Brakes ! (new brakes, loud cracking noise '95)
10-05-08, 10:26 PM
#16
Driver School Candidate
when I installed a set of Brembo rotors the holes for the mounting screws did not match up. I've been running without them for 8000 miles so far and no difference.
10-06-08, 09:08 AM
#17
From your response JBrewster i take it you do not know but because you said so it must be . That may well be a good enough reason for your logical reasoning as an answer but for me it is not.
How many cars have 4 piston calipers ? Is it because the car weights a great deal and slowing it down is an important part of its equation ?
I have driven with the screws and without them as well as not torquing them down tightly as the heads were stripped over a period of months for each . No other changes made but screws.
I now keep 10 on hand at all times. I must just be crazy , right?
It is to keep a rotor which heats up changes shape and its rotation on a as true a plane as possible . Why it makes a difference in compared to other cars is unlike other cars the LS does not have a floating caliper which glides back and forth with a warped rotors ( AKA pedal vibration ) . It instead has 4 pistons which have to hold a pad and work independently since the frame they are held into is in a fixed position.
Now in regards to the little skinny screws doing nothing . The diameter is quite large as well the surface area of them well and take up for their size by being angled to apply maximum force without the size. They are used to center and hold the position of the rotor in relation to the hub and caliper at all times and reduce run out.If it made no difference and studs held all the weight why do so many weird people go out and by centering rings. After all it is only the hub that little 2 mm lip can't hold anything , can it?
It is all physics and it makes sense , unfortunately not to you but gladly it did to a Lexus engineer. I am not one , but i do understand that before i start undoing anything and pretending i am an engineer i should figure out the pros and cons.
pro it works like ti is supposed to .
con it costs me $1 more to change my rotors .
BTW as far as the assembly line thing goes , if that were even remotely true ever car under the sun would have the screws or atleast every toyota .Besides once the caliper is in place probably by the next man on the assembly line it would no longer be needed. I am sure Toyota would have found a better allocation of resources (AKA funds) and used a paperclip as they use many other temporary clips in the installation process.
Now if you find fault with anything i am saying please explain it to me with the same rational i used as to why .
I have found when it comes to posting if i don't know about something , i just don't respond .
How many cars have 4 piston calipers ? Is it because the car weights a great deal and slowing it down is an important part of its equation ?
I have driven with the screws and without them as well as not torquing them down tightly as the heads were stripped over a period of months for each . No other changes made but screws.
I now keep 10 on hand at all times. I must just be crazy , right?
It is to keep a rotor which heats up changes shape and its rotation on a as true a plane as possible . Why it makes a difference in compared to other cars is unlike other cars the LS does not have a floating caliper which glides back and forth with a warped rotors ( AKA pedal vibration ) . It instead has 4 pistons which have to hold a pad and work independently since the frame they are held into is in a fixed position.
Now in regards to the little skinny screws doing nothing . The diameter is quite large as well the surface area of them well and take up for their size by being angled to apply maximum force without the size. They are used to center and hold the position of the rotor in relation to the hub and caliper at all times and reduce run out.If it made no difference and studs held all the weight why do so many weird people go out and by centering rings. After all it is only the hub that little 2 mm lip can't hold anything , can it?
It is all physics and it makes sense , unfortunately not to you but gladly it did to a Lexus engineer. I am not one , but i do understand that before i start undoing anything and pretending i am an engineer i should figure out the pros and cons.
pro it works like ti is supposed to .
con it costs me $1 more to change my rotors .
BTW as far as the assembly line thing goes , if that were even remotely true ever car under the sun would have the screws or atleast every toyota .Besides once the caliper is in place probably by the next man on the assembly line it would no longer be needed. I am sure Toyota would have found a better allocation of resources (AKA funds) and used a paperclip as they use many other temporary clips in the installation process.
Now if you find fault with anything i am saying please explain it to me with the same rational i used as to why .
I have found when it comes to posting if i don't know about something , i just don't respond .
Those screws are tightened far less than the 80ft/lbs that the lug nuts are tightened to, yet you think those screws hold the rotor. Those screws would be sheared off if the rotor relied on them to hold it while braking. You can't compare them at all to the hub, which may be only a few mm in thickness, but has an overall diameter of about 3", which the weight of the car is evenly spread across. There are many cars with fixed calipers like the fronts of the LS that don't utilize set screws. There are also many cars with floating calipers that do utilize set screws.
Rotors don't "warp" either. The vibration you feel would come from brake pad material not deposited on the rotor evenly. Under repeated high heat situations, the unevenly deposited pad material can cause the rotor to get much hotter in that area which causes the iron to transform into cementite. This cementite does not get completely removed when you have the rotors turned which means that the vibration will come back within a few thousand miles.
I'm not running set screws on my LS and it is perfectly fine. I also didn't replace the set screws in my brother's Accord (which only has floating calipers) and it is fine as well.
10-06-08, 09:57 AM
#18
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I don't run the set screws either....no problems on my 98 LS. Without the screws it is a total pain in the butt to get everything back together with out the set screws holding the rotors in place.
Regarding the cracking sound......Does it do it when you are standing still, in gear, and you pump the brake pedal?
Regarding the cracking sound......Does it do it when you are standing still, in gear, and you pump the brake pedal?
