New Mexico CDL — Air Brakes Practice Test 4

1.Four drivers run the Step 7 air leakage tests with the engine off. Whose result is more than the manual allows?

A straight truck, brakes released: 1.5 psi lost in one minuteA tractor-trailer, brakes released: 2.5 psi lost in one minuteA tractor-trailer, foot brake held down: 4.5 psi lost in one minuteA straight truck, foot brake held down: 2.5 psi lost in one minute

2.How many components does New Mexico's manual say make up the air brake check on the vehicle inspection test, and what follows if they are not all performed correctly?

Four components; points are deducted for each one missedTwo components; only the air brake check has to be repeatedThree components; the vehicle inspection test is failed automaticallySeven components; the examiner allows one retry on the spot

3.Section 5 tells you to use a low or lower gear in several situations. Which of these is NOT one of them?

Testing whether the parking brake will holdRolling forward for the five-mph service brake testDrying very wet brakes before parking in freezing weatherResponding to brakes that are starting to fade

4.A driver who studied another state's manual tests the low pressure warning on a late-model New Mexico truck. Pumping the brake pedal with the engine off, he sees the warning first come on at 57 psi and calls it a pass. How does that compare with Section 5 of New Mexico's manual?

It passes; the signal only has to come on somewhere before pressure reaches 55 psiIt falls short; the signal must come on before pressure drops below 60 psiIt passes; any signal that comes on above 45 psi meets the manual's standardIt falls short; the signal must already be on by the time pressure reaches 85 psi

5.A bus has dual parking control valves. At the end of a run, which of the two does the manual assign to setting the spring brakes when you park?

The valve that is spring loaded in the "out" positionEither one; the two valves do the same jobThe push-pull valveNeither; the brake pedal sets the spring brakes on a bus

6.On New Mexico's CDL Licensing Information sheet, where do air brakes show up?

In the endorsement chart, as endorsement A with a written and a skills testIn the endorsement chart, as part of the combined X endorsementIn the restriction list, as L and Z; there is no air brake endorsementIn the class chart, as a requirement that applies to Class A only

7.Section 5 lists the checks that make up the Step 7 final air brake check. Which one does it list first?

The rate of air pressure buildup at operating rpmThe parking brakeThe low pressure warning signalThe governor's cut-in and cut-out pressures

8.Which of these is NOT part of the manual's procedure for a normal stop in an air-braked vehicle?

Pushing the brake pedal down and controlling the pressure for a smooth stopPulling the parking brake knob as the vehicle slows, to help it stopWith a manual transmission, leaving the clutch alone until engine rpm is near idleChoosing a starting gear once you have stopped

9.Your truck's air compressor is gear-driven, so there is no compressor belt to show the examiner on the vehicle inspection test. What does Section 11 require instead?

Nothing; a component that has no belt is left out of the engine compartment inspection altogetherTell the examiner it is not belt driven, then check that it works, is undamaged, is not leaking and is secureTake off the gear cover so that the examiner can see the compressor drive and judge its conditionRun the engine at a fast idle and time how quickly the air pressure builds to governor cutout

10.Your brakes are out of adjustment. According to the manual's passage on spring brakes, which of your brakes are affected?

Only the regular service brakesOnly the emergency/parking brakesBoth the regular brakes and the emergency/parking brakesNeither of them, provided the tank pressure is still in the normal range