Technician A says that drum servo brakes are self-energizing.Technician B says that servo brakes both primary and secondary shoes play a role in braking the drum whether the vehicle is moving forward or in reverse.Who is correct?

Question

Quizplus · Accepted Answer

Technician A is correct because drum servo brakes are indeed self-energizing, meaning the friction created by the brake shoe contacting the drum helps pull the shoe into the drum, increasing the braking force without additional effort from the driver. Technician B is also correct because in a servo brake system, both the primary and secondary shoes are designed to be self-energizing in one direction (usually forward), and the design allows for effective braking in both directions, although one shoe is more effective in the forward direction and the other in reverse.

Technician a Says That Drum Servo Brakes Are Self-Energizing