What is a slack adjuster?

What is a slack adjuster?a) It is the space between the rear wheelsb) It is an adjusting nut on the backside of the brake drum, used for adjusting the...

With air brake-equipped vehicles, the parking brakes should be used

With air brake-equipped vehicles, the parking brakes should be useda) As little as possibleb) Whenever you leave the vehicle unattendedc) Only during...

What is the danger of non-functioning low pressure warning signal?

What is the danger of non-functioning low pressure warning signal?a) You could lose air pressure, but you would know about it anywayb) This could cause...

When you pull hard on a slack adjuster, if its free play is more than ___, the slack adjuster will need to be adjusted.

When you pull hard on a slack adjuster, if its free play is more than ___, the slack adjuster will need to be adjusted.a) ½ inchb) ¼ inchc) 1 inchAnswer: c)...

When you apply the brakes by pushing down on the brake pedal,

When you apply the brakes by pushing down on the brake pedal,a) Air pressure is reduced to the brake padsb) Compressed air is let out of the systemc)...

To make an emergency stop with air brakes, using the stab braking method, you should

To make an emergency stop with air brakes, using the stab braking method, you shoulda) Brake hard until the wheels lock and then get off the brakes for...

Oil and water usually collect in compressed air tanks. If you do not have an automatic tank drain, when should you drain the air tanks?

Oil and water usually collect in compressed air tanks. If you do not have an automatic tank drain, when should you drain the air tanks?a) After every...

The safety valve is set to automatically reduce pressure at __ psi.

The safety valve is set to automatically reduce pressure at __ psi.a) 150b) 50c) 100Answer: a) ...

Which conditions are ideal for front wheel brakes?

Which conditions are ideal for front wheel brakes?a) Noneb) All weather conditionsc) Only wet or icy conditionsd) Only good weatherAnswer: b) All...

At what measurement is the safety valve USUALLY set to open?

At what measurement is the safety valve USUALLY set to open?a) 250 psib) 150 psic) 200 psid) 100 psiAnswer: b) 150 ...

How do brakes work on a long, steep downgrade?

How do brakes work on a long, steep downgrade?a) They work as the main braking mechanismb) They work as the main braking mechanism, with the engine braking...

The maximum leakage rates per minute after the initial pressure drop are

The maximum leakage rates per minute after the initial pressure drop area) 5 psi for single vehicles and 10 psi for combination vehiclesb) 3 psi for single...

The purpose of a supply pressure gauge is

The purpose of a supply pressure gauge isa) To tell you how hot the air in the tank isb) To tell you how much air is in the tankc) To warn you if there...

Which of the following can cause brakes to fail or fade?

Which of the following can cause brakes to fail or fade?a) Brakes being out of adjustmentb) Not relying on engine braking enoughc) Excessive use of the...

Which of the following will be true about your brake function if your ABS fails?

Which of the following will be true about your brake function if your ABS fails?a) You will have to brake function, and the truck will be out of controlb)...

Spring brakes are

Spring brakes area) Brakes that come on automatically on a truck on tractor when the psi drops too lowb) Make up of powerful springs that are help back...

Which vehicles must have low air pressure warning signals?

Which vehicles must have low air pressure warning signals?a) Only those built after 2005b) Only those built after 2010c) Noned) All vehicles with air...

Why must you study air brakes in the state of California?

Why must you study air brakes in the state of California?a) Otherwise, you will have to get a CDL with restrictionsb) Otherwise, you cannot get a CDL...

When should you use the parking brake?

When should you use the parking brake?a) Every time you leave your vehicle, with rare exceptionsb) Every time you leave your vehicle for any period of...

Which of the following should you do before leaving your vehicle unattended?

Which of the following should you do before leaving your vehicle unattended?a) Put on the parking brakesb) Chock the wheelsc) Remove the keysd) Do all...

An anti-lock braking system (ABS)

An anti-lock braking system (ABS)a) Increases your normal braking capabilityb) Decreases your normal braking capabilityc) Shortens your stopping distanced)...

Which of the following is true about a dual air brake system?

Which of the following is true about a dual air brake system?a) One system is called the "primary" system and the other one is called the "secondary"...

How can you tell if your vehicle is equipped with an anti-lock braking system (ABS)?

How can you tell if your vehicle is equipped with an anti-lock braking system (ABS)?a) The vehicle was manufactured after 2000b) ABS is still optionalc)...

When should you drain your air tanks?

When should you drain your air tanks?a) At the end of a tripb) At the end of each working dayc) At the end of the fiscal quarterd) At the end of the monthAnswer: b)...

