CDL Air brakes 1Quiz 1

How do you manually adjust the slack adjuster?

• Turn the adjusting nut right until it cannot move anymore.

• Screw the adjusting nut until the slack adjuster’ end stops moving toward the chamber. Then turn the nut ¼ of a turn in the other direction to pull the brake shoes away from the inside of the brake drum.

• Turn the adjusting nut left until it cannot move any more.

• None of the above

Answer explanation

Screw the adjusting nut until the slack adjuster’ end stops moving toward the chamber. Then turn the nut ¼ of a turn in the other direction to pull the brake shoes away from the inside of the brake drum.

Can you leave your truck without putting on the parking brakes or chocking the wheels first?

• Yes, only if you will only be away from the truck for a few minutes

• Yes, if you are conducting the pre-trip inspection.

• No, never.

Answer explanation

No, never.

How do you check if the air compressor governor is working correctly?

• Look at the air pressure gauge and see if it has normal pressure levels.

• Raise the air pressure until the air compressor is turned off and then lower the air pressure: keep stepping on and off the pedal until the air compressor turns on.

• Keep lowering the pressure until the air compressor turns on.

• None of the above.

Answer explanation

Raise the air pressure until the air compressor is turned off and then lower the air pressure: keep stepping on and off the pedal until the air compressor turns on.

When performing the walk around inspection of the vehicle, you should examine the brake drums to make sure there are no cracks that are longer than ______ width of the friction area?

• One half

• One quarter

• One third

• One eight

Answer explanation

During the walk around inspection, you should check the brake drums for cracks longer than one third of the width of the friction area to ensure safety.

All vehicles with air brakes have_____.

• An alcohol evaporator

• A supply pressure gauge

Answer explanation

All vehicles with air brakes have a supply pressure gauge, which is essential for monitoring the pressure in the air brake system.

What is the proper way to use anti-lock brakes?

• brake normally.

• Brake hard.

• Brake softly.

• Repeat braking.

Answer explanation

To use anti-lock brakes properly, brake normally. This allows the system to work effectively in preventing wheel lock-up during sudden stops.

Before driving a vehicle that is equipped with dual air brakes, it is recommended that a driver wait until the air pressure in both the main and secondary brake systems reach a minimum of ___ psi.

• 25

• 50

• 100

• 125

Answer explanation

Before driving a vehicle with dual air brakes, it is recommended to wait until both main and secondary brake systems reach a minimum of 100 psi.

What should you do to determine the static air leakage rate?

• Keep the engine running and let go of the parking brake.

• Turn off the engine, let go of the parking brake and wait for the system to settle.

• Keep the engine running while charging the system.

Answer explanation

Turn off the engine, let go of the parking brake and wait for the system to settle.

How do you determine if your brakes are fading?

• Your braking distance is short than before

• You need to press the brake pedal harder than usual to slow down.

• The brake feels normal when you apply it.

Answer explanation

You need to press the brake pedal harder than usual to slow down.

When doing the final check, how do you determine if the spring brakes come on when the system air pressure drops below a specific level?

• Park the vehicle, drain off air pressure and wait till the warning lights turn on.

• Park on level ground, chock the wheels, release the parking brake when you have enough air pressure, shut the engine off, then repeatedly press on and off the brake pedal until the warning light comes on.

• Park on level ground, chock the wheels, wait for the air pressure to lower to normal levels, put the truck in first gear and move the truck

Answer explanation

Park on level ground, chock the wheels, release the parking brake when you have enough air pressure, shut the engine off, then repeatedly press on and off the brake pedal until the warning light comes on.