Alabama CDL — Air Brakes Practice Test 6

1.Your brakes have gotten soaked. How does the manual suggest you dry them out?

Roll along in a low gear and apply light brake pressure to warm themPark the truck and wait for the water to evaporate on its ownHold the parking brakes on hard for several minutesPump the pedal rapidly while the vehicle sits still

2.How is the parking brake checked as part of the final air brake test?

Release it on a downgrade and count how far the vehicle rollsSet it with the vehicle stopped and tug against it gently in a low gearApply it at highway speed and time how long the stop takesWatch the application gauge for one minute with the key off

3.Why is it a bad habit to press and release the brake pedal unnecessarily?

It overheats the alcohol evaporatorIt can drain air faster than the compressor can rebuild itIt permanently locks the spring brakes onIt causes the governor to raise the cut-out pressure

4.In the service brake check you creep ahead at roughly five mph and press the pedal firmly. What are you looking for?

A drop in the engine oil pressure readingAir escaping from the alcohol evaporatorThe governor cutting the compressor out earlyThe truck tugging to one side, an odd feel, or a late stop

5.At roughly what tank pressure does the governor stop the compressor from pumping more air (the cut-out point)?

About 55 psiAbout 80 psiAbout 150 psiAbout 125 psi

6.For a vehicle with air brakes, total stopping distance is made up of which four parts?

Perception, reaction, cornering, and coasting distanceFollowing, merging, braking, and reaction distancePerception, reaction, brake lag, and braking distanceIdle, cut-in, cut-out, and braking distance

7.In which situation does the manual allow a driver to push the brake pedal all the way down for an emergency stop?

Any time the road surface is wet or covered with iceWhenever the vehicle happens to be running emptyWhen the truck or combination has antilock braking working on all of its axlesOnly when the trailer by itself carries an antilock system

8.What is the most common problem discovered during roadside inspections of air brake vehicles?

Overfilled alcohol evaporatorsBrakes that are out of adjustmentMissing supply pressure gaugesExcess pressure in the storage tanks

9.What inspection method should be used to check a vehicle equipped with air brakes?

A quick glance at the dash gauges onlyA brake test performed only at highway speedAn inspection limited to the trailer connectionsThe basic seven-step inspection procedure

10.Why is it important to drain the air tanks completely?

To let the compressor cool down between stopsTo lower the pressure so the governor can resetTo add fresh alcohol to the braking systemTo remove water and oil that could cause brake failure