bimerguycw
10-17-2007, 08:06 PM
Sorry, this is a detailed help request before I just start replacing damaged parts.
I have had smoking from both rear brakes today after noticing that the car felt like the car was dragging from idle the parking brake was still released to start driving (And no the hand brake level was not up) and then they apparently got hot enough in the travel distance about 10 miles to begin smoking at a stoplight and I had it towed knowing from the smell and smoke that it was binding.
While waiting for the tow truck I checked the rear brake binding again after sitting with the parking brake off about 40 minutes later and the car could move freely with idle speed with no binding as before.
By the way, these rear rotors and pads were new about 6000 miles ago and never had this symptom until now.
Once I got the car towed home the rear brake binding was still not there and I removed the wheels to rotate the wheels and they rotated freely. Visually checked caliper piston sticking or parking brake binding and neither had a problem when using them while car jacked-up and rotating while trying the parking brake or calipers with someone in the car...but obviously not hot enough as before. The pedal and hand brake would both slow/stop the wheel rotating evenly when checking. No catch places around the wheel rotation during this test just smooth rotation and braking.
The advice I need is in my findings when I removed both rear rotors and found:
1) The rotors' parking brake shoes inner surfaces where bluish-purple-black on 80% of the contact area(Over-heated)
2) The parking brake shoes had cracks across them in about 4 places but thickness even and a little less than 1/4" thick.
3) The disc rotor surface was overheated looking but not nearly as much bluish coloration as the inner shoes surface.
4) The 6 mo. old disc pads were overheated and looked like a rough grinder was used along the flat surface(rather than smooth, glazed surface). And the paint was peeling of course from the heat.
5) The pads thickness was 90% remaining and even thickness.
This is the same and even for both rear wheel brakes. I had noticed that the parking brake light flickered on a few times over the past several weeks but never stayed ON and no dragging noticed at that time; if that has any value to the likelihood that the parking brake needed adjustment and cause dthis problem. I thought the Parking Brake light was just triggered for the hand lever being up and making contact regardless of brake adjustment.
Obviously, I will have to replace these rotors, discs, pads, shoes and not willing to do this until I know the cause as it may happen again so please add your experiences from these symptoms.
I'm unsure which caused the problem:
1) A sticking/binding parking shoes( Do these require greasing/lube in the cable assembly over time?)
2) A binding/sticking caliper pistons(ususally 1 vs. both at the same time.
3) A master cylinder flaw in this 1/2 of the hydralic circuit
4) A combination of these like a binding parking brake shoes and then indirectly overheating the rotor to then bind the pads while driving at speed to add more overheating.
5) Or something else that control the rear set like ABS.
I have had smoking from both rear brakes today after noticing that the car felt like the car was dragging from idle the parking brake was still released to start driving (And no the hand brake level was not up) and then they apparently got hot enough in the travel distance about 10 miles to begin smoking at a stoplight and I had it towed knowing from the smell and smoke that it was binding.
While waiting for the tow truck I checked the rear brake binding again after sitting with the parking brake off about 40 minutes later and the car could move freely with idle speed with no binding as before.
By the way, these rear rotors and pads were new about 6000 miles ago and never had this symptom until now.
Once I got the car towed home the rear brake binding was still not there and I removed the wheels to rotate the wheels and they rotated freely. Visually checked caliper piston sticking or parking brake binding and neither had a problem when using them while car jacked-up and rotating while trying the parking brake or calipers with someone in the car...but obviously not hot enough as before. The pedal and hand brake would both slow/stop the wheel rotating evenly when checking. No catch places around the wheel rotation during this test just smooth rotation and braking.
The advice I need is in my findings when I removed both rear rotors and found:
1) The rotors' parking brake shoes inner surfaces where bluish-purple-black on 80% of the contact area(Over-heated)
2) The parking brake shoes had cracks across them in about 4 places but thickness even and a little less than 1/4" thick.
3) The disc rotor surface was overheated looking but not nearly as much bluish coloration as the inner shoes surface.
4) The 6 mo. old disc pads were overheated and looked like a rough grinder was used along the flat surface(rather than smooth, glazed surface). And the paint was peeling of course from the heat.
5) The pads thickness was 90% remaining and even thickness.
This is the same and even for both rear wheel brakes. I had noticed that the parking brake light flickered on a few times over the past several weeks but never stayed ON and no dragging noticed at that time; if that has any value to the likelihood that the parking brake needed adjustment and cause dthis problem. I thought the Parking Brake light was just triggered for the hand lever being up and making contact regardless of brake adjustment.
Obviously, I will have to replace these rotors, discs, pads, shoes and not willing to do this until I know the cause as it may happen again so please add your experiences from these symptoms.
I'm unsure which caused the problem:
1) A sticking/binding parking shoes( Do these require greasing/lube in the cable assembly over time?)
2) A binding/sticking caliper pistons(ususally 1 vs. both at the same time.
3) A master cylinder flaw in this 1/2 of the hydralic circuit
4) A combination of these like a binding parking brake shoes and then indirectly overheating the rotor to then bind the pads while driving at speed to add more overheating.
5) Or something else that control the rear set like ABS.