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Rotors warped...again

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Old 05-03-13, 08:05 AM
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Eds98LS
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Default Rotors warped...again

I had my rotors turned back in November but the shimmy doth return.

I think my wheel washes while still hot have caused it. Noticed major steam last week so I'm not really surprised it's back >0

Should I get them turned again this soon? I'm debating new ones but would rather wait until I need pads.
Old 05-03-13, 09:26 AM
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dengman
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strut rod bushing?
Old 05-03-13, 11:22 AM
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timmy0tool
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of course i would have them turned again, that is if they still meet the minimum thickness level.

as for cleaning the wheels while hot, yes they can warp the metal that way.

as dengman suggested check all your bushings and ball joints for play. the vibes could be coming from them under braking.
Old 05-03-13, 06:26 PM
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ajahearn
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Not to be rude, but conventional wisdom is that rotors do not warp. Instead what happens is that they get a asymmetric buildup of brake pad residue which causes the vibration we feel in the steering wheel. This can sometimes be resolved by re-bedding the rotors (follow successively faster short distance stops).
Another thing to consider is that although the vibration may appear to be coming from the front, a buildup problem on the rear wheels can also be felt this way. I've made the mistake of replacing front rotors only to find it was the rear rotors that were the problem. I hope this helps.
Old 05-03-13, 09:00 PM
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Lavrishevo
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Cross drilled and slotted.
Old 05-03-13, 09:09 PM
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ttyR2
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Slotted is good enough. Drilling rotors will tend to create cracks around the holes.

Last edited by ttyR2; 05-03-13 at 09:18 PM.
Old 05-03-13, 11:26 PM
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Hodson
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Originally Posted by ajahearn
Not to be rude, but conventional wisdom is that rotors do not warp. Instead what happens is that they get a asymmetric buildup of brake pad residue which causes the vibration we feel in the steering wheel. This can sometimes be resolved by re-bedding the rotors (follow successively faster short distance stops).
Another thing to consider is that although the vibration may appear to be coming from the front, a buildup problem on the rear wheels can also be felt this way. I've made the mistake of replacing front rotors only to find it was the rear rotors that were the problem. I hope this helps.
Rotors do not warp? It's common knowledge that rotors will warp when you overheat them. All metal does this, you cannot subject it to extreme heat changes and think that it will remain perfectly true and straight.

Check to see if one or more of your calipers might be sticking on, as that could result in permanent braking on one wheel, causing immense heat and large warping of the rotor. It could also be that when you had them machined last, they came very close to the discard and were very thin, and depending on your driving behavior could have also warped them very fast. I don't know if it would be any sort of bushings or anything in your front end if you feel nothing when driving and not applying the brake.
Old 05-03-13, 11:46 PM
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cobalt91
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Over tourqing the wheel studs can also cause warping of the rotors.
Old 05-04-13, 06:28 AM
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python
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Originally Posted by Hodson
Rotors do not warp? It's common knowledge that rotors will warp when you overheat them.
not true..what ajahearn says is true. im not saying he doesn't have issues with front end or calipers..but common knowledge is the rotors don't warp...its pad material transfer
Old 05-04-13, 12:25 PM
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RA40
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The wheel washes aren't helping and do check that they are all lugs are torqued accurately. If the rotors are within spec, have them turned. As well, check the various suspension bushings.
Old 05-04-13, 05:05 PM
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ajahearn
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I chose my words poorly. What I should have said is that irregular pad deposition on the rotor can often be misdiagnosed as warped rotors. Rotors can warp but misdiagnosis is more common.

Turning a rotor simply removes the pad deposition which is why the problem goes away. I've found that a lot of shops won't turn rotors anymore as the thickness just doesn't allow for it.

Certainly a frozen caliper can also be misdiagnosed as a warped rotor. Over tightened lug nuts also.

I replace my rotors when they show bad grooving or are below the minimum thickness specified.

Hope this helps.
Old 05-04-13, 08:55 PM
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Kardon
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I just bought a 98 with a slight wobble when braking from higher speeds, I figured my rotors were warped, now I'm not so sure. What is most common cause of a wobble braking from high speeds? Previous owner said he recently had the rotors turned aswell 0___o
Old 05-04-13, 10:22 PM
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PureDrifter
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Originally Posted by Kardon
I just bought a 98 with a slight wobble when braking from higher speeds, I figured my rotors were warped, now I'm not so sure. What is most common cause of a wobble braking from high speeds? Previous owner said he recently had the rotors turned aswell 0___o
check strut rod bushings for tearing/wear first.

Last edited by PureDrifter; 05-05-13 at 10:52 AM. Reason: strut rods lol
Old 05-05-13, 06:31 AM
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Kansas
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Originally Posted by PureDrifter
check sttrud rod bushings for tearing/wear first.
^^^ I agree. I had the original strut rod assemblies and bushings replaced years at 83,000 miles due to front end vibrations and sloppiness. The car is now at 165,000 miles and the same symptoms are returning. That the strut rod bushings on these cars rarely last much beyond 75,000 miles or equivalent km has been well documented both on Lexus forums and in the automotive press.

Brake rotors on these cars can last "forever". I measured the front rotors on my 00 LS after the brake pads had been replaced and the rotors resurfaced for the second time at just before 150,000 miles and the rotors measured exactly the same thickness as when the car rolled out of the factory in June 2000.
Old 05-05-13, 03:05 PM
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rick1987
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Someone mentioned slotted rotors.

Any recommendations?


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