What to Do When the Caliper Piston Doesn't Retract?
2 Answers
Caliper piston not retracting may indicate an issue with the brake pads, and it's advisable to visit a 4S shop for repairs. The brake caliper is the component that applies force to the brake disc, with the hydraulic pressure generated by the master cylinder ultimately acting on the piston inside the caliper. In ordinary family cars, the brake caliper piston is located on only one side of the caliper, and from the outside, only the caliper and the brake pads fixed to it are visible.
When I find that the caliper pistons aren't retracting, I usually check them myself. First, remove the wheel and carefully observe the piston position, then try to gently push it back. If it doesn't move, it might be due to rust or dirt buildup inside the piston cylinder. In that case, spray some specialized cleaner and lightly apply lubricating oil. If that still doesn't work, consider whether the piston seals have aged or been damaged—then replacement parts are necessary. The whole process requires patience, but remember safety first—driving with brake issues is dangerous, so ensure the car is parked stably and the jack is securely positioned before starting. Regularly replacing brake fluid also helps prevent corrosion caused by moisture infiltration. DIY repairs can save money, but if you lack experience, it's better to leave it to professional technicians to avoid making things worse.
