rotor cause vibration without braking?

[mikeg299]

So have a vibration coming from the front of my car. My car vibrates and steering wheel shakes while braking. Either my rotors are end of life or I need to re-bed them. I get that part, as I read a great article posted here titled "are my rotors warped?"
But can a brake pad with uneven surfaces cause a vibration while not braking? The vibration gets worse as I go faster. In other words, I'm wondering if the pad is making uneven contact with rotor, thus causing a vibration?

So one thing is clear: I need to replace my front rotors or re-bed them since the car vibrates when braking.

Is it coincidence that I have a brake problem AND a vibration isolated somewhere else? I'm not an expert by any means so please correct any of my assumptions with 'kindness'.

thanks so much for reading my post!

[amancuso]

"rotor cause vibration without braking?"

I have heard this is possible.

[blackxpress]

Yes, it is possible. There's only one way for you to be sure. Do a brake job. Since you know your car needs one anyway, replace the pads and rotors and see if it still vibrates when you're not braking. What do you have to lose?

[Cyrix2k]

yes, and it's pretty common.

[NNY528I]

this is classic symptoms of thrust arm bushing failure. Why on earth after all the times we have addressed this issue do these stupid myths about failed or warped brake rotors continue to be perpetuated?????

First rotate your tires and see if the problem moves to the back. if not then try bedding your brakes again if you want, but I would move to replacement of your thrust arm bushings as this covers the symptoms you have described.

[mikeg299]

Thanks for the response everyone. Looking at OEM Rotors and pads from EAC. Anyone have a preference? OEM, aftermarket? Could use some advise.

Again, much appreciated

signed,
e39ist

[champaign777]

I also believe that rotors/brakes work when you push brake so may have vibration ( i have a bit )
but can't understand how it's vibrated because of warped rotors if you don't use brakes

[Cyrix2k]

disc brakes drag so you don't actually need to press the brakes to have a vibration if you have pad deposits.

[NNY528I]

disc brakes drag so you don't actually need to press the brakes to have a vibration if you have pad deposits.

Not really no, You would have to have some incredible deposits to even notice this.

[Aintfirsturlast]

this is classic symptoms of thrust arm bushing failure. Why on earth after all the times we have addressed this issue do these stupid myths about failed or warped brake rotors continue to be perpetuated?????

First rotate your tires and see if the problem moves to the back. if not then try bedding your brakes again if you want, but I would move to replacement of your thrust arm bushings as this covers the symptoms you have described.

So then, what if you replaced your entire suspension, front and rear,(including thrust arms with HD bushings from eac)
and still had a vibration?

[NNY528I]

So then, what if you replaced your entire suspension, front and rear,(including thrust arms with HD bushings from eac)
and still had a vibration?

try balancing the wheels, try a different set of wheels(swap with a friend) check your bearings also troubleshoot where the vibration is occuring, sometimes driveshaft issues cause vibration a well. is the vibration speed specific or is it general(does it change or occur only at certain speeds) Read up on the issue of brakes and vibration and you will learn a lot. if the issue only occurs under braking then bedding the brakes may be of benfit beyond that brakes are generally not the source of vibrations.

[Cyrix2k]

If you brake hard and remain stopped, it will be very noticeable. It *shouldn't* be an issue on the street, but you never know with the way some people drive. And you certainly don't need "incredible" deposits to notice; disc brakes drag so you'll feel high points... light braking should exacerbate the problem.

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml


A warped brake rotor can also cause vibration even while not braking
http://www.justanswer.com/questions/u29a-2000-chevy-silverado-extended-cab


http://forums.bimmerforums.com/forum/showthread.php?t=501558
^this thread actually covers pretty much everything.

[NNY528I]

If you brake hard and remain stopped, it will be very noticeable. It *shouldn't* be an issue on the street, but you never know with the way some people drive. And you certainly don't need "incredible" deposits to notice; disc brakes drag so you'll feel high points... light braking should exacerbate the problem.

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

http://www.justanswer.com/questions/u29a-2000-chevy-silverado-extended-cab


http://forums.bimmerforums.com/forum/showthread.php?t=501558
^this thread actually covers pretty much everything.


Read your own links there Cyrix. They confirm what I am saying. Rotors are generally not the reason for the vibration and in almost all cases the vibration will only be detectable WHILE BRAKING. there are allways extremes but as a general rule you must apply some force on the brakes to feel any vibration if the problem is deposit induced.

[Cyrix2k]

I'm not saying it is the cause, just that it could be. And I can tell you for a fact that yes, you can feel a vibration without pressing the brakes from pad deposits. Disc brakes drag all the time. It won't be particularly violent, but it will be present.

[xfordtdm]

Not really no, You would have to have some incredible deposits to even notice this.

+1

Check your bushings.


I'm not saying it is the cause, just that it could be. And I can tell you for a fact that yes, you can feel a vibration without pressing the brakes from pad deposits. Disc brakes drag all the time. It won't be particularly violent, but it will be present.


Brake pads don't "drag". "Drag" would be caused by something like a a seized caliper that doesn't let the pad release from the rotor surface. A bad wheel bearing can cause vibration as well as a drag.

If you have a dial indicator with a magnetic base, you can check the runout of your rotor before wasting money changing the rotors when it is not the problem.


I'm not saying it is the cause, just that it could be. And I can tell you for a fact that yes, you can feel a vibration without pressing the brakes from pad deposits. Disc brakes drag all the time. It won't be particularly violent, but it will be present.

Please explain what a brake pad deposit is. I've fixed cars for 2 decades and have never experienced a brake pulsation due to a "deposit".

Your rotors have to have a total indicated runout on the surface of more than .010 inch to feel a noticeable pulsation while applying the brakes.

[mikeg299]

this is classic symptoms of thrust arm bushing failure. Why on earth after all the times we have addressed this issue do these stupid myths about failed or warped brake rotors continue to be perpetuated?????

First rotate your tires and see if the problem moves to the back. if not then try bedding your brakes again if you want, but I would move to replacement of your thrust arm bushings as this covers the symptoms you have described.

You were right....not the rotors. Although breaks much better now. Looking for bushings on EAC tuning. Obviously not called thrust arm bushing, please provide proper term??
thanks!

[TheMatrixz]

They are either called Thrust Arm Bushings, Upper Control Arm Bushing, or Tension Arm Bushings.

[PatrickW]

Thrust arm bushing, also look at the tie rod ends..

[ArmySweitzer]

jack up the car, remove wheel, spin the rotor. Try to notice if it gets stuck at certain points while spinning.

it CAN happen

[NNY528I]

jack up the car, remove wheel, spin the rotor. Try to notice if it gets stuck at certain points while spinning.

it CAN happen

I suspect he just installed new rotors.

[billzcat1]

Yes, badly worn, not warped brake rotors can cause vibrations but not due to deposits or dragging pads, but due to balance! The rotors are balanced from the factory but only when new. As they wear, they slowly lose their balance, just like your tires. I have had a couple different cars where I unexpectedly cured subtle highway-speed vibrations by doing a brake job.

However...if you have significant vibrations you need to look elsewhere such as wheel balance, tire damage, and thrust arms.

[BimmerBreaker]

Not really no, You would have to have some incredible deposits to even notice this.

Seriously... your rotor would either have to be SEVERELY off balance, SEVERELY warped, or with INSANE amounts of pad deposits for vibration while not braking to be present.

Almost guaranteed its something else.