Slack adjusters are

Slack adjusters area) Part of your air brake system used to adjust the brakesb) Between the push rod and S-cam on drum brakesc) Between the power screw...

Which of the following is NOT part of the drum brake?

Which of the following is NOT part of the drum brake?a) Brake drumb) Safety valvec) Axled) Slack adjusterAnswer: b) Safety va...

How would you check your truck's slack adjusters?

How would you check your truck's slack adjusters?a) Use gloves and pull hard on each slack adjuster you can reachb) Accelerate and then brake hardc) Press...

Which of the following is NOT part of the braking process when driving a tractor-trailer combination vehicle with an anti-lock braking system (ABS)?

Which of the following is NOT part of the braking process when driving a tractor-trailer combination vehicle with an anti-lock braking system (ABS)?a)...

Which of the following is NOT part of the air brake system?

Which of the following is NOT part of the air brake system?a) Parking brake systemb) Service brake systemc) Radio signal systemd) Emergency brake systemAnswer: c)...

If you are driving down a steep downgrade and you have reaches your "safe" speed of 40 mph, you would apply the service brakes until your speed drops to ___ mph.

If you are driving down a steep downgrade and you have reaches your "safe" speed of 40 mph, you would apply the service brakes until your speed drops...

Parking or emergency brakes of trucks and buses can be legally help on by ___ pressure.

Parking or emergency brakes of trucks and buses can be legally help on by ___ pressure.a) Springb) Fluidc) AirAnswer: c) ...

The tractor protection valve

The tractor protection valvea) Closes if you apply the parking brakesb) Provides the air supply for the brake systemc) Will close itself automatically...

What is the best way to test your vehicle's low air pressure warning signal?

What is the best way to test your vehicle's low air pressure warning signal?a) Pump the brakes while your vehicle is fully onb) With the engine off, step...

Which of the statements is the proper way to signal for a lane change?

Which of the statements is the proper way to signal for a lane change?a) Signal just as you begin to change lanes, and drift over slowlyb) Signal early,...

What is the first thing you should do if your brakes fail while driving downhill?

What is the first thing you should do if your brakes fail while driving downhill?a) Call or radio for helpb) Try to use ur parking brake to stopc) Get...

Which of these is true about shipping hazardous materials?

Which of these is true about shipping hazardous materials?a) A four-inch, circular, red hazardous materials label must be on the containerb) Gas cylinders...

If you must drive into the oncoming lane to turn, you should:

If you must drive into the oncoming lane to turn, you should:a) Allow enough space to get completely across the intersectionb) Back up to allow oncoming...

The Commercial Driver Handbook suggests several things to do when you pass a vehicle. Which of these is NOT one of them?

The Commercial Driver Handbook suggests several things to do when you pass a vehicle. Which of these is NOT one of them?a) Lightly tap your horn, if neededb)...

You can see this sign on a vehicle ahead of you. What does this sign mean?

You can see this sign on a vehicle ahead of you. What does this sign mean?a) Slow moving vehicleb) Hazardous materials on boardc) Student driverAnswer: a)...

Optional safety equipment may include emergency phone numbers, tire chains, and:

Optional safety equipment may include emergency phone numbers, tire chains, and:a) Tire changing equipmentb) Red reflective trianglesc) Charged fire extinguisherAnswer: a)...

You are checking your ties during a pre-trip inspection. Which of these statements is true?

You are checking your ties during a pre-trip inspection. Which of these statements is true?a) Tires of mismatched sizes should not be used on the same...

You should try to park your vehicle so:

You should try to park your vehicle so:a) You can pull forward when you leaveb) There is at least one curb next to your vehiclec) Your vehicle is protected...

Whenever you double your speed, it will take about ___ times as much distance to stop.

Whenever you double your speed, it will take about ___ times as much distance to stop.a) Twob) Threec) FourAnswer: c) F...

The braking effect of the engine is greatest when the engine is ___ the governed RPMs and the transmission is in the ___ gears.

The braking effect of the engine is greatest when the engine is ___ the governed RPMs and the transmission is in the ___ gears.a) Above, lowerb) Below,...

You are checking your brakes and suspension system during a pre-trip inspection. Which of these statements is true?

You are checking your brakes and suspension system during a pre-trip inspection. Which of these statements is true?a) Just one missing leaf spring is...

Which of these is NOT a proper use of vehicle lights?

