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Stupid question but I thought when a handbrake is applied it only works on the rear discs, is this true of the M5?

My car is in again for the brake shudder issue and they are asking me if I leave the car standing with the handbrake applied for a long period of time because Im guessing they are seeing signs of deposits on the discs.

I use it daily but when I park it up it is on a slight slope so I will come to a stop and apply the handbrake (sometimes I drive in, sometimes I reverse)

If this was cause deposits on the discs surely this would only be on the rears? When I come to a stop the brakes would only have seen mild use.

Could it be the pad carriers not pulling them back enough? Im getting really fed up with this
 

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Rear only.

Are the discs within tolerances ?

Also some people claim that discs might get warped if you keep the brake pedal applied for a long time (at standstill) - if the discs are very hot when you stop the car - whether this is true or not I don't know (But that's not an issue in your case).

Most likely, with our weather here in Europe, you'll have rust/deposits because the brakes are not used enough - but are you sure it's the rear discs ?

It could very well be some of the bushings in the front suspension that has given up - or is close to giving up, do a search on 'shimmy', and a lot answers will pop up
 

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Discussion Starter #3
I've had new reaction bushes. The disc are just within tolerance. On my way there now to see what they have found
 

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Mine is a 2000 and on my car the parking brake is a drum setup inside the hub part of the rear rotor. I don't understand why they would be looking at the parking brake for your problem. Maybe it is seized a bit. Parking brake is completely separate to the rear brakes the only part they share is the rotor/drum. I would ask them why they ask?
 

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That sounds like a load of BS. Your parking brake should not leave deposits on your rotors that would cause vibration because it's a drum setup inside the rotor hub. I would apply the parking brake lightly as you drive down the road for a few seconds to clean off any deposits that might be there just to make sure but I don't think it will have an effect on your problem.

Most likely it's bushings or pad deposits from improperly bedded pads or debris. Re-bed your pads and drag the parking brake as I mentioned and see if that takes care of the problem. It is very unlikely that it's your parking brake or that your rotor is warped.
 

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In some cases where you are using a performance pad, light braking will create pad depsosits and shuddering. I have a customer with an E46 and Brembo's that comes in about twice a year for shuddering. We install a set of Hawk Blues and drive the bejeezus out of it... the extra abrasion of the race pads cleans the rotors and voila the problem is gone.
As was pointed out before your e-brake has nothing to do with pad deposits or rotor shudder. Overtightening the lug bolts will cause a shake too.

Do you feel it in the brake pedal? If not then it's more likely a front end problem.
 

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I would run far away from whoever is doing that "service" work. The parking brake is a drum brake.
 

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I would run far away from whoever is doing that "service" work. The parking brake is a drum brake.
Indeed, scary stuff!
 

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Stupid question but I thought when a handbrake is applied it only works on the rear discs, is this true of the M5?

My car is in again for the brake shudder issue and they are asking me if I leave the car standing with the handbrake applied for a long period of time because Im guessing they are seeing signs of deposits on the discs.

I use it daily but when I park it up it is on a slight slope so I will come to a stop and apply the handbrake (sometimes I drive in, sometimes I reverse)

If this was cause deposits on the discs surely this would only be on the rears? When I come to a stop the brakes would only have seen mild use.

Could it be the pad carriers not pulling them back enough? Im getting really fed up with this
When do you feel the shudder, after 10~20mins of driving?
Shudder feel in steering wheel?
Once it starts a sharp dab on the pedal only makes it worse?
Happens worse around 45~50mph?
 

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When do you feel the shudder, after 10~20mins of driving?
Shudder feel in steering wheel?
Once it starts a sharp dab on the pedal only makes it worse?
Happens worse around 45~50mph?
exactly, shudder could be from many things, rims bent, wheel balance, suspension NQR
high speed / low speed / cold vs hot - any other clues?
washing wheels and leaving them without drying the discs can cause some deposits
as said above - run from the service guys, fast....
 
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