Quote:
Originally Posted by TurnAround
I've been living the nightmare of the dreaded X5 brake 'chudder' steering wheel shakes for about 4 or 5 years now. I feel like I've tried everything.
Its caused by uneven brake deposits on the rotors and the pads. Deposits are normal, and good. You want the brake pad material to transfer into the cast iron rotors. That's brake bedding. But, this layer has to be even, otherwise you have a 'grab' / 'slip' / 'grab / 'slip' chaos pattern that sets up a vibration with the brakes that transfers to the steering wheel. Replace the pads, massively rebed them in until smoking, or sand them down.. voila.. the chudder is gone for 2 months. .. until the uneven deposits come back. All cars get uneven deposits. Its the darned suspension design of the 5 series. I have two Z3's, both with 'no dust' pads and I've never had a single problem. The suspension arms are shaped differently and come in from more of a side angle. Uneven deposits don't cause vibrations.
On the X I've had the front strut arms replaced (that replaces both sets of front bushings). Made a 15% improvement. Still violent steering wheel shake when braking above 55mph.
I've replaced the rotors, and replaced the Centric Posi-Quiet ceramic pads (near zero dust.. is the attraction to these pads) with Stop Tech Street Performance pads to introduce some bite to clean off the un-even deposits. Same pattern. All great for 3 months, then the F-ing chudder is back! AND.. my wheels are completely covered in brake dust. Worse than factory pads.
I've made the following decision; I'm replacing the rotors one last time, but I'll use slotted and cross drilled in the hopes that it will introduce some 'anti-chaos' pattern for the brake pads. I'm going back to low dust pads. If necessary, I'll replace them once a year.
Another $400 and a weekend lost.
I'm so tired of this, but I don't know what else to do. I love my X5, but I hate the fucking brakes. Blackened trashed brake dusted wheels.. after only 5 days of driving, is unacceptable. But so is massive steering wheel vibration every time I brake above 55.
Any last ditch suggestion welcome.
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I've NEVER seen this problem with the stock rotors and pads. I install them weekly on customer cars without complaint. Yes, they do dust heavily but it's part of the design. The pads are a fairly soft compound which gives the best combination of cold bite and all around performance. The dusting is just part of it.
The idea of the front wheels being "blackened" after 5 days seems a little extreme but I have no idea what type of driving your doing. My 4.6is with roughly 13" rotors and massive calipers takes a couple weeks to really see the wheels darkenening but I simply clean them once a week to avoid this.
I've rarely had good luck with aftermarket pad/ rotor setups on BMW's between squealing, vibrations and erratic performance. If your sure the front end is right and tight I would pony up, get some factor Zinc coated rotors and Pagid pads and just deal with the dusting. I'd much rather have to clean my wheels more often if it meant forgoing the massive vibrations.
-Ben
05-06-2011, 01:13 PM
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