Brake dust from pads...

[SRGTD]

Brake dust is made up of both brake pad friction material particles AND brake disc particles - Brake discs for cars are all made of cast iron (except exotic carbon ceramic discs).
Most European cars (including All VAG group) use a low metallic friction material type which is black in colour - so I suggest the brown colour you are seeing isn't brake pad dust. I suggest it is brake disc dust which is iron particles, which will be very hot and embed them selves in the lacquer in your wheels.
this will be especially more prevalent with performance models which use a more aggressive brake pad friction material - which will wear the discs down quicker creating more iron dust.

Makes sense.

@RUM4MO; might be worth investing in some fallout remover, such as Car Pro Iron-X or Valet Pro Dragon’s Breath.

 

[black_sheep]

Makes sense.

@RUM4MO; might be worth investing in some fallout remover, such as Car Pro Iron-X or Valet Pro Dragon’s Breath.

I’ve used the Dragon’s Breath and Iron-X on this contamination too. Like other alloy wheel cleaners (bilberry), removes some but not all.

 

[SRGTD]

I’ve used the Dragon’s Breath and Iron-X on this contamination too. Like other the alloy wheel cleaners (bilberry), removes some but not all.

Using a clay bar may remove any contamination that the iron fallout products don’t. However, with the design of some alloy wheels, claying could be quite time consuming and difficult to get into all those hard to reach areas.

Maybe it’s a case of ‘prevention is better than cure‘ to minimise build up of dirt and embedded contaminants and make it easier to remove. Once any embedded contaminants have been removed, protect the wheels with a ceramic sealant or regularly apply a couple of coats of wax or sealant and weekly washing of the wheels. Check wheels regularly for any future embedded contaminants and decontaminate / protect again as necessary.

 

[black_sheep]

The wheels are currently protected with Carbon Collective Platinum Wheels (2 coats) ceramic coating now and C5 before that, applied when the whole car was ceramic coated.

They are periodically topped up with Poor Boys sealant, but still have this issue.