Brakes are one of the most important safety features on your vehicle, so it’s crucial that you keep them well maintained and stay on top of any repairs. We have expert technicians who specialize in brake system repairs and our service center is fully equipped with the best diagnostic and maintenance tools. Below are a list of services and repairs that we provide for brakes. So whether you’re having an issue with your brakes or just want to keep up with the maintenance trust an automotive repair business with properly trained expert automotive repair technicians.
What is the function of the drum brake?
Drum brake systems are typically used to help stop the rear wheels of low performance vehicles and large trucks. Located on the rear axle, they use hydraulic pressure to generate friction and slow the vehicle down. The main components of a drum brake are the wheel cylinder, the brake shoes, the return springs, and the brake drum. The wheel cylinder sits at the top of the drum brake with two pistons inside. When the brakes are applied, the pressurized brake fluid pushes the pistons outward, which in turn force the brake shoes against the outer drum. The result is enough friction to stop a 2 ton vehicle. We recommend that you come in as soon as you notice any signs of malfunctioning brakes. Brake failure is not worth the risk of not bringing it in. Below are a list of common brake problems and their symptoms. If you’re experiencing any of them, bring your car by our repair center.
Common Drum Brake Problems
Drum brakes function by transforming the energy from the engine (in the form of hydraulic pressure) into friction, generating an enormous amount of heat in the process. Consequently, if the outer brake drum is cooled rapidly after heavy use, usually by being exposed to water, warping can occur. Warping can cause a shudder or pulse when the brakes are applied.
Another common problem with drum brakes occurs when the protective coating on the brake shoes wears off. When the brake fluid is released, the brake shoes are pushed outward against the brake drum and the wheels are slowed. Over time, however, the brake shoes become worn down and will need to be replaced.
Drum brakes rely on the hydraulic pressure from compressing brake fluid to generate enough friction to stop a vehicle. If the hydraulic wheel cylinder is leaking, however, fluid will be released into the brake shoes and drum. Consequently, the two forces that are responsible for stopping the car will be compromised—pressure and friction. The wheel cylinder won’t be able to create enough hydraulic pressure to push the brake shoes outward and the brakes shoes will not be able to generate any friction if they’re oily.
Disc brakes are the most common brake systems used in vehicles today. Typically located on the front wheels, they are comprised of brake pads, a brake caliper, and a brake rotor. They function in the same way as brakes on a bike--with brake pads on either side of the wheel that tighten when pressure is applied. The resulting friction slows the wheel down and then brings it to a complete stop. In the same way, disc brake pads straddle the rotor so that when the driver applies the brakes, pressurized fluid is released causing the brake caliper to squeeze the pads together and slow the vehicle down.
Common Disc Brake Problems
There are several things that can go wrong in this kind of brake system. Disc brakes function by transforming the energy from the engine (in the form of hydraulic pressure) into friction, generating an enormous amount of heat in the process. Consequently, if the brakes are quickly cooled when they’re hot—maybe you drove through a puddle—the rotor can become warped. When this happens, you will begin to feel the steering wheel shake when the brakes are applied. To fix this problem, our expert technicians will either replace or resurface your rotor, depending on the degree to which it’s warped.
The disc brake system is constructed around the rotor, which is a metal or ceramic disc that attaches to the axle and rotates with the wheels. When the brake is applied, hydraulic pressure tightens the two brake pads straddling the rotor. This creates enough friction to slow or stop the spinning disc and subsequently the wheel. During this process, an enormous amount of heat is generated. If a hot rotor is cooled too rapidly—such as when a car goes through a puddle—it can become warped. This will cause the brake pedal to shudder or pulse when pressed. To fix this problem, one ofour expert automotive technicians will either replace or resurface your rotor, depending on the degree to which it’s warped. In addition, if you start to hear squealing when the brakes are applied, your rotor might be worn and should be replaced or resurfaced. If you notice any vibration or squealing when braking, bring your car in!
