What Happens To Your Calipers When You Ignore Worn Brake Pads?
Modern disc braking systems consist of numerous components and sensors, but there are still three critical components in nearly every car's wheel wells: brake pads, brake discs (or rotors), and calipers. These three components utilize your hydraulic braking fluid to bring your car to a comfortable and controlled stop, and a problem with any of them may impact braking performance.
How Your Brakes Work
The easiest way to imagine your car's disc braking system is to think of a clamp. The rotors spin with your wheels when you aren't pressing on the brake pedal, and hardware on the caliper or bracket maintains a small clearance between the rotors and pads. All disc braking systems use two brake pads — one outboard and one inboard.
The brake pads act as a clamp when you step on your brakes. Both pads push in against the rotor, generating friction that ultimately converts your car's motion into heat energy. The clamping force comes from the caliper, a relatively straightforward device with a hydraulically-actuated piston. Pushing on your brake pedal extends the piston, pushing your pads into contact with the rotor.
Why Brake Service Matters for Your Calipers
Your calipers should normally last for the lifetime of your car, but they require occasional care and can be sensitive to other issues with your brakes. For example, problems with your hydraulic fluid hoses can cause your calipers to seize and potentially force you to replace them. However, the greatest danger to your calipers comes from ignoring routine service jobs.
Since your calipers utilize brake fluid, they must remain sealed to prevent leaks. Additionally, damage to your caliper's seals can allow dirt and moisture to enter them, potentially causing the piston to rust and bind. Under normal circumstances, the thickness of your brake pads helps protect your calipers and prevent the piston from overextending.
Unfortunately, allowing your brake pads to wear down too much (or even wear down to their backing plates) can cause the caliper pistons to overextend. On older cars with worn seals, this may result in the seal cracking or breaking. In a worst-case scenario, the remains of the pad can even fall out, allowing the piston to contact the rotor directly.
What You Can Do to Extend the Life of Your Calipers
The best way to ensure your calipers last for many years is to schedule routine brake service jobs for your vehicle. Changing your brake pads before they become too worn will keep your caliper pistons from overextending, reducing the risk of damage to the seals. Brake technicians will also lubricate the slide pins and keep the calipers clean, ensuring they continue to function correctly.
Get in touch with a brake service before any other issues arise.