Which of these is NOT a proper use of vehicle lights?a) Turning on your headlights during the day when visibility is reducedb) Flashing your break lights...

Which of the following is NOT a type of retarder?

Which of the following is NOT a type of retarder?a) Electricb) Hydraulicc) RoboticAnswer: c) Robo...

Which of the following may be a sign of tire failure?

Which of the following may be a sign of tire failure?a) A loud hissing noiseb) Gentle thumpingc) Wheels fishtailingAnswer: c) Wheels fishtail...

The best drivers are those who watch and prepare for hazards. This is called being:

The best drivers are those who watch and prepare for hazards. This is called being:a) Offensiveb) Defensivec) ObjectiveAnswer: b) Defens...

You are driving in heavy traffic at 35 MPH. The speed limit is 55 MPH. The safest speed for your vehicle is:

You are driving in heavy traffic at 35 MPH. The speed limit is 55 MPH. The safest speed for your vehicle is:a) 25 MPHb) 45 MPHc) 35 MPHAnswer: c)...

Which of these statements is true about brakes?

Which of these statements is true about brakes?a) Brakes absorb more heat to stop heavier or faster moving vehiclesb) Brake drums cool very quickly when...

You are exiting a highway using an offramp that curves downhill and your are driving a heavy vehicle. You should:

You are exiting a highway using an offramp that curves downhill and your are driving a heavy vehicle. You should:a) Do nothing because the posted speed...

When hydraulic brakes fail, the system won't build up pressure and the brake pedal will feel spongy or go to the floor. What action should you take?

When hydraulic brakes fail, the system won't build up pressure and the brake pedal will feel spongy or go to the floor. What action should you take?a)...

Which of these statements is true about rear drive wheel braking skids?

Which of these statements is true about rear drive wheel braking skids?a) Locked wheels usually have more traction that rolling wheelsb) Front wheels...

Which of these statements is true about cargo types?

Which of these statements is true about cargo types?a) Unstable loads (i.e. hanging meat, livestock) require extra caution on curvesb) Oversize loads...

The total weight of a powered unit, the trailer, and the cargo is called:

The total weight of a powered unit, the trailer, and the cargo is called:a) Gross vehicle weightb) Gross combination weightc) Gross axle weightAnswer: b)...

Which of these is NOT checked in a pre-trip inspection?

Which of these is NOT checked in a pre-trip inspection?a) Whether all vehicle lights are working and are cleanb) Cargo securementc) Amount of fuel in...

You are driving a 40' vehicle at 35 MPH. The road is dry and the visibility is good. What is the least amount of space that you should keep in front of your vehicle to be safe?

You are driving a 40' vehicle at 35 MPH. The road is dry and the visibility is good. What is the least amount of space that you should keep in front of...

Which of these is true about your overhead clearance?

Which of these is true about your overhead clearance?a) Paving the road does not affect the clearance height under bridges or overpassesb) The weight...

Which of the following is the correct term for a long commercial vehicle's tendency to swing wide on turns?

Which of the following is the correct term for a long commercial vehicle's tendency to swing wide on turns?a) Sidetrackingb) Offtrackingc) FishtailingAnswer: b)...

If you are stopped on a one-way or divided highway, you should place reflective triangles at:

If you are stopped on a one-way or divided highway, you should place reflective triangles at:a) 10 feet, 100 feet, 200 feet toward approaching trafficb)...

Water can be safely used on which of these fires?

Water can be safely used on which of these fires?a) Electricalb) Gasolinec) Neither of the aboveAnswer: c) Neither of the ab...

A pre-trip inspection should be completed:

A pre-trip inspection should be completed:a) At least once a weekb) If any problems occurred the last time the vehicle was operatedc) Before operating...

What are three things that add up to the total stopping distance for your truck or bus?

What are three things that add up to the total stopping distance for your truck or bus?a) Attention distance, Reaction distance, slowing distanceb) Observation...

What should you do when you are driving at night?

What should you do when you are driving at night?a) Make sure you are driving slow enough so you can stop within the range of your headlights in an emergencyb)...

CDL medical certificates must be renewed every:

CDL medical certificates must be renewed every:a) Yearb) Two Yearsc) Four yearsAnswer: b) Two Ye...

The maximum distance you can stop away from a railroad crossing is:

The maximum distance you can stop away from a railroad crossing is:a) 20 feetb) 50 feetc) 70 feetAnswer: b) 50 f...

Which of the following types of cargo can never be carried on a bus?

Which of the following types of cargo can never be carried on a bus?a) Small arms ammunition labeled ORM-Db) Irritating materials or tear gasc) Hospital...

