Brake Conundrum?

[BlkNotes]

Hello members;

I am new to posting in this forum and am looking for some advice.

I recently replaced all 4 rotors and pads on my is300 with aftermarket cross drilled rotors with zinc plating and ceramic pads.

After the job was finished I took the vehicle for a short drive and noticed that there was a rubbing noise coming from the vehicle just coasting and not applying the brakes. The noise became more intense when the brakes were applied. I would describe the sound as a metalic type like the rotor was rubbing. I could not tell where exactly it was coming from.

If anyone has not driven their car for a few weeks and light corrosion builds up on the rotor when driven it makes a rubbing/grinding noise until the rust build up wears off. The noise occurs even when not braking.

On closer inspection I jacked the car up and tested all 4 wheels. They all make this sound. It sounds like the pads are dragging on the rotors. There is slight resitance when I turn the tire but I can still turn it fine. The rotors are zinc plated so I am wondering if the extra coating of zinc could be causing this decrased clearance between the rotor and pad, or could it be the drilled holes?

I lubbed the pins and shims etc.. and retracted all the pistons back prior to installing the new pads.

Could this be normal wear-in process? The car breaks fine. sticky or non-retracting piston perhaps, but would this happen on all 4 wheels?

Any suggestions would be appreciated.

Thank-you

[stufadrummer]

just a suggestion but check the dust shield behind the brakes its real easy to slightly bend them with your hand and that has happened to me just bend them back

[IanH]

Ok. What you have sounds normal.... Let me explain.

All newer disc brakes rely on the play in the wheel bearings to knock back the pads.

My 67 Jaguar has a retraction mechanism that pulls pads back 0.010, but i have neve rseen this on a modern car.

So to test this you need to drive the car at low speed, do left right shakes and stop using the hand brake drum brakes, or coast to a stop where you can jack it up.

you should find the brakes are not in contact.

Only other thing to check is rear discs have been reported to rub at rear inside. remove and Look for bright spots.