CDL - SECTION 5 - AIR BRAKES EXAM QUESTIONS

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CDL - SECTION 5 - AIR BRAKES EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -16 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation Question 1: 1. Why should you be in the proper gear before starting down a hill?

Answer:

so you don't have to wear your brakes out slowing down

Question 2: 2. What is a supply pressure gauge used for?

Answer:

To tell you how much pressure is in the air tanks

Question 3: 6. What are the maximum leakage rates?

Answer:

less than 2psi in one minute in single vehicles, less than 3psi in one minute for combination vehicles.then apply 90 psi or more with the brake pedal, if the drop is more than 3psi for singles or 4psi for combo's the air loss rate is too much

Question 4: 5. Front wheel brakes are good under all conditions. True or false?

Answer:

True, make sure the control is in the normal position

Question 5: 3. The use of brakes on a long steep downgrade is only a supplement to the braking effect of the engine. True or false?

Answer:

True, use the 5 mph safe speed rule

Question 6: 1. Why must air tanks be drained?

Answer:

To remove any water or oil

Question 7: 4. How can you test the low pressure warning signal?

Answer:

shut the engine off when you have enough pressure that the low pressure warning signal is not on. turn the electrical power on and step on and off the brake pedal to reduce the air pressure in the tank. the warning signal must come one before the pressure drops to less than 60psi

Question 8: 3. How can you check slack adjusters?

Answer:

Pull hard in each slack adjuster you can reach. if it moves more than about 1 inch where the push rod attaches to it, it probably needs adjustment Question 9: 5. What can you check to make sure the spring brakes come on automatically?

Answer:

Reduce the air pressure in the tank by fanning the brake peddle, the tractor protection valve and parking brake valve should close. this should cause the spring brake to come on Question 10: 4. If you are away from your vehicle only a short time, you don't need to use the parking brake. True or false?

Answer:

False, truck could roll away

Question 11: 5. How often should you drain air tanks?

Answer:

End of each working day

Question 12: 2. What are the slack adjusters?

Answer:

a slack adjuster is a lever arm connected to the brake chamber's push rod at the clevis assembly. it adjusts the brakes to make up for lining wear.

Question 13: 1. What is a dual air brake system?

Answer:

Has two separate air brake systems which use a single set of brake controls.

Question 14: 2. What factors can cause brakes to fade or fail?

Answer:

Too much heat from over use and not using engine braking

Question 15: 4. What are spring brakes?

Answer:

a heavy spring that will engage the brakes if all air is out of the brake system Question 16: 3. All vehicles with air brakes must have a low air pressure warning signal. True or false?

Answer:

True, they must come on before the tank falls below 60 psi