At 40,000 miles a GM Dealer turned the rotors and drums and installed new Raybestos Ceramic Pads and Raybestos brake shoes. After about 10,000 miles we started getting steering wheel pulsing when braking.
It slowly got worse and another GM dealer installed New Rotors at about 80K. At least 95% of the pulsng went away, it was still there, just a little. Steering heel pulsing varies from not to bad when you first start out to smetimes very bad after 20+ miles of moderate braking. An independant shop checked Run Out on both Rotors, one was 0 the other 2 thousands. He said the ceramic padsstill looed good, the brake drums and shoes also had very little wear. He saw possibly a little exess baring play and adjusted. Problem is still there. He also checked tire preasure and balance, checked all front end parts for wear. All looked good, we give up, what should we try next. Also the pedal does not pulse when brakes are applied. Shimmy sometimes can get bad enough to pull vehicle to the right, this happens occasionally.
I had a 1999 Silverado PU that when you applied the brakes lightly 5-6 times and than applied heavier the truck would shimmy violently The dealer found a bad master clindar proprtioning valve causing the right front disk brake to grab because it did not release properly. We changed the Master Cylinder and have not had any furhertrouble in 60K miles.
This is my wfes vehicle and I need to fix the problem, she is not hard on brakes. She has actually got 100K mles on pads and shoes. She does not drive 2 footed.
I'm leaning towards a bad master cylinder,but can't seem to rule out a bad caliper.
Need help.......Louie
It slowly got worse and another GM dealer installed New Rotors at about 80K. At least 95% of the pulsng went away, it was still there, just a little. Steering heel pulsing varies from not to bad when you first start out to smetimes very bad after 20+ miles of moderate braking. An independant shop checked Run Out on both Rotors, one was 0 the other 2 thousands. He said the ceramic padsstill looed good, the brake drums and shoes also had very little wear. He saw possibly a little exess baring play and adjusted. Problem is still there. He also checked tire preasure and balance, checked all front end parts for wear. All looked good, we give up, what should we try next. Also the pedal does not pulse when brakes are applied. Shimmy sometimes can get bad enough to pull vehicle to the right, this happens occasionally.
I had a 1999 Silverado PU that when you applied the brakes lightly 5-6 times and than applied heavier the truck would shimmy violently The dealer found a bad master clindar proprtioning valve causing the right front disk brake to grab because it did not release properly. We changed the Master Cylinder and have not had any furhertrouble in 60K miles.
This is my wfes vehicle and I need to fix the problem, she is not hard on brakes. She has actually got 100K mles on pads and shoes. She does not drive 2 footed.
I'm leaning towards a bad master cylinder,but can't seem to rule out a bad caliper.
Need help.......Louie
Feb 13, 2009 at 2:38 PM