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I have a set of Brembo Slotted rotors installed on the front for about 3 months now and I have the PorterField T1 S break pads... I have no problems with them exactly, matter of fact my breaking distance is better than ever... but when I'm on a slow roll like 30MPH and steps on the brake to slow down at about 10MPH and slower it seems like the car makes this unsteady stopping motion, the car makes a back and forth stopping motion... maybe when the slot on the rotors hits the pads is when... maybe makes the car have an unsteady deceleration... but on sudden stops it doesn't make this weird deceleration motion... only when applying less pressure on the brakes... so this is normal right?