CDL AIR BRAKE PRACTICE SET 2026
TESTED QUESTIONS AND CORRECT
SOLUTIONS
◉ When should you use the parking brakes and air brakes at the same
time?Answer: Never
◉ To correct a drive-wheel braking skid, you shouldAnswer: stop
braking turn quickly and counter steer
◉ During your final air brake check, if the air pressure does not build up
fast enough,Answer: the air may drop during driving
◉ As part of your vehicle inspection test, if your vehicle is equipped
with air brakes and has a trailer, you will inspect the air connections
between the truck or tractor and the trailer. Make sure that the ________
are locked in place and free of damage or air leaks.Answer: Glad hands
◉ On a long or steep downgrade, once you have reached your "safe"
speed, brake until you are travelingAnswer: 5 mph slower
◉ If you must make an emergency stop, brake so thatAnswer: your
vehicle should stay in a straight line
◉ The safety valve is set to automatically reduce pressure atAnswer:
150 PSI
, ◉ In which of the following situations should you NOT apply the
parking brakes?Answer: If the brakes are very hot
◉ When you pull hard on a slack adjuster, if it has more than ________
of free play, the slack adjuster may need adjustment.Answer: 1 inch
◉ How would you check your truck's slack adjusters?Answer: Park on
ground level, turn off the parking brakes, and pull hard on each slack
adjuster. It should'nt move more than 1 inch
◉ 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
toAnswer: 35 mph
◉ To apply the parking brakes under normal conditions,Answer: Let air
out the brake chambers.
◉ To check the slack adjusters on S-cam drum brakes, you should
firstAnswer: Park at ground level, chock the wheels, and release the
parking brakes
◉ When should you manually adjust an automatic slack
adjuster?Answer: only if its not working properly
TESTED QUESTIONS AND CORRECT
SOLUTIONS
◉ When should you use the parking brakes and air brakes at the same
time?Answer: Never
◉ To correct a drive-wheel braking skid, you shouldAnswer: stop
braking turn quickly and counter steer
◉ During your final air brake check, if the air pressure does not build up
fast enough,Answer: the air may drop during driving
◉ As part of your vehicle inspection test, if your vehicle is equipped
with air brakes and has a trailer, you will inspect the air connections
between the truck or tractor and the trailer. Make sure that the ________
are locked in place and free of damage or air leaks.Answer: Glad hands
◉ On a long or steep downgrade, once you have reached your "safe"
speed, brake until you are travelingAnswer: 5 mph slower
◉ If you must make an emergency stop, brake so thatAnswer: your
vehicle should stay in a straight line
◉ The safety valve is set to automatically reduce pressure atAnswer:
150 PSI
, ◉ In which of the following situations should you NOT apply the
parking brakes?Answer: If the brakes are very hot
◉ When you pull hard on a slack adjuster, if it has more than ________
of free play, the slack adjuster may need adjustment.Answer: 1 inch
◉ How would you check your truck's slack adjusters?Answer: Park on
ground level, turn off the parking brakes, and pull hard on each slack
adjuster. It should'nt move more than 1 inch
◉ 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
toAnswer: 35 mph
◉ To apply the parking brakes under normal conditions,Answer: Let air
out the brake chambers.
◉ To check the slack adjusters on S-cam drum brakes, you should
firstAnswer: Park at ground level, chock the wheels, and release the
parking brakes
◉ When should you manually adjust an automatic slack
adjuster?Answer: only if its not working properly
