I had my front rotors replaced on my '02 Isuzu ...

I assume you also installed new disc pads.  The disc pads today contain no asbestos, so heat resistance is a problem.  The newer material to contain this heat resistance problem disperses brake dust to an irritiating level.  The only solution is to change the recently installed pads with ceramic pads.  These are a bit more expensive, but they have proven to be a good substitute for asbestos pads.  I hope this helps.

Most brake pads are metallic unless you spring for ceramic.  The brown dust is merely rust from the metallic brake pad wearing down.  This is common, especially during the break in period following service.

Hi,

brown dust on the front rims is the natural bi product of disk brakes