Concur Bill. Yaleh - these are brand new pads with new rotors?
So, a couple of things to consider:
1. new pads should be "bedded in" according to the manufacturer's recommendation. Simply, the pads need to be worn down a bit to get good even contact with the rotors. Usually, it involves about half a dozen medium stops from 30 - 0, drive 10 minutes to cool. 3 or 4 hard stops from 50 -0. Drive 10 minutes to cool...that warms them up and mates them to the rotor surface. I don't buy the "drive moderately" when every other pad manufacturer recommends a specific procedure. The goal is to set up good contact and to deposit a thin layer of pad material on the rotor (the transfer layer) and that takes moderate heat achieved under controlled conditions to maximize the effectiveness of the pads.
2. When you put new pads on the car, the rotors should be replaced. They can be turned, but it's often the case that the rotors don't have enough thickness above minimum to be turned and re-installed. If they haven't been turned or replaced, that complicates the bed in because the rotors are not flat, and the pads are...and you need a clean surface to build that transfer layer. Sounds like you've got new rotors, though, so...
3. The dragging could be because the caliper isn't fully retracting. There are a few causes for this. First, ensure that the springs are on correctly (and they often aren't...search the threads for pics). Next the caliper pins should be lubed but NOT with petroleum grease, which causes the seals to swell and bind the caliper, it needs to be silicone based. Finally, if the caliper seals are sticking in the bores (corrosion), then the caliper won't retract fully.
4. It happens sometimes that a rock or piece of debris gets lodged in the pad - do you see a groove starting on the rotor surface?
5. Is this sound coming from the front or rear? Are you sure the parking brake is not dragging?
Finally, a good practice is to flush the brakes (replace the fluid) every two years, or when you replace the pads. Fluid is always absorbing moisture from teh atmosphere, this practices will ensure that the calipers and other components don't suffer internal corrosion from old fluid and ensure that the brakes perform under severe use (like mountain driving) because water lowers the boiling point of brake fluid...won't fix your rubbing sound...but since we were on the subject of brake maintenance...
Last edited by Astro14; 07-19-2011 at 04:26 AM.
2006 Corolla (kid's car - 165K, Eco Contacts, Castrol Edge 5W30)
2005 MB S600 (84K, Michelin AS3, M1 0W40)
2002 V70-XC (201K, AltiMax RT43, Pennzoil Ultra 5W40)
2002 V70-T5 (179K, IPD bars, Bilsteins, Conti PureContact, Mobil 1 0W40)
1992 MB 300E (Sportline - 160K, Yokohama Avid, Castrol Edge 0W40)
1990 4-Runner (V6, 4WD, mild lift - 257K, 31" BFG AT KO, Castrol 10W40)
1932 Packard Sedan (straight 8, dual sidemount spares, original paint and interior, Shell Rotella 15W40)