Newly Machined Rotors Making Thumping Sound
If you just had your rotors cut or machined and installed them with new pads but you hear a rhythmic thumping sound, likely it’s a rough finish on the rotor. The rough finish on the rotor acts like a screw to draw up the pads. The thump comes when the pads snap back to their original position.
Rotor finish is critical for proper brake operation. If they look lie an old vinyl record you can try to sand the rotor surface with 180 grit sandpaper to remove any ridges that grabbing at your pads. You may have to re-machine or cut them at a very slow speed.
likely that a new will cost less and save you time. PowerStop’s rotors come with a beautiful non-directional cross-cut finish that will perform well with those new pads.
Don’t Just Stop… PowerStop!
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