The total maximum weight of hazardous materials that buses are allowed to carry is ___ pounds.

The total maximum weight of hazardous materials that buses are allowed to carry is ___ pounds.a) 100b) 250c) 500Answer: c) ...

When driving a bus, the emergency roof hatches:

When driving a bus, the emergency roof hatches:a) Must always be completely closed and locked while the bus is movingb) May be locked in a partially open...

Buses may not carry move than ___ pounds of any one class of allowed hazardous materials.

Buses may not carry move than ___ pounds of any one class of allowed hazardous materials.a) 100b) 250c) 500Answer: a) ...

When driving a bus, you should look ___ seconds ahead of you.

When driving a bus, you should look ___ seconds ahead of you.a) 3-6b) 7-10c) 12-15Answer: c) 12...

You are driving a 40' bus at 30 MPH. The road is dry and visibility is good. You should keep a safety space in front of your bus that is at least ___ seconds.

You are driving a 40' bus at 30 MPH. The road is dry and visibility is good. You should keep a safety space in front of your bus that is at least ___...

A standee line on the bus:

A standee line on the bus:a) Is required when carrying less than 15 ridersb) Indicates where you should stand when talking to passengersc) Is the line...

Drivers of charter buses should NOT allow riders on the bus until:

Drivers of charter buses should NOT allow riders on the bus until:a) All baggage has been loadedb) All scheduled passengers have arrived at the stationc)...

Buses may have recapped or regrooved tires:

Buses may have recapped or regrooved tires:a) Only as the outside on a set of dualsb) On any or all of the wheelsc) Anywhere except the front wheelsAnswer: c)...

You should check your mirrors:

You should check your mirrors:a) Immediately after starting a lane changeb) As you prepare to stopc) Regularly as part of your scan for potential hazardsAnswer: c)...

If your bus has an emergency exit door, it must:

If your bus has an emergency exit door, it must:a) Be closed when operating the busb) Always have a red door light and it must be lightedc) Sound an alarm...

Which of these actions will result in the best control on a curve?

Which of these actions will result in the best control on a curve?a) Slow to a safe speed before entering a curve, then accelerate slightly through itb)...

Baggage or freight carried on a bus must be secured:

Baggage or freight carried on a bus must be secured:a) In a compartment away from passengersb) In front of the standee linec) So any door or window can...

Your bus is disabled. The bus, with riders on board, may be towed or pushed to a safe spot to discharge the passengers only if:

Your bus is disabled. The bus, with riders on board, may be towed or pushed to a safe spot to discharge the passengers only if:a) The distance is less...

When waiting to merge into traffic, you should:

When waiting to merge into traffic, you should:a) Always wait for a large enough gap before mergingb) Pull out slowly and gradually reach the speed of...

You may sometimes transport small arms ammunition or emergency hospital supplies on a bus. The total weight of these hazardous materials must not exceed ___ pounds.

You may sometimes transport small arms ammunition or emergency hospital supplies on a bus. The total weight of these hazardous materials must not exceed...

You are driving at night and you must dim your headlights from high to low. What should you should you do with your speed?

You are driving at night and you must dim your headlights from high to low. What should you should you do with your speed?a) Drop 5 MPH until your eyes...

If a rider wants to get on the bus with a car battery or a can of gasoline, you should:

If a rider wants to get on the bus with a car battery or a can of gasoline, you should:a) Not allow the rider to get onb) Tell the rider to sit in the...

When you discharge an unruly rider, you should choose a place:

When you discharge an unruly rider, you should choose a place:a) Near a police stationb) That is as safe as possiblec) Convenient for youAnswer: b)...

Which of these statements is true about managing space to the sides of your bus?

Which of these statements is true about managing space to the sides of your bus?a) You should keep your bus to the right side of your laneb) You should...

A hazard is defined as:

A hazard is defined as:a) Another driver onlyb) A condition of the roadway or weather onlyc) Any condition which may cause your trip to be unsafeAnswer: c)...

If you have riders on the bus, you should never fuel your bus:

If you have riders on the bus, you should never fuel your bus:a) Without a fire extinguisher beside youb) In a closed buildingc) With any of the windows...

If your truck's air compressor has its own oil supply, when should you first check the oil level?

If your truck's air compressor has its own oil supply, when should you first check the oil level?a) During your first en route inspectionb) Immediately...

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 to ___ MPH.

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 to ___ MPH.a) 25b)...

