I have a 94 Accord EX Wagon (180k miles) which has developed brake judder when slowing from speeds above 50mph. This also happened about 5 years ago. At that time I had the discs machined and together with new pads the issue was resolved. Since then I've only added another 30K miles and am wondering if this time the issue may be related to the ball joints.

Specifically, the upper left ball joint has a split rubber boot and can be heard "chattering" when driven over a rough surface. My assumption is that means it has some play or movement. Could this be the root cause of the brake judder? I also read that the tie rod ends could have a similar effect but I can not feel and play in them.

Thanks for any advice.

 

Judder??

 

In case it isn't clear, Brake Judder refers to a vibration felt through the steering wheel when the brakes are applied.

 

Is it likely that the vibration is due to the worn upper ball joint?

 

No. Your brake rotors likely need machining or resurfacing.

"Warped" rotors is misleading. What happens with rotors, especially cheap ones is heat. When the brakes get hot enough, and hot spots are formed this heat alters the metallurgy of the rotor. Causing some parts to be harder than others. This creates uneven wear that you feels as vibration when you apply the brakes. Often times machining the rotors will only remove the uneven wear, but not the altered metal. And so the pattern begins again. See it over and over again here in AZ, the summer heat eats brakes alive.

 

If you had your rotors machined 5+ years ago to resolve a brake "judder" and you've added 30k then they are likely below minimum thickness and it most likely needs new rotors. I have heard the term brake "judder" as well as "shutter" and they both refer to a warped rotor that causes the brake pedal to pulsate along with a shimmy in the steering wheel. Hot spots on the rotor can cause the pads to grip harder in some areas than others, resulting in un-even wear and a slight pulsation. An improperly prepped hub and improper wheel torque can cause a warping of the rotors under heat as well, resulting in a more violent steering wheel shimmy and moderate pedal pulsation. Though in your case, your rotors are mounted to the back of the hub and thus wheel torque is less crucial.

If your upper ball joint has a torn boot then it is only a matter of time until moisture and dirt enter the ball and socket, eating metal away until it clunks or breaks. If you have any play whatsoever in your upper ball joint, replace it... immediately. If this lets go while driving it can be a bad accident, even if you remain in control you'll likely need a new fender and tire along with your new upper control arm/ball joint. It all depends on how bad this brake judder is. Is it mainly the steering wheel that is shaking? Is it the pedal pulsation more than anything? Or is the whole car violently shaking when you brake and you can't really tell?

Either way, replace that upper joint (or entire arm), it is dangerous and can most certainly cause a vibration under braking though it is not as likely as a warped or un-evenly worn rotor. Replace that first, then see what your dealing with. If it solves the whole problem then great! If it makes the vibration slightly less intense then you will need rotors as well and the upper ball joint was the instigator of the brake wear. Lastly if you replace the upper ball joint and it has absolutely no effect on the vibration, then you need rotors and know that you needed the ball joint anyway.

 

Like AccordVT said - get the ball joint fixed ASAP.

As for the brake 'judder', generally if you feel the steering wheel shimmy it's the front rotors, if you feel it through the chassis then it's the rear (though I don't think they used disks in the rear of yours).

If you get 50K miles out of new rotors before they are machined, you can bet the resurfaced rotors will not last as long as they did when new - they will be thinner and will not dissipate heat as well, so the same thing that killed them the first time will happen again, just sooner, and they are also more likely to warp.

 

Thanks for all the helpful input and suggestions. To answer AccordVT's question, the vibration is felt mainly through the steering wheel, nothing through the pedal.

I actually tried to replace the upper ball joint but ran into difficulties with the aftermarket part. The distance between the 2 mounting studs (connected to the rubber bushings) was off by 3 or 4mm.

Can anyone recommend a reliable supplier for aftermarket suspension parts? If the forum does not allow this, perhaps you could PM me?