The brake caliper is the component of the disc brake system that conducts hydraulic pressure through the brake pads to the rotor. More specifically, the caliper houses a piston and two brake pads and is connected to a hose containing brake fluid. When the fluid enters, the pressure pushes the piston toward the brake pads, which tighten around the rotor. The resulting friction is what slows the rotor and the wheel. All calipers have a seal protecting them from moisture and dust from the brakes. If this seal is cracking or leaking, it will allow debris and moisture in and around the piston. As a result, the piston will not be able to release completely, and the brake pads will stay in constant contact with the rotor. This will lead to premature wear on all of the elements of the disc brake and will negatively affect braking efficiency. To prevent this from happening, we recommend that you have your calipers carefully inspected each time your brake pads are replaced.
Another common problem that occurs with brake calipers is an air leak. Because the disc brake system relies on hydraulic pressure to create friction, it must be airtight. When air is introduced into the brake fluid it is easier to compress making it harder for the caliper to apply pressure to the brake pads. This problem usually results in a spongy or soft feeling brake pedal. If you experience this, bring you car in. Our expert technicians will perform an air bleed to extract the air from the brake system, which requires opening the caliper’s wheel cylinder and releasing the air within.
Most disc brake systems contain two brake pads that are designed to create friction and straddle the rotor. Each pad has a friction lining that contains semi-metallic compounds and ceramics to create the maximum amount of resistance with the rotor. When the brakes are applied, the caliper uses hydraulic pressure to clench the brake pads together, effectively stopping the rotor and the wheels from spinning. You should have your brakes and your brake pads inspected annually—they are a normal wear item on any car. If your car exhibits squealing brakes, grinding brakes, a pulsating brake pedal, a soft brake pedal, or dragging bring your car in immediately. Brakes are one of the most important safety features on your car, so you want to make sure that they are performing at their best.
Anti-lock Brake Systems are widely used in vehicles today to prevent skidding during emergency brake maneuvers. In a car without ABS, if the brakes are applied and a wheel stops spinning while the vehicle is still in motion, the driver will no longer have control over that wheel. That loss of control could lead to skidding and the inability of the driver to steer properly. A car with ABS, however, will be able to control all four wheels even if they’ve stopped moving. This is because each wheel has a speed sensor attached that relays information to a central ABS computer. If a wheel does stop spinning, the ABS computer will pump hydraulic pressure to that wheel, essentially releasing and then reapplying the brakes. The main issue that arises with Anti-Lock Brakes is faulty sensors. If the speed sensors are not working, the ABS computer won’t know when or to which wheel it needs to pump brake fluid pressure. We recommend that you have your sensors tested when you’re having any other brake maintenance or repairs performed. If your ABS light comes on, bring your car in as soon as possible. Our technicians are ready to put their expertise and years of experience to work on your brakes!
Brake Master Cylinder
Whether your car has a disc or a drum brake system, it contains a brake master cylinder. Located in the driver’s side firewall, the master cylinder is responsible for converting the pressure of the driver’s foot hitting the pedal into hydraulic pressure. It does this by using two pistons to compress brake fluid. A rod connects the brake pedal and these pistons so that when the driver’s foot presses the pedal it’s also pushing the pistons. Subsequently, the brake fluid is pressurized and applied to each wheel. The major problems that arise with the master cylinder stem from leaks. A leaking brake line within the system will make it impossible for the master cylinder to pressurize the brake fluid. When this occurs, the brake pedal will go all the way to the floor when pushed because there is not enough fluid to compress. Master cylinder pistons can also leak if their seals become worn. In either case, you should bring your car in immediately. We have experienced technicians who can handle any problem you’re experiencing with your master cylinder.
Thank you for visiting J & J Auto Service & Transmissions in San Jose, CA. Count on our automotive repair technicians to keep your car, truck, suv, or van on the roads longer and safer.