Truck and bus parking or emergency brakes must be held on by:

Truck and bus parking or emergency brakes must be held on by:a) Air pressureb) A modulating control valvec) Mechanical forceAnswer: c) Mechanical...

What is emergency controlled braking?

What is emergency controlled braking?a) You apply the brakes as hard as you can without locking the wheelsb) You brake as hard as you can, release the...

The air brake lag distance at 55 MPH on dry pavement adds about ___ feet to your stopping distance.

The air brake lag distance at 55 MPH on dry pavement adds about ___ feet to your stopping distance.a) 12b) 32c) 52Answer: b)...

During normal driving, spring brakes are usually held back by:

During normal driving, spring brakes are usually held back by:a) Boltsb) Spring pressurec) Air pressureAnswer: c) Air press...

The safety valve is usually set to reduce air pressure at ___ psi.

The safety valve is usually set to reduce air pressure at ___ psi.a) 50b) 100c) 150Answer: c) ...

Your truck has a properly functioning dual air brake system and minimum size air tanks. The air pressure should build from 85 to 100 psi within:

Your truck has a properly functioning dual air brake system and minimum size air tanks. The air pressure should build from 85 to 100 psi within:a) 30...

The use of air brakes on a downgrade is only a supplement to the:

The use of air brakes on a downgrade is only a supplement to the:a) Use of the spring brakesb) Use of the front brake limiting valvec) Braking effect...

When you apply the brakes, the brake shoes/linings are pressed against the:

When you apply the brakes, the brake shoes/linings are pressed against the:a) Brake drum or discb) Slack adjusterc) S-camAnswer: a) Brake drum or...

What is emergency stab braking?

What is emergency stab braking?a) Press hard on the brake pedal and apply full hand valve until you stopb) Use light steady pressure on the brake pedalc)...

The application pressure gauge shows how much air pressure you:

The application pressure gauge shows how much air pressure you:a) Have in the air tanksb) Have in the modulating control valvec) Are applying to the brakesAnswer: c)...

The important thing to do when a low air pressure warning comes on is:

The important thing to do when a low air pressure warning comes on is:a) Upshift and drive to a safe placeb) Downshift and drive to a safe placec) Stop...

If your vehicle has an alcohol evaporator, it is there to:

If your vehicle has an alcohol evaporator, it is there to:a) Rid the wet tank of alcohol that condenses and sits at the bottomb) Eliminate the need for...

A truck with air brakes going 55 MPH would require a stopping distance of:

A truck with air brakes going 55 MPH would require a stopping distance of:a) Less than 100 feetb) 100-300 feetc) More than 300 feetAnswer: c) More...

Total stopping distance for vehicles with air brakes is longer than that for vehicles with hydraulic brakes due to ___ distance.

Total stopping distance for vehicles with air brakes is longer than that for vehicles with hydraulic brakes due to ___ distance.a) Brake lagb) Reactionc)...

Excessive use of the service breaks results in overheating, which can lead to:

Excessive use of the service breaks results in overheating, which can lead to:a) Improper adjustment of the S-camb) Increased contact between the brake...

You are driving a new bus with a manual transmission. What gear will you probably have use on a long, steep downhill grade?

You are driving a new bus with a manual transmission. What gear will you probably have use on a long, steep downhill grade?Answer: A lower gear than...

If your trailer doesn't have spring brakes, how should you secure it?

If your trailer doesn't have spring brakes, how should you secure it?A. Only park on level ground.B. Leave the tractor hooked to the trailer.C. Use chock...

What color are the trailer service and emergency air lines?

What color are the trailer service and emergency air lines?A. Blue & GreenB. Red & BlackC. Blue & RedAnswer: C. Blue & ...

After the tractor is pulled to the proper distance in front of the trailer, how do you secure the tractor?

After the tractor is pulled to the proper distance in front of the trailer, how do you secure the tractor?A. As long as the tractor remains in low gear...

When inspecting the trailer supports, you should check for:

When inspecting the trailer supports, you should check for:A. Trailer height.B. Ground support and damage.C. Gravel on the dolly pads.Answer: B....

After unhooking the tractor from the trailer, pull the tractor forward how far?

After unhooking the tractor from the trailer, pull the tractor forward how far?A. Pull tractor completely clear of the trailer.B. Pull the tractor forward,...

If you are dropping a fully loaded trailer, how do you lower the landing gear?

If you are dropping a fully loaded trailer, how do you lower the landing gear?A. Dolly the legs down until they make firm contact with the ground.B. Crank...

