回複：各位達人請教,我新換的刹車係統

The symptom you described appears to be a minor thing - the shriek noise is coming from the surfaces between rotor and brake pads, particularly when a pad was newly changed. It doesn't pose a safety threat though. To get rid of it, go buy a bag of brake paste (I think it is called brake noise silencer) for 99 cents or $1.99 (I forgot exactly but some brake pads come with a bag of that), take brake pad out, spread the paste at the back of brake pad where the piston touches the pad. Remount the brake pad and the noise will go away.

The shaking of steering wheel during braking is caused by uneven rotor surfaces, or rotor(s) being warped. If brake pads surfaces are uneven, this symptom could arise too. This typically happens on older cars with high mileage, on which rotors had been worn severely. When new brake pads were put on, the outer ridges make pads sitting unevenly. Normally shops will take the rotor out either re-surface it (provided the thickness allows) or replace it with a new rotor (material is inexpensive - about $15/piece, changing by pair).

Hope this helps. Good luck!