DSL-204 Chap 33 Braking Fundamentals and Foundations

Technician A says that the braking system takes vehicle power stored as kinetic energy and converts it back into heat through friction. Technician B says that heat, friction's by-product, is dissipated into the air. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B

A consequence of what phenomenon is that the tires begin to skid, and the driver loses the ability to steer the vehicle?

• Inertia shift

• Wheel lockup

• Brake fade

• Brake torque

While discussing advantages of air brake systems, Technician A says the supply of air is limitless, which allows for minor leaks without the loss of braking. Technician B says that connecting the tractor and trailer braking systems is easier using air lines rather than hydraulic hoses. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B

What are used to prevent a total loss of braking if a failure occurs?

• Parking brakes

• Separate circuits

• Roto-chambers

• Power springs

Wedge brakes use ___________ to multiply braking force.

• Brake pads

• S-shaped cams

• Leverage

• Rollers

Technician A says all brake block friction material is identified by an edge code. Technician B says the friction class is indicated by four letters. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B

__________ produce more brake torque, but often result in uneven brake shoe wear.

• Left-hand camshafts

• Right-hand camshafts

• Cam-same camshafts

• Cam-opposite camshafts

What occurs during chemical fade?

• Brake linings deteriorate due to contamination.

• Brake fluid or other chemicals contaminate the brake linings.

• Steam or gases from vaporized lining material form between the hot lining and drum.

• Glazing appears on the brake linings and drum.

During brake fade, the brakes’ stopping power is __________.

• Controlled

• Increased

• Adjusted

• Reduced

Technician A says it is not necessary that friction material on all axles be replaced at the same time. Technician B says brake torque refers to the force applied to the foundation brakes during braking and is calculated by the vehicle manufacturer using several variables. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and Technician B

• Neither Technician A nor Technician B