You are dropping a trailer and the release arm won't release properly because the locking jaws have too much pressure on them. What should you do?

You are dropping a trailer and the release arm won't release properly because the locking jaws have too much pressure on them. What should you do?A. Pull...

Which of these is a good thing to do when steering to avoid a crash:

Which of these is a good thing to do when steering to avoid a crash:A. Apply the brakes while turning.B. Steer with one hand on the wheel and one hand...

According to accident reports, the vehicle trucks and buses most often collide with is:

According to accident reports, the vehicle trucks and buses most often collide with is:A. The one behind them.B. The one to the right of themC. The one...

Which of these statements about backing a vehicle is true?

Which of these statements about backing a vehicle is true?A. Helpers should be out of the driver's sight and use spoken signals to help the driver.B....

In coupling, when is the trailer height correct?

In coupling, when is the trailer height correct?A. When the trailer landing gear is fully extended.B. When the trailer will be lifted slightly when the...

What is the purpose of the service air line?

What is the purpose of the service air line?A. To service the air control supply.B. To service the tractor air brakes.C. To carry air to the trailer service...

What is off tracking?

What is off tracking?A. Driver failing to keep the truck on route or track.B. The process of taking the tracks of a tractor.C. When the rear wheels follow...

The hand valve should be used:

The hand valve should be used:A. As a parking brake.B. Only with the foot brake.C. To test the trailer brakes.Answer: C. To test the trailer bra...

At what angle do you connect tractor glad hand connections to the trailer?

At what angle do you connect tractor glad hand connections to the trailer?A. 45 degreesB. 60 degreesC. 90 degreesAnswer: C. 90 degr...

How much space should be between the upper and lower fifth wheel plates?

How much space should be between the upper and lower fifth wheel plates?A. About 1 inchB. No more than ½ inchC. NoneAnswer: C. N...

You are driving a combination vehicle when the tractor breaks away and pulls apart the air lines. You would expect the trailer brakes to apply and:

You are driving a combination vehicle when the tractor breaks away and pulls apart the air lines. You would expect the trailer brakes to apply and:A....

When hooking a tractor to a trailer, you'll know the trailer is at the correct height when the:

When hooking a tractor to a trailer, you'll know the trailer is at the correct height when the:A. Kingpin is about 2 ¼ inches above the fifth wheel.B....

After hooking up, you should check the fifth wheel connection by:

After hooking up, you should check the fifth wheel connection by:A. Driving away at 20 mph and pulling down the trailer hand valve.B. Backing up with...

If the service line disconnects while you are driving, what will happen right away?

If the service line disconnects while you are driving, what will happen right away?A. The emergency tractor brakes will come on.B. The emergency trailer...

During normal driving, some drivers use the trolley (hand) valve before the brake pedal in order to prevent trailer skids. Which of the following statements is true?

During normal driving, some drivers use the trolley (hand) valve before the brake pedal in order to prevent trailer skids. Which of the following statements...

Air brake equipped trailers made before 1975:

Air brake equipped trailers made before 1975:A. Usually do not have spring brakes.B. Usually need a glad hand converter.C. Cannot be operated on interstate...

After coupling a semi-trailer, you should crank the front trailer supports how high?

After coupling a semi-trailer, you should crank the front trailer supports how high?A. Raised ½ way with the crank handle secured.B. Raised ¾ way with...

If the fifth wheel locking lever is not locked after the jaws close around the kingpin:

If the fifth wheel locking lever is not locked after the jaws close around the kingpin:A. The trailer will not swing on the fifth wheel.B. The hand valve...

With the engine off, the brakes released and your foot on the brake pedal, a combination vehicle air brake system should not leak more than how many psi in 1 minute?

With the engine off, the brakes released and your foot on the brake pedal, a combination vehicle air brake system should not leak more than how many psi...

There are two things that a driver can do to prevent a rollover. They are (1) keep the cargo as close to the ground as possible, and:

There are two things that a driver can do to prevent a rollover. They are (1) keep the cargo as close to the ground as possible, and:A. Make sure the...

After pushing in the trailer supply valve, you should not move the tractor until the air system is:

After pushing in the trailer supply valve, you should not move the tractor until the air system is:A. ChargingB. At normal pressureC. Between 50 and 60...

You are hooking a tractor to a semi-trailer and have backed up but are not under it. What should you do before backing under the trailer?

You are hooking a tractor to a semi-trailer and have backed up but are not under it. What should you do before backing under the trailer?A. Hook up the...

The safety latch for the fifth wheel locking lