Exam 51: Drum Brakes

Some vehicles use a(n)____________________ motor to release the parking brake when the engine is running and the transmission is in a forward driving gear.

Riveted linings allow for better heat transfer than bonded linings.

A grinding noise when the brakes are applied could be caused by ______.

Wheel cylinders should be rebuilt or replaced if _____.

Explain how drum brakes create a self-multiplying (self-energizing)brake force.

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

Explain the operation of an integral drum brake parking brake.

Technician A replaces self-adjusters with worn teeth. Technician B swaps the left and right side star wheel adjuster positions so that  the adjuster pawl gets an unworn surface against which to ratchet. Who is correct?

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

Duo-servo drum brake systems are being discussed. Technician A says the primary shoe lining is often thicker than the secondary shoe lining. Technician B says the primary shoe typically has more lining surface area than the secondary shoe. Who is correct?

A customer complains that the car pulls to the left during hard braking. An inspection shows that the front pads and rear shoes are worn. After resurfacing the rotors and drums and replacing the pads and shoes, a road test reveals that the car still pulls to the left during hard braking. Technician A says the wheel alignment should be checked. Technician B says the tires could be the problem and should be swapped left to right to check whether the direction of the pull changes. Who is correct?

Servicing a brake drum with hard spots that are causing chatter and brake pull is being discussed. Technician A says he can grind off the hard spots. Technician B says the drum must be replaced. Who is correct?

What must be done first to remove a brake drum that is ridged and cannot be pulled past the edge of the shoes?

Hydraulic system parts should never have contact with oil or grease.

Small lightweight cars often use duo-servo drum brake designs to reduce brake lockup.

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?

Another term for nonservo-type brakes is ____________________.

Some anchor pins are adjustable.

The brake's ____________________ pin acts as a brake shoe stop and prohibits the brake shoe from its tendency to follow the movement of the rotating drum.

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