Exam 51: Drum Brakes

Servicing a brake drum with hard spots that are causing chatter and brake pull is being discussed. Technician A says grinding off the hard spots is a long-term repair. Technician B says the drum must be replaced. Who is correct?

Identify the two drum brake system designs in common use.

Identify six common brake problems.

Rear wheel brake drum removal is being discussed. Technician A says that on some FWD vehicles, the rear bearings must be disassembled to remove the drum. Technician B says that on some FWD vehicles, the drums are held in place by wheel lugs. Who is correct?

Technician A says self-adjustment occurs on most duo-servo brakes whenever the foot brake is applied while backing up. Technician B says self-adjustment occurs on a non-servo brake whenever the foot brake is applied when driving forward. Who is correct?

Technician A says some drums are made entirely of cast iron. Technician B says some drums are made entirely of aluminum. Who is correct?

Before removing the drum on a nondriven wheel, ______.

To dissipate the heat from braking, the brake drum acts as a heat ____________________.

Parking brake mechanisms provide a hydraulic force to apply the brake shoes and keep the vehicle stationary.

Brake linings should be replaced when linings are ______.

Technician A says the discard dimension of a brake drum is the drum's allowable machining dimension. Technician B says a drum may be machined and used if within 10 percent of the discard dimension. Who is correct?

What tool is used to adjust the brake shoes before the drum is installed?

A floating drum is mounted on hub and wheel bearing assembly.

A drum with a taper or out-of-roundness exceeding 0.006 inch ( .152 mm) is ______.

Another term for nonservo-type brakes is ____________________.

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

List four components of a wheel cylinder.

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?

The brake shoe lining provides ____________________ against the drum to stop the car.

Technician A tests brake drums for out-of-round using a dial indicator. Technician B measures the drum diameter in several places to check for out-of-round. Who is correct?