Servicenews article - The brake pads for models with iron brake discs have a high metallic content. That's to ensure high-performance braking under a wide range of conditions. But if the vehicle is parked with wet brakes, the pads and brake discs can rust together, which may cause a clunking or rubbing the next time the vehicle is driven. This is normal for brakes with high-friction pads and iron discs, and doesn't affect brake operation.
