Montana CDL — Air Brakes Practice Test 3

1.During the final air brake check, the compressor does not cut in and cut out the way the manual describes. What danger does the manual see in a governor that is not working properly?

The ABS lamp will stay litAir pressure could fall short of what safe driving needsThe spring brakes will never releaseThe brake drums will overheat while parked

2.It is January and your truck has an alcohol evaporator and manually drained air tanks. A coworker says the evaporator means you can skip draining the tanks. What does the manual say?

He is right; alcohol dissolves the water and oil in the tanksHe is wrong; the tanks still need draining every day to remove water and oilHe is right, but only while the temperature stays below freezingHe is wrong; with an evaporator the tanks must be drained after every stop

3.One half of your dual air brake system has dropped very low on pressure while the other half is normal. What does the manual say this means for you?

Nothing changes, because the good half runs every brakeThe spring brakes release and cannot be reappliedThe brakes at one end of the vehicle, front or rear, will not work fully, so stopping takes longerThe trailer brakes lock at once

4.Your pre-trip check shows a brake with an automatic slack adjuster is out of adjustment. What does the manual recommend?

Get the vehicle into a repair shop as soon as you canKeep driving; the adjuster will correct itself within a few stopsBack the adjuster off by hand and recheck it at the end of the weekSwitch the front brake control to "slippery" until the next service

5.On a long grade your application pressure gauge shows you are using more and more pressure just to keep your speed steady. What does the manual tell you to do?

Slow down and shift to a lower gearSpeed up so more air flows over the drumsSwitch the front brake control to "slippery"Pull the parking brake knob to rest the service brakes

6.According to the manual, why can't air pressure alone be trusted to hold the emergency and parking brakes on?

Because the air can leak away over timeBecause air reacts more slowly than mechanical partsBecause air pressure would overheat the drums while parkedBecause air-held brakes never need to be adjusted

7.You are doing the emergency brake test on a tractor pulling an air-operated trailer. According to the manual's inspection section, when should the trailer's parking brake valve and the tractor protection valve pop out compared with the tractor's own valve?

Only after the tractor's valve has popped outNever; trailer valves do not pop outOnly once the gauge reads zeroAt the same time as the tractor's valve, or before it

8.Step 7 of the seven-step inspection in Section 2 includes a hydraulic brake check. What does the Air Brakes section tell drivers of air-braked vehicles to do at that step?

Do the hydraulic check first, then the air brake checksSkip Step 7 entirelyDo the final air brake checks in place of the hydraulic brake checkDo only the parking brake test

9.An applicant takes the CDL skills test in a truck with air over hydraulic brakes. Under the manual's restriction list, what must the state place on the license?

An L restriction: no CMV with any type of air brakesAn E restriction: no manual transmissionA Z restriction: no CMV whose braking system works fully on airNo restriction, because air over hydraulic counts as full air brakes

10.In stab braking, you release the brakes when the wheels lock. What does the manual say happens if you put the brakes back on before the wheels are rolling again?

The vehicle will not straighten outThe spring brakes will applyThe ABS lamp will come onThe stop will be shorter