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Old August 28th 08, 07:01 PM posted to alt.autos.bmw
cosmo[_20_]
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Posts: 5
Default E39 Vibration on Braking - help please !

On Thu, 28 Aug 2008 08:48:53 -0700 (PDT), holdgaj
> wrote:

>I have vibration of the sterring wheel on braking on an E39. There's
>no vibrattion through the brake pedal. Just had a diagnosis from a
>garage - "brake discs (rotors) need replacing". On reading the Brake
>FAQ I see that worn suspension bushes can cause vibration of the
>stereing wheel. The vibration is worse at higher speeds. I would have
>thought that warped rotors would be felt through the pedal as well as
>the steerrng wheel. I'm on a tight budget, and don't want to replace
>the brake discs unecessarily. Can someone confirm that warped rotors
>would be felt through the brake pedal ? Or not ? I'd also be
>interested in the difficulty (i.e. cost) of replacing the suspension
>bushes *& which ones need to be replaced.
>
>Its a E39 528i 50K miles.
>
>Any help appreciated


This is general information. I don't know jack about BMWs. On my chevy
van you can feel warped rotors through the brake pedal but not through
the steering wheel and only while braking lightly when coming very
slowly to a stop. There's kind of a side-to-side "swims like a fish"
wobble feeling the last 5 feet before the van stops. The disks can be
turned for $25 each where I live.
A sophisticated car like yours should warn you well before brake parts
start overheating to the point they warp the rotors is my guess. Even
my '88 325 has a dash light that tells you if the pads need replacing.
This kind of heat happens when the calipers are stuck closed from rust
on the slides maybe. Also, filthy brake fluid can have rust in it
which plugs up the return line so the calipers stay partially on. That
makes the brakes drag and then they heat up the rotors. This should be
obvious when you tear down to replace or turn the rotors. Good luck
and happy motoring.
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