10-06-08, 10:04 AM
#19
I don't run the set screws either....no problems on my 98 LS. Without the screws it is a total pain in the butt to get everything back together with out the set screws holding the rotors in place.
Regarding the cracking sound......Does it do it when you are standing still, in gear, and you pump the brake pedal?
Regarding the cracking sound......Does it do it when you are standing still, in gear, and you pump the brake pedal?
10-06-08, 10:29 PM
#21
Pole Position
Thread Starter
no it doesnt crack when i pump the breaks only when im slowly driving and i suddenly break but not at high speeds ?
i bought the screws today i have to put them in after school tmrw
and then we will c if that is the problem
i bought the screws today i have to put them in after school tmrw
and then we will c if that is the problem
10-07-08, 06:28 AM
#22
Did you replace the shims and use "Brake Quiet" or something similiar? My brakes made a crackling sound at slow speeds until I changed the pads and shims.
10-07-08, 01:18 PM
#23
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Did you grease the shaft the caliper pivots on? That was the cause of my cracking noise.
10-07-08, 09:59 PM
#25
Pole Position
Thread Starter
hmmm
didnt try greasing that but i will tmrw and im gna put the screws in
cant get around to it with school and work my springs are comin in this week should put them in sat
=)
cant get around to it with school and work my springs are comin in this week should put them in sat
=)
10-08-08, 11:27 PM
#26
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When i replaced the screws the slight wobble i had was gone. Also the clinking from the rotor hub hitting the studs.
You will believe what you would like and that is fine . At Least try and prove your point which i still do not see being made.
Those small stupid little screws do a job whether you believe they do or not. They are part of the equation to hold the rotor in place so they do not get held loosely and slam into the studs over and over again .
Then again you also believe rotors never warp ,so why bother ?
As you mentioned cementite it is " a hard, brittle material " which means it should easily be removed by a brake lathe.
2nd point is is rotors never warped then why would they go out of spec and get thinner if all you are doing is removing material from the surface .'
You need to stop listening to whoever is feeding you this crap as it makes no sense. Sorry but bringing up something as ludacris as cementite just sank you battleship .
You will believe what you would like and that is fine . At Least try and prove your point which i still do not see being made.
Those small stupid little screws do a job whether you believe they do or not. They are part of the equation to hold the rotor in place so they do not get held loosely and slam into the studs over and over again .
Then again you also believe rotors never warp ,so why bother ?
As you mentioned cementite it is " a hard, brittle material " which means it should easily be removed by a brake lathe.
2nd point is is rotors never warped then why would they go out of spec and get thinner if all you are doing is removing material from the surface .'
You need to stop listening to whoever is feeding you this crap as it makes no sense. Sorry but bringing up something as ludacris as cementite just sank you battleship .
10-09-08, 05:44 AM
#27
Pole Position
Thread Starter
so yest i took apart the breaks looked at them for a good time and came to the conclusion that my brother did not put on the backing plates on the pads so i took them off the old pads and through them in on one side. im thinking that the pads were lose and making that sound when i put them on i didnt hear anything in the passenger wheel so today im going to do the other side and hopefully that will be it if not im going to have to re thread those holes for those screws then ill let you guys know
10-09-08, 07:53 AM
#28
When i replaced the screws the slight wobble i had was gone. Also the clinking from the rotor hub hitting the studs.
You will believe what you would like and that is fine . At Least try and prove your point which i still do not see being made.
Those small stupid little screws do a job whether you believe they do or not. They are part of the equation to hold the rotor in place so they do not get held loosely and slam into the studs over and over again .
Then again you also believe rotors never warp ,so why bother ?
As you mentioned cementite it is " a hard, brittle material " which means it should easily be removed by a brake lathe.
2nd point is is rotors never warped then why would they go out of spec and get thinner if all you are doing is removing material from the surface .'
You need to stop listening to whoever is feeding you this crap as it makes no sense. Sorry but bringing up something as ludacris as cementite just sank you battleship .
You will believe what you would like and that is fine . At Least try and prove your point which i still do not see being made.
Those small stupid little screws do a job whether you believe they do or not. They are part of the equation to hold the rotor in place so they do not get held loosely and slam into the studs over and over again .
Then again you also believe rotors never warp ,so why bother ?
As you mentioned cementite it is " a hard, brittle material " which means it should easily be removed by a brake lathe.
2nd point is is rotors never warped then why would they go out of spec and get thinner if all you are doing is removing material from the surface .'
You need to stop listening to whoever is feeding you this crap as it makes no sense. Sorry but bringing up something as ludacris as cementite just sank you battleship .
http://www.stoptech.com/tech_info/wp...rakedisk.shtml
10-10-08, 01:38 AM
#29
Pole Position
Thread Starter
so i this is what the noise was
my brother changed my pads he did not put the backing plates on the new pads from the old ones i put those in and vualla no noise
so i guess the bolts are not needed =)
my brother changed my pads he did not put the backing plates on the new pads from the old ones i put those in and vualla no noise
so i guess the bolts are not needed =)
11-12-08, 05:43 AM
#30
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I have the same issue, the dealer deny anything but suggest an $800 spare parts replacement to try and see
Can you send me a pic of how the backing plates look like? I am driving a RX300 2002
Thanks in Advance
Can you send me a pic of how the backing plates look like? I am driving a RX300 2002
Thanks in Advance