Z28barnett

You could have been given the wrong pad. If the pad is too shallow then it would not clamp on the whole rotor.

You should be able to see if the pad reaches past the area that shows no wear.

The pad should reach almost to the center of the disk, just short of the bump out where the disk fits over the hub.

You can pull the top bolt that goes to the slider pin in the iron bracket and then rotate the caliper back to expose the pads. Make sure they are installed right.

Spread caliper could be the problem, but it might be something easier.

GM does not recomend turning disks unless the the surface has groves that exceed .030, or if you have warping problems.

Z28

Z28

frmula1

no they are the right pads... and they are installed correctly (by me )

and keep in mind... it didn't do this after we change the brakes... they were working normally for weeks before this happened

lateapex

The only reasonable explanation for his symptom is spread calipers. If the car is not road raced or driven a lot in the mountains, it is not a problem which HAS to be fixed at this point. The more he drives it, the more the top of the pads will wear down (at an angle) until he has full pad/rotor contact. Once the caliper has spread, it cannot be repaired. The aluminum has fatigued. If you were to put the caliper in a vise and pinch the caliper faces back to parallel, they would spread again almost immediately, but worse than they were before.

After the pads have worn to a complimentary angle and he has complete rotor contact for normal driving, there will not be even pad pressure on very hard stops because the caliper will flex even further, dynamically. So the pads will wear at an even more severe angle than the caliper has spread statically.

In other words, he will waste a good portion of his front brake pads until he gets calipers where the caliper halves are parallel. If he doesn’t want to have the backing plates score the rotors, then he will probably have to replace the pads when over 50% of the material is still left on the bottom (inner portion) of the pads.

You may not have noticed the problem immediately, but it was there unless he has done some VERY serious braking since the brake job. Another thing that affects the severity of the problem is the coefficient of friction of the pads. Ceramic street pads are known for having a low friction coefficient. Therefore, you have to press the pedal harder, and the increased hydraulic pressure forces the caliper faces further apart. Using a high coefficient pad in the first place can minimize caliper fatigue since under all conditions, the caliper is being flexed less.

Deimos

How did you determine that they were not warped. Did you use a dialk indicator, take rotor measurements to measure for lack of parrellism. Hopefully you relubed the slide pins very good. Also if the rotor is only making contact depending how far up it is that is normal. You always want to check the spec of the and turn them if you have enough rotor left. Give better matting and makes sure it is making proper contact.