Question 1

A fixed caliper _____.

Accepted Answer

A fixed caliper is indeed bolted to the steering knuckle, has pistons on both sides of the rotor, and does not move when the brakes are applied, making all the provided statements correct.

Question 2

Tapered roller bearings are being discussed. Technician A says the grease seal is installed on the outboard side of the bearing. Technician B says the outer cup, or race, is pressed into the hub. Who is correct?

Accepted Answer

The answer of Tapered roller bearings are being discussed. Technician...

Question 3

Technician A says unidirectional rotors can be installed on either the left side or right side of the car. Technician B says unidirectional rotors run cooler than conventional ventilated rotors. Who is correct?

Accepted Answer

The answer of Technician A says unidirectional rotors can be...

Question 4

After new pads are installed, Technician A breaks in the new pads by making a half dozen or more hard stops from high speed to check whether the brakes will fade when hot. Technician B breaks in the new pads with several gentle to moderate stops, allowing time for the pads and rotors to cool between stops. Who is correct?

Accepted Answer

Technician B's method of breaking in new pads with gentle to moderate stops and allowing cooling time is the correct approach to ensure the pads and rotors are properly bedded without causing damage or premature wear.

Question 5

What component in the brake caliper acts as a retracting mechanism for the piston when hydraulic pressure is released?

Accepted Answer

The square cut O-ring in the brake caliper acts as a retracting mechanism for the piston. When hydraulic pressure is released, the deformation of the O-ring during braking is relieved, which pulls the piston back slightly, ensuring the brake pads do not drag on the rotor.

Question 6

The red brake warning light does NOT turn on when ______.

Accepted Answer

The red brake warning light is designed to alert the driver about issues specifically related to the basic braking system, such as when the parking brake is set, the fluid level in the master cylinder is low, or there is a difference in pressure between brake circuits. It does not turn on for faults in the ABS system; instead, the ABS system has its own separate warning light.

Question 7

Rear disc brakes with auxiliary drum parking brakes automatically adjust when the ______.

Accepted Answer

The answer of Rear disc brakes with auxiliary drum parking...

Question 8

Technician A says a fixed rotor has an integral hub inside which the wheel bearings are mounted. Technician B says a floating rotor is less expensive than a fixed rotor and can be replaced easily and economically. Who is correct?

Accepted Answer

Technician A is correct because a fixed rotor does indeed have an integral hub where the wheel bearings are mounted, making it a single unit. Technician B is also correct because a floating rotor, which is not integrated with the hub, tends to be less expensive and easier to replace than a fixed rotor.

Question 9

Composite rotors are made of cast iron and ______.

Accepted Answer

The answer of Composite rotors are made of cast iron...

Question 10

The customer complains of a high-pitched squeal whenever the wheels are turning, except when the brakes are applied. Technician A says the pads are worn and need replacement. Technician B says the rotors are scored and must be replaced. Who is correct?

Accepted Answer

The high-pitched squeal that stops when the brakes are applied is typically a sign that the brake pads are worn and need replacement. This is because many brake pads have wear indicators that make a squealing noise when the pad material is low, alerting the driver that service is needed. Technician B's diagnosis of scored rotors may not directly cause the squealing noise described, especially since the noise stops when the brakes are applied.

Question 11

Solid rotors are usually found on _____.

Accepted Answer

Solid rotors are typically used on the front brakes of small, compact vehicles due to their lighter weight and lower braking demands, as well as on the rear brakes of vehicles with rear disc brakes where less braking force is required compared to the front.

Question 12

The disc brake piston is made of steel, aluminum, or _____.

Accepted Answer

Phenolic resin is commonly used in the manufacturing of disc brake pistons due to its high heat resistance and durability, making it suitable for the high-temperature environment of braking systems.

Question 13

Electronic brake pad wear warning systems are being discussed. Technician A says the pad wear sensors are wired in parallel. Technician B says the wear sensors are wired in series. Who is correct?

Accepted Answer

The answer of Electronic brake pad wear warning systems are...

Question 14

Which of the following is NOT part of a caliper assembly?

Accepted Answer

The anchor pin is not part of a caliper assembly; it is part of the brake system used to secure the brake caliper or brake shoes in place, but it is not a component within the caliper itself. The piston, dust boot, and square cut seal are all integral parts of a caliper assembly, involved in the mechanism that allows the caliper to apply pressure to the brake pads.

Question 15

Caliper pistons that have threaded adjuster pushrods and internally threaded adjuster nuts are found on ______.

Accepted Answer

Rear wheel actuating calipers often have threaded adjuster pushrods and internally threaded adjuster nuts to accommodate the parking brake mechanism integrated into the caliper.

Question 16

Technician A says the caliper piston seal prevents leakage of brake fluid between the cylinder bore and the piston. Technician B says the caliper piston seal does not contribute to the piston's automatic adjustment feature. Who is correct?

Accepted Answer

Technician A is correct because the caliper piston seal indeed prevents leakage of brake fluid between the cylinder bore and the piston. Technician B is incorrect because the caliper piston seal does contribute to the piston's automatic adjustment feature by creating a slight pull-back effect on the piston as the brakes are released, which helps in adjusting the position of the piston relative to the brake pad wear.

Question 17

A vibration or pulsation in the brake pedal when the brakes are applied is usually caused by ______.

Accepted Answer

Warped rotors can cause uneven contact with the brake pads, leading to a vibration or pulsation felt in the brake pedal when the brakes are applied.

Question 18

Which statement about ceramic rotors is false?

Accepted Answer

Ceramic rotors and the pads used with them actually have a longer lifespan compared to cast iron rotors, not shorter. They are known for their durability and high performance.

Question 19

Brake calipers are being discussed. Technician A says the bleeder screw is located at the bottom of the cylinder bore. Technician B says the fluid inlet hole is located at the top of the cylinder bore. Who is correct?

Accepted Answer

The bleeder screw is typically located at the top of the caliper to allow air to escape during the bleeding process, and the fluid inlet hole is not specifically required to be at the top of the cylinder bore; its position can vary but is generally designed to facilitate efficient fluid flow and operation of the caliper.

Question 20

A hard pedal (abnormally high amount of pedal pressure is required to stop the vehicle)normally indicates a problem with the ______.

Accepted Answer

A hard pedal, requiring an abnormally high amount of pressure to stop the vehicle, typically indicates a problem with the power brake booster. The power brake booster uses vacuum or hydraulic pressure to assist in applying the brakes, reducing the effort needed. If it fails or has issues, much more force on the pedal is required to stop the vehicle.

Quiz 52: Disc Brakes