[scusswold]

Hi all,

I've surprisingly got warped brake disks with the car only having done 8,000 miles from new. I can't tell yet if they are front, rear or both as I only heard it today at 5mph - the sound echoing off a wall...

Is this type of thing covered by the warranty due to the mileage? Car registered in Sept 2016 and has the M Sport upgraded brake kit.

I'm sure I've read threads on this but can't remember the outcomes?

Thanks

[teaston]

It's extremely unlikely to be warped discs, they are a bit of a myth! Much more likely to be uneven pad deposits:

http://www.mossmotors.com/SiteGraphi...ake_discs.html

[djcowlin]

Are the disks heavily corroded? I had to replace the front disks on my 330d at about 15K miles due to corrosion - the car had been standing a fair bit over the winter months.

[scusswold]

No corrosion, the disks are still looking like new. They just make a 'swish' sound with each rotation, which you can hear at low speeds. The car hasn't been left standing.

The noise stops when you brake.

[ronime]

Any judder through the brake pedal?

Any unusual road noise at or approaching motorway speeds?

[Watsey]

Are they plain, slotted or drilled ?

Slotted discs tend to make a thrumming noise when brakes are applied. Drilled can make a hollow whistling sound.

Unless there's vibration coming through the brake pedal or the suspension it's unlikely that the discs are warped.

[scusswold]

No pedal tremor at all and no unusual noise apart from the low speed stuff. The disks are the plain BMW factory performance disks. I'll have a closer look hopefully tomorrow.

[Tengocity]

I'd be astounded if the brake discs were warped!

Quite a few of us have tracked our cars with standard discs and no one has managed to warp a disc despite putting massive heat through them.

Groaning, fading, smoking, and grumbling... yes! But not warped discs.

[scusswold]

Ok that's reassuring. I've not really pushed the brakes hard at all either, so hopefully just poor terminology on my part!

[GEP77]

It's highly likely that it's something fairly innocuous rubbing against either the disk or the wheel. If the car was older it could be a wheel bearing, but again highly unlikely on such a young car.

[Canary_Yellow]

I think mine make the same noise.

A metallic sounding gentle rubbing noise when I first pull away. I can only hear it with the windows down and because I go through a sort of tunnel immediately as I leave my parking space.

The sound is gone when I go back through the tunnel on the way home even if only a 5 min journey.

I haven't been worried about it (should I be?), but curious as to what it might be.

[Craig-SM]

Originally Posted by teaston

It's extremely unlikely to be warped discs, they are a bit of a myth! Much more likely to be uneven pad deposits:

http://www.mossmotors.com/SiteGraphi...ake_discs.html

This ^

Try and find a quiet stretch of road and do some hard stops. You may need to repeat 5-6 times before it cleans off. You need to get some real heat into the discs to get the pad resin off.