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warped rotors would be my guess. sounds like the exact problem, you could shake down the car to make sure all the steering components are tight, but i would start with the brakes. it shouldn't be to much of a tire balance issue if it's just at high speeds, but you could check the wear of the tires also.
 

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Warped front rotors no doubt. Some part stores will turn them for about $10 each. Thats what i did to mine. Smooth as can be now.
I have this issue too. My steering wheel doesn't shake violently but enough to get me a lil worried. What do you mean by turn them?
 

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Incorrect bedding and brake pad break-in will cause this. Next time you get new brakes pads and rotors, be especially easy. The new rotors need to be exposed to heat and cooling slowly and the pads need to bed themselves into the new rotors. It is best to`machine the original rotors you had, if you must buy new rotors. Use OEM pads with OEM rotors.
 

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I had this problem.

I just recut my front rotors and resufaced my brake pads. This solved my shimmy problem for now, but I noticed play in the rack and pinion's inner tie rods. I know this will magnify any play the steering system. I'll start pricing around for a rebuilt unit. Hope this helps.
 

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Warped rotors are not exactly correct. Brake pad depositions on the rotor surface are responsible for wheel judder when braking. Depositions occur when hot brake pads are held against the rotor and create deposition spots. You can actually see the imprint of your brake pads if help there long enough.

I had this same problem and had the opportunity to switch to Stoptech Slotted rotors and Axxis Ultimate Brake Pads with the Stoptech SS brake lines.

Immediately all judder stopped, and now the braking is much more precise and "joltful". I recommend slotted rotors because they tend to resist brake pad deposition to a greater degree than blank or cross drilled for a reason i don't know.
 

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At the minimalist.. change your front rotors and pads. Regardless if its warped rotors or pad depositions. My best guess is the warped rotors.. which means you should change your brake pads as well. Keep in mind if excess vibrations are neglected.. it may cause more damage to other components.

Kudos,
Jay
 

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He already said he has replaced all of his pads. No need to do it again. After the rotors are turned the pads should bed in after a few miles or so.
 

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Uneven pad deposits on the rotors...........Warped rotors.........whatever. Getting the rotors turned or ridding the rotors of the pad deposits should solve this probem. Straight from the Stoptech article: "The only fix for extensive uneven deposits involves dismounting the discs and having them Blanchard ground - not expensive, but inconvenient at best."
Is this not what is done when the rotors are "turned"? I got my rotors turned and problem solved. The shimmy went away.
 

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Uneven pad deposits on the rotors...........Warped rotors.........whatever. Getting the rotors turned or ridding the rotors of the pad deposits should solve this probem. Straight from the Stoptech article: "The only fix for extensive uneven deposits involves dismounting the discs and having them Blanchard ground - not expensive, but inconvenient at best."
Is this not what is done when the rotors are "turned"? I got my rotors turned and problem solved. The shimmy went away.

Yes... but

A) The article also lists several, better, solutions if your deposits are not extensive and/or haven't been there long that do NOT require shaving precious rotor material off with a grinder.

and perhaps at least as important

B) It explains why the problem happens, and how to avoid it in the future.


Knowing WHY you're having a problem is often at least as important as knowing how to get rid of the problem, assuming you don't want to have it again soon after.
 

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He already said he has replaced all of his pads. No need to do it again. After the rotors are turned the pads should bed in after a few miles or so.
Then he should at least change his rotors. Lets just say in this case, the culrpit are his warped rotors. It wouldn't matter how new your pads are because under brake load.. the pads are unable to make 100% contact with the rotor's surface.. which in returns causes the pads to skip along the surface. This is why under higher speeds.. you feel a more aggressive shaking while low speeds are almost, if anything, unnoticeable. As far as the rotors "breaking-into" the pads.. that's doubtful.

The only other reason why it would rumble that I can think up of is.. bad lower ball joints w/ bad wheel bearings w/ bad toe ends or a crazy combination of everything. But if that was the case.. the rumbling wouldn't just occur under braking.

Kudos,
Jay
 

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Yes... but

A) The article also lists several, better, solutions if your deposits are not extensive and/or haven't been there long that do NOT require shaving precious rotor material off with a grinder.

and perhaps at least as important

B) It explains why the problem happens, and how to avoid it in the future.


Knowing WHY you're having a problem is often at least as important as knowing how to get rid of the problem, assuming you don't want to have it again soon after.
Excellent article thanks for the link.

Comments.
To start this process you have to not bed in the brakes or exceed the hi temp limit.

He did forget the brake squeakers.

Blanchard grinding. While this is a common shop tool ( the ones i have seen are big and very expensive) I have never seen one used in a brake shop, and the marks are very characteristic for this type of machining.
So you may see this on new discs or in a race shop but not on street turned discs.

The typical rotor turning is just that, turned on a lathe specially made for the purpose.

This doesn't explain my Subaru legacy. Purchased new, bakes start pulsing within a few months.
Turn the brakes, pads left....Ok now its smooth. First Rain, pulsing returns
Repeat
repeat again. (doesn't rain much in Albuquerque)
etc until Turned the rotors to minimum thickness !!!
Replaced rotors and pads under warranty (OEM of course.)
never an issue again. I had that car 10 yrs on those replacement rotors !!

This may however explain the pathfinder brake issue.
when cold, brakes were smooth. Around Dallas you would feel a light pulsing when driving around in traffic.
In the mountains in Colorado it was so bad I was using the gears to slow the car as much as possible because the pulsing became a grabbing.
return home, Stealership couldn't find anything wrong.
Symptoms return to as before the trip.
Didn't get worse with the mountains, but maybe the transferred pad material wore down ?
Or rotors were warping with the heat ??

But replacing with slotted rotors and Metalmaster pads fixed it good !!!
 
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