Chevy Blazer Rear Brakes Locking Up
Vehicle is 4 wheel drive and 4 wheel ABS. I changed both rear rotors and pads. I compressed the piston before removal. Carefully matched the parts and they are identical. Rear brakes now drag and get hot. All clips were replaced and slide pins cleaned and lubed. Piston slides in smoothly and easily with a c-clamp. Seems slightly better immediately after starting and before first brake use. 1998 chevy s-10 Blazer 4.3L Vortec.
A few questions... Are you sure the thickness of the rotors is about the same as the original? This would be apparent if the caliper was hard to install over the rotors. Was this problem of getting hot the reason for changing the brakes, or is this a new problem? Are you sure the emergency brake shoes was not mis positioned inside the rotor? This could be dragging, and not the regular pads.
Thank you for the reply and questions. Rotor thickness is exactly the same. I seated the piston before I removed the old pads. The caliper went over the new pads with room to spare. I changed the pads just before the problem started. I changed the pads because they were getting a little thin (but probably could have gone another 10 K.) I changed the rotors because I had not in two pad changes and went with new instead of turning them.
The e-brake is shoes in the center of the rotor. It works exactly like before (not too well, needs adjusting next time I'm in there.) and was not moved in any way. Definitely not the problem. It really feels like the brakes are actually being applied and get tighter after the first few second of starting the car. Like as if once the power brakes build a little vacuum, they tighten the rear brakes. Enrico.
OK. Well it sounds like your experienced with auto repair. The brake booster would not be the problem, since it only assists the pressure applied to the master cylinder by the brake pedal. It cannot apply brakes. What you need to do is get the rear of the truck off the ground and wheels off quickly after the brakes start to drag and get hot. Put it in neutral and see how hard it is to turn each rear wheel. See if one side seems hotter than the other.
If they are very stiff, you could possibly have one or both of the caliper hoses collapsed internally and not letting fluid pressure release and release the piston. Loosening the hose on the caliper would relieve the pressure in the caliper and allow the piston to release. This would indicate a bad hose. Have also had an odd problem a few times where the actual pads were the problem.
Some Non factory pads just dont work properly. They get hot and expand or just increase their friction characteristics. Also check the rubber seal on the master cylinder cap to see if it is swollen. This would indicate fluid contamination. If by chance you had it at a quick oil change place recently, they may have add the wrong fluid.