Growing up, our breaker pads had the metal finger that would scrape it's an ∞ better system because all eight pads has a sensor and you'd get the squeek no matter which got low.

3mm is overly generous and I tell my family and clients when the wear sensor trips, to plan within the next couple months or 2-3,000 miles to replace brakes.

I wore mine down to under 2 and they worked find for normal braking but could no longer lock up the wheel so there was diminished power for sure.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)