I've had my new P for about a month and have detailed the heck out of it ever since I took delivery but I noticed for the first time yesterday after washing it (and a spirited drive) a brown powdery substance inside the wheels. It wipes off easily if that helps. Anyone know what it might be?

 

It is a combination of iron from your rotors and small particles from your brake pads. It is created by using your brakes, avoid using them to keep your wheels clean.

 

 

Rust from washing the rotors gets scrubbed off when driving and combines with brake pad dust - just wipe it off, no worries. Or blow dry the rotors after washing - could help a bit.

 

Lol... Perfect solution to get rid of brake dust for good.

 

Coming from the tech guru, it sounds like we are going down the road to success!