Montana CDL — Air Brakes Practice Test 9

11.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

12.Your vehicle applies its spring brakes with a modulating control valve on the dash. How does the manual say to park it?

Push the lever to the end of its travel and lock it there with the locking deviceMove the lever halfway so the springs are not overstressedLeave the lever released and rely on wheel chocks alonePump the lever until the low air warning comes on

13.During the emergency brake test on the vehicle inspection test, you are fanning off air in a vehicle whose valves are not the pop-out kind. How does the manual say you will know the parking or emergency brakes have applied?

By listening for air discharging from the air systemBy watching for the ABS lamp to flashBy feeling the brake pedal go to the floorBy waiting until the gauge reads zero

14.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

15.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

16.In the air leakage rate test on the vehicle inspection test, you shut off the engine, release the brakes and press the foot brake all the way down. When does the manual's one-minute count begin?

The moment the engine is shut offAfter the gauge needle settles following the first drop caused by the brake applicationWhen the low air warning comes onAfter the parking brake valve pops out

17.Montana's manual defines the Air Brake Restriction (L Restriction). Which examinations does it say a driver must pass to show he or she is qualified to operate an air brake equipped vehicle?

A written exam, a pre-trip inspection, a basic skills test and a road testThe written test onlyThe road test onlyThe written test and a vision screening

18.A driver makes a habit of manually adjusting his truck's automatic slack adjusters every week. Besides hiding a mechanical problem, what does the manual say this routine is likely to cause?

Higher governor cut-out pressureFaster air pressure buildupA longer push rod stroke limitEarly wear of the adjuster itself

19.The manual's standard for a dual air system is 45 seconds to climb from 85 psi to 100 psi at operating rpm. When does it say a longer time can still be safe?

When the outside temperature is below freezingWhen the vehicle has air tanks larger than the minimum sizeWhen the vehicle is fully loadedWhen the alcohol evaporator is empty

20.You are building air pressure in a dual system before a trip. At what point does the manual say the low air warning light and buzzer should go off?

As soon as either system passes 20 psiWhen both systems reach a manufacturer-set value that is above 55 psiOnly when both systems reach governor cut-outWhen the primary system alone reaches 100 psi