I have had the rear brake pads (ceramic) and rotors replaced on the rear of my '04 coupe. What I have noticed is that the rears dust way more than the fronts. The fronts, I never did replace or turn the rotors, I just replaced the pads. This is really odd, how come the rears dust up in a couple of days and the fronts stay pretty much clean for a week? I don't let the car get dirty past a week so I can't say how much time does it take for the fronts to get dirty. These pads are ceramic as far as the manufacturer is concerned - CarboTech

 

Measure the coefficient of friction and durometer hardness between the two pads.
Make sure the slide pins are properly clean and lubricated.

 

I know the slide pins were cleaned and lubricated, but the coefficient of friction and durometer hardness, I am sure not many people would do.
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