CDL Air Brakes EXAM ALL Questions and Verified Solutions Latest Update This Year

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CDL Air Brakes EXAM ALL Questions and Verified
Solutions Latest Update This Year
QUESTION: If air pressure is not built up within the correct amount of time, then what will
happen? - ANSWER-air pressure may drop to a low point while driving, requiring an emergency
stop




QUESTION: How often should you drain air tanks? - ANSWER-Daily



QUESTION: A slack adjusters free play needs to be adjusted if it is more than about how many
inches when you pull hard on it? - ANSWER-1 inch




QUESTION: In ideal conditions, a truck or bus with an air brake going at 55 mph would require a
stopping distance of how many feet? - ANSWER-more than 300 feet




QUESTION: If air pressure is not built up within the correct amount of time, then what will
happen to the air pressure? - ANSWER-drop to a low point while driving



requiring an emergency stop




QUESTION: It is accepted that too much heat caused by using your brakes too often can also
cause what? - ANSWER-Brake to fade or fail

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QUESTION: What does the governor control? - ANSWER-when air compressor will pump into air
storage tanks




QUESTION: To make an emergency stop with air brakes, using the stab braking method, you
should do what? - ANSWER-Brake as hard as you can



get off brakes when wheels lock




get back on brakes when wheels start rolling



QUESTION: The driver must be able to see a low air pressure warning which comes on before
pressure in the service air tanks falls below what PSI? - ANSWER-60




Q: Air loss in a straight truck or bus should not be more than how much PSI with the engine off
and the brakes on? - ANSWER-3 PSI in one minute




QUESTION: To make an emergency stop with air brakes, using the stab braking method, you
should - ANSWER-Brake as hard as you can



get off brakes when wheels lock




get back on brakes when wheels start rolling again

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QUESTION: All vehicles with air brakes must have what signal? - ANSWER-Low air pressure
warning signal




QUESTION: It is accepted that too much heat caused by using your brakes too often can also
cause what? - ANSWER-brake to fade or fail



QUESTION: When is it ok to leave your truck unattended without applying the parking brakes
and choking the wheels? - ANSWER-Never




QUESTION: You should know that your brakes are fading when you have to do what? -
ANSWER-push harder on the brake pedal to control your speed on a downgrade




QUESTION: The safety valve discharges automatically at what pressure? - ANSWER-150



QUESTION: What is a dual airbrake system? - ANSWER-2 brake system




one operates front brakes



one operates back brakes




QUESTION: The use of brakes on a long steep downgrade is only a supplement to the braking
effect of the engine - ANSWER-True

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QUESTION: The spring brakes used on the chambers in a straight truck will bring you to a stop
when air pressure drops below what PSI? - ANSWER-60




QUESTION: What do air brakes use to make the brakes work? - ANSWER-Compressed Air



QUESTION: What can legally hold a parking or emergency brake in position for a truck, truck
tractor, or bus? - ANSWER-Spring Pressure




QUESTION: When you put on the brakes by pushing down the brake pedal, what happens? -
ANSWER-Air pressure is applied to the brake pads



QUESTION: Air loss in a straight truck or bus should not be more than what with the engine off
and the brakes on? - ANSWER-3 PSI in one Minute



QUESTION: What does the Emergency Brake System do? - ANSWER-Uses part of the service and
parking brake system to stop the vehicle in the event of a brake system failure



QUESTION: The most common type of foundation brake found on heavy vehicles is what? -
ANSWER-S-cam drum



QUESTION: Modern air brake systems combines what 3 different systems? - ANSWER-Service
Brake