Virtually all cars produced today contain disc brakes. These hydraulically powered systems stop your car through the action of pincher-like calipers, which close around the rotors, or discs, attached to each of your wheels. As the calipers grip the rotor, the brake pads create friction, which causes the wheel to quickly lose momentum.
Brake calipers experience a lot of mechanical stress over their lifetime. In addition, their relatively exposed position makes them susceptible to wear and tear caused by deicing salts and roadway debris. Eventually, even a well-maintained caliper will fail, necessitating replacement. This article examines three key signs of a failing brake caliper.
1. Leaking Brake Fluid
The hydraulic systems that power brakes are stocked with a durable type of oil known as brake or hydraulic fluid. When you depress your brake pedal, a mechanical signal travels to the master cylinder, which releases the valves necessary to push fluid through a series of hoses to your brake calipers.
Each of the four brake calipers on your car contains its own dedicated piston. Pressurized brake fluid causes the piston to move, in turn triggering the two halves of the caliper to come together around the rotor. In order for a caliper to work smoothly every time, the fluid system must remain tightly sealed.
Unfortunately, as time goes on, a caliper may develop fluid leaks that prevent it from working correctly. Such leaks commonly form as the result of degradation to the rubber seal and/or boot used to prevent fluid from escaping from the piston's cylinder. Once these components become damaged, fluid can press its way right out of the brake line.
As a result, your calipers will struggle to generate the necessary amount of force to stop your vehicle. You may notice that your braking power seems reduced or unusually slow. In addition, you may find tell-tale puddles of brake fluid around your car's wheels. To eliminate this problem, a trained mechanic must replace any affected calipers.
2. Noisy Brakes
Car owners should always take unusual sounds very seriously, as they often indicate serious problems at play. If you notice strange sounds that occur when you engage your brakes, the problem may lie with your calipers. In some cases, the bolts used to attach the calipers may have worked loose, leading to thudding or rattling sounds when you brake.
The problem may also have to do with contaminants that have found their way into the brake lines. Specifically, debris lodged between the piston and the brake pad tends to produce unusual noises.
Not all strange brake sounds indicate a caliper problem. Wheel bearings, brake pads, and rotors can also cause noises if they fall into disrepair. Contact a professional mechanic as soon as possible to help determine the specific issue.
3. Excessive Corrosion
As noted above, brake calipers remain largely exposed to the elements, making rust and corrosion an everpresent threat. Fortunately, corrosion shouldn't prevent your calipers from working correctly if you drive your car on a regular basis. In that case, the friction between moving parts effectively scours away much of the surface corrosion.
Yet when a car sits for long periods of time without running, corrosion can build up to the point that it causes your caliper to seize. As you can probably guess, a seized caliper cannot move properly. In some cases, the caliper may not move at all, while in other cases the caliper may only enjoy a limited range of motion.
A seized caliper often fails to release the rotor entirely even when you are not actively braking. This phenomenon, known as brake drag, may cause your car to veer persistently in one direction or the other. Over time, brake drag also causes overheating and excessive wear to your brake pads.
For more information about how to keep your calipers in good working shape, please contact the brake experts at Ceja Quality Tire & Wheel.