Exam 51: Drum Brakes

A car with a broken timing belt is towed to your shop. The tow truck operator set the parking brake. The vehicle has a automatic vacuum parking brake release. Because the engine can't be started, the brakes won't release. How do you get the car into the shop?

Both non-servo drum brake leading and training shoes are self-energizing as the brakes are applied and the vehicle is moving forward.

On duo-servo drum systems, the forward brake shoe is often called the ____________________ shoe.

Technician A says brake shoe return springs can be separately hooked into a link or a guide. Technician B says the springs may be strung between the shoes. Who is correct?

List five types of wear or distortion to look for when inspecting brake drums.

What is the difference between return springs and holddown springs?

Technician A says on most vehicles, the self-adjuster system is installed on the primary shoe. Technician B says the system will self-adjust when the brakes are applied and the vehicle is backing up. Who is correct?

Technician A removes brake dust from the brake assembly with compressed air. Technician B uses an OSHA-approved brake washer to clean drum brake assemblies. Who is correct?

The function of the wheel cylinder is to ______.

In normal forward braking, the friction developed by the primary lining is greater than the secondary lining.

In a typical drum brake, which component provides a foundation for the brake shoes and associated hardware?

Describe how to test a parking brake.

Regardless of the method of attachment, brake shoes are usually held in a position by spring tension.

The parking brake cables should be adjusted before performing regular wheel brake service.

Duo-servo drum brake systems use an adjusting screw assembly and spring to connect the lower ends of the shoes.

The inability of drums to dissipate as much heat as disc brakes is one of the main reasons discs have replaced drums at the front of all late model cars and light trucks

Riveted linings allow for better heat transfer than bonded linings.

A self-adjuster screw mechanism [star wheel] are non directional and can be positioned on either the left or the right side of the vehicle.

Shoe ____________________ springs and shoe holddown parts maintain the correct shoe position and clearance.

Brake drums can be refinished by either turning or grinding on a ____________________.