Ceramic brake pads - noise?

[cynix]

Hey guys,

A few months ago I've replaced all four warped rotors on my 2005 with drilled/slotted ones, and they came with PowerStop Evolution ceramic pads.
The pads give a medium hissing/grinding noise when braking, especially when they are warm (after a few miles). This doesn't bother me - but what does is that there is a permanent light hissing sound (also audible when brakes are warm) when coasting at a slow speed and when I do not apply the brakes, as if a pad is always lightly touching the rotor. The caliper doesn't seem to be dragging (at least all wheels are uniformly warm - are there other ways to check?). Also, when replacing the rotors/pads I've noticed that calipers do not have the spring clips that force the pads apart (I used to have those on other Toyotas I had before), so I guess that could be the issue - are there any aftermarket options? Or should I just scrap the pads and go get something else?
Your help is appreciated!

---
2005 SE CV V6, 80K mi

[Black Bob]

With no pressure on the brake pedal during driving the pads should NOT be in contact with the rotor at all. Normally the pads should be just far away from the rotor to slip a thin sheet of paper in-between. As you eluded to the constant contact problem is usually found to be a stuck ("frozen") caliper. If that's not it, then that opens the door to a myriad of possibilities--fluid pressure, incorrect rotor/pad thickness from the manufacturer, etc.

Also, I, too, heard rubbing once but it wasn't my pads, I found the culprit to be my emergency brake shoes. The return(?) spring in the rear was shattered from corrosion and the shoes were constantly rubbing. Just something else to check.

[gnegroni]

You might want to check the E-brake shoes or frozen calipers first, but I experienced similar problems since I changed my rear pads to those you are using. I'm thinking the culprit might be incorrect thickness (out-of-spec) pads, but since you also purchased the calipers, I can't say.

What sucks more is that I could have purchased the Toyota OEM pads for the same price I got the PepBoys ceramics (same stuff).