If your truck's air compressor has its own oil supply, when should you first check the oil level?

a) During your first en route inspection

b) Immediately after stopping

c) Before driving

Answer: c) Before driving

You are on a steep downgrade and have reached your "safe" speed of 40 MPH. You would apply the service brakes until your speed drops to ___ MPH.

a) 25

b) 30

c) 35

Answer: c) 35

Truck and bus parking or emergency brakes must be held on by:

a) Air pressure

b) A modulating control valve

c) Mechanical force

Answer: c) Mechanical force

What is emergency controlled braking?

a) You apply the brakes as hard as you can without locking the wheels

b) You brake as hard as you can, release the brakes when the wheels lock, and reapply the brakes when the wheels start rolling

c) Apply the hand valve for one second, then push the brake pedal hard

Answer: a) You apply the brakes as hard as you can without locking the wheels

The air brake lag distance at 55 MPH on dry pavement adds about ___ feet to your stopping distance.

a) 12

b) 32

c) 52

Answer: b) 32

During normal driving, spring brakes are usually held back by:

a) Bolts

b) Spring pressure

c) Air pressure

Answer: c) Air pressure

The safety valve is usually set to reduce air pressure at ___ psi.

a) 50

b) 100

c) 150

Answer: c) 150

Your truck has a properly functioning dual air brake system and minimum size air tanks. The air pressure should build from 85 to 100 psi within:

a) 30 seconds

b) 45 seconds

c) 60 seconds

Answer: b) 45 seconds

The use of air brakes on a downgrade is only a supplement to the:

a) Use of the spring brakes

b) Use of the front brake limiting valve

c) Braking effect of the engine

Answer: c) Braking effect of the engine

When you apply the brakes, the brake shoes/linings are pressed against the:

a) Brake drum or disc

b) Slack adjuster

c) S-cam

Answer: a) Brake drum or disc

What is emergency stab braking?

a) Press hard on the brake pedal and apply full hand valve until you stop

b) Use light steady pressure on the brake pedal

c) Brake hard, release the brakes when the wheels lock, and reapply the brakes when the wheels start rolling

Answer: c) Brake hard, release the brakes when the wheels lock, and reapply the brakes when the wheels start rolling

The application pressure gauge shows how much air pressure you:

a) Have in the air tanks

b) Have in the modulating control valve

c) Are applying to the brakes

Answer: c) Are applying to the brakes

The important thing to do when a low air pressure warning comes on is:

a) Upshift and drive to a safe place

b) Downshift and drive to a safe place

c) Stop and safely park as soon as possible

Answer: b) Stop and safely park as soon as possible

If your vehicle has an alcohol evaporator, it is there to:

a) Rid the wet tank of alcohol that condenses and sits at the bottom

b) Eliminate the need for daily tank draining

c) Reduce the risk of ice in air brake valves in cold weather

Answer: c) Reduce the risk of ice in air brake valves in cold weather

A truck with air brakes going 55 MPH would require a stopping distance of:

a) Less than 100 feet

b) 100-300 feet

c) More than 300 feet

Answer: c) More than 300 feet

Total stopping distance for vehicles with air brakes is longer than that for vehicles with hydraulic brakes due to ___ distance.

a) Brake lag

b) Reaction

c) Effective braking

Answer: a) Brake lag

Excessive use of the service breaks results in overheating, which can lead to:

a) Improper adjustment of the S-cam

b) Increased contact between the brake drums and brake linings

c) Expansion of the brake drums

Answer: c) Expansion of the brake drums