_brakes.htm

be careful while attempting that..

and yes, you can still bed in ur brakes now, and of course regular rotors will be worse, as you continue to press on your brakes, the hot air will be formed on the surface of the rotors and this is called the brake fade, that's why crossed drilled and slotted are ideal for spirited driving.

and now that you have aftermarket brakes, it is no longer "lexus" so of course u can't compare to how it's supposed to be when it's stock.

rominl

iTrader: (4)

i also wonder if you break in correctly? it's important to bed the pads on the rotors nice and even otherwise noise will appear

DCNASER

I did some bedding yesterday, even though I am not satisfied with it because I couldn't really find a comfortable area to do it at. There is no empty space anywhere! I guess it is better now. But I noticed that with windows up or down at night, it is definitely so much better at night times, as if I couldn't hear it at all. It happens usually at noon times, and usually at the same downhill close to my home. Weird