[SkyJawa]

If you get them nice and hot then stop with brakes applied for a length of time you can warp them quite easily.

[TomJ79]

I had this recently...5 year old F31, 60k. Had a major service recently and got them to check it; discs are worn in parts. Still got life left in the pads so gonna swap them out when it's time to do the pads. Just can't afford it before Chrimbo!

[JamesStam]

Thanks for your replies, all. Very helpful indeed.

[Jimbob335DX]

Originally Posted by RobUK

Would tyres be a likely cause if the problem is only felt when braking?

Funnily enough, I was a bit of a doubter myself, but its due to increased load on the front axle under braking. The tyre wall is strong enough to maintain the smooth ride we experience under non braking conditions, but any damage to the side wall is amplified once the braking process begins. The side wall flexs, with the added force of braking and where the damage has occured (in my case it was, pot hole or even ramps at road works), the additional flex in the tyre wall, at the weakened point, causes that tell tale wobble under braking.

It can also happen around certain turning conditions, where excess load is placed on the affected tyre. There was one corner in particular on the A66/M66, where the right front tyre is seriously loaded at speed and I could always tell the front tyre was damaged. On previous cars I less concerned about tyre quality and would normally replace a cheaper tyre with cheaper tyre, as opposed to quality for qualities sake. There is a clear difference between side wall structure, and value of tyre.

Not sure if the OP has had the car checked/diagnosed yet, We shall see when they post back.

Mines having it brakes done/replaced today, at 36K, but I never noticed any sort of wobble and I am just shy of the service point warning by 300miles.

[RobUK]

Originally Posted by Jimbob335DX

Funnily enough, I was a bit of a doubter myself, but its due to increased load on the front axle under braking. The tyre wall is strong enough to maintain the smooth ride we experience under non braking conditions, but any damage to the side wall is amplified once the braking process begins. The side wall flexs, with the added force of braking and where the damage has occured (in my case it was, pot hole or even ramps at road works), the additional flex in the tyre wall, at the weakened point, causes that tell tale wobble under braking.

It can also happen around certain turning conditions, where excess load is placed on the affected tyre. There was one corner in particular on the A66/M66, where the right front tyre is seriously loaded at speed and I could always tell the front tyre was damaged. On previous cars I less concerned about tyre quality and would normally replace a cheaper tyre with cheaper tyre, as opposed to quality for qualities sake. There is a clear difference between side wall structure, and value of tyre.

Not sure if the OP has had the car checked/diagnosed yet, We shall see when they post back.

Mines having it brakes done/replaced today, at 36K, but I never noticed any sort of wobble and I am just shy of the service point warning by 300miles.

Actually that makes sense, I had forgotten about the change in tension/torsion/forces on the sidewall during braking. I suppose technically the same would be possible during rapid acceleration although perhaps less noticeable for other reasons.

[JamesStam]

Afternoon all,
Just a quick update.
I took the vehicle to a local independent BMW specialist who checked it over.
The long and short of it is that he can't find the issue but suspects it's the discs and/or pads.
He had the car up on the ramp and also ran both front and rear on the rollers but still couldn't find the issue for definite.
He said it may slightly less noticeable today because it's so cold (it is less noticeable) and therefore said it's not worth running a dial test because that would probably not pick up the issue either.


Anyway, he said to report back to the dealership and see what they say.

If they don't agree to have it done, then I'm likely to buy the parts myself.
Garage said the fronts would be 1.5hr labour and the rears (if needed) about 2 hrs. Sounds reasonable.
He recommended OEM parts or Pagid.

On that note, does anybody recommend any brake disc/pad manufacturer?

I don't drive hard or fast. Very average.

The car is a 320 ed business edition / 2015.

Regards,
James