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rotors dont warp. if you feel vibration during braking, you either did not bed the pads properly or there is excessive runout you will feel the vibration.

http://my.is/forums/f136/warped-rotors-410384/

Wobble is usually excessive runout, not "warped" rotors.

Runout can be caused by unevenly torqued lugs, a poor hub/rotor interface, runout in the hub or wheel bearing flange, etc

If you want another source beyond Stoptech and a 40-years-famous race engineer how bout the editor of Brake and Front End magazine?

Brake Tech Feature: 8 Myths that Could Be Holding You Back from Performing the Best Brake Job: Brake and Front End



article goes on to explain those in more depth
 

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Discussion Starter · #22 ·
Man I think I have reached my limit. I got my rear rotors turned and needless to say the jack rabbit who did it messed them up. Made a groove down the center. A friend of mine told me he could get me a new set for $60 wholesale. I bought them, installed with new EBC pads and the shit still have the vibration when I brake. The entire car shakes.
 

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Discussion Starter · #24 ·
Guys sorry form the late update. I got my issue resolved. I had my factory rotors resurfaced again this time by another shop and the guy did it on a slow cut. Also before doing so he grinned all the rust of the hub and on the inside of the rotors. Although the rust was not that much I guess it was enough to cause the vibration on braking.
 

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Any vibration in the steering wheel is most likely

-Warped rotors
-Worn wheel bearings
-Alignment issues
 

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Any vibration in the steering wheel is most likely

-Warped rotors
-Worn wheel bearings
-Alignment issues
Rotors don't warp as i posted above, and quoted below for convenience.

rotors dont warp. if you feel vibration during braking, you either did not bed the pads properly or there is excessive runout you will feel the vibration.

http://my.is/forums/f136/warped-rotors-410384/

Wobble is usually excessive runout, not "warped" rotors.

Runout can be caused by unevenly torqued lugs, a poor hub/rotor interface, runout in the hub or wheel bearing flange, etc

If you want another source beyond Stoptech and a 40-years-famous race engineer how bout the editor of Brake and Front End magazine?

Brake Tech Feature: 8 Myths that Could Be Holding You Back from Performing the Best Brake Job: Brake and Front End



article goes on to explain those in more depth
 

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i surely hope i find an answer for the shakes on my es300 ....like as above i have tried every suggestion , brakes complete from and rear-switch whls/tires airp...i think the vibration is in the front, when i finally become to almost a stop i can notice slow to fast action performance in the brakes....(all rotors and calipers replaced) i dont like to share this next with ya having worked in a brake and front end ONLY top notch repair shop for six years ....i felt there was nothing i had not seen with braking problems........well i am humbled at this moment......we need some new fresh top of the line help i guess and some extra luck...i will keep watching this post..
 

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Back from the dead after 8 years!!!

Take wheels off, wirebrush/sand off any rust or debris on the back of your rotors and on the hubs where the rotor contacts. Tighten lugs so as to cinch the rotor against the hub. Install dial indicator against outer rotor surface. Rotate rotor and watch for run-out. Repeat for inner surface of rotor. If you see less than about 0.010, the issue is not the rotors. Look instead at worn tie rod ends, ball joints, control arm bushings, etc.

On my IS300, I chased a "warped rotor" issue for some time. In the end, upgraded #2 caster arm bushings solved issue - but the ES300 is a different car.

Last, I also had the dreaded ABS activation under light braking, approaching a dead stop. After lots of diagnostic work, the issue was weak wheel speed signal at low speed. These cars use variable-reluctance style speed sensors on the wheels. VR sensors are very sensitive to the gap between the toothed "tone ring" and the sensor itself.

To diagnose, hook up an oscilloscope to each wheel speed sensor, one at a time. Do this by back-pinning the connector. Polarity does not matter. Rotate the wheel and look for signal. As soon as you begin rotating the hub, you should begin to see a sine wave on the scope. Amplitude should be at least 75-100mV peak-to-peak. If you don't pick up a signal until you spin the hub faster, you have a weak signal that is dropping out. This makes ABS module think the wheel has come to a stop and thus, the ABS system activates.

The problem could be wheel speed sensor itself, trash on the tip of the sensor, too much gap between tone ring and sensor, or damage to the tone ring.

In my case, I found lots of metal filings/rust/trash on the tips of my rear sensors. The issue, ultimately, was rust on my upright. Rusty metal kinda de-laminates and grows. That growth pushed the stainless steel ring surrounding the tone ring inwards, which made it start to contact the tone ring itself. This caused the tone ring to wear, so it sloughed off particles, which collected on the magnetic tip of the sensor. The direct cause of my erratic slow-speed ABS activation was a poor signal, caused by the wear to the teeth of my tone ring.
 

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thanks so much for time and effort ....the abs makes a good point as to cause......will suely give it a try....terrific
 

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i surely hope i find an answer for the shakes on my es300 ....like as above i have tried every suggestion , brakes complete from and rear-switch whls/tires airp...i think the vibration is in the front, when i finally become to almost a stop i can notice slow to fast action performance in the brakes....(all rotors and calipers replaced) i dont like to share this next with ya having worked in a brake and front end ONLY top notch repair shop for six years ....i felt there was nothing i had not seen with braking problems........well i am humbled at this moment......we need some new fresh top of the line help i guess and some extra luck...i will keep watching this post..
Most likely the brakes were not bedded in properly. If not that, then I would look at the lower control arm bushings....they could be worn out causing the excessive movement when braking.
 

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thanks for reply, the pulse braking off and on at slow speeds mostly was b-4 doing the brakes.....hoping all new components would fix my problem....infact i did as mention neasure the trueness of rotor w./dial .002.......on one inside measure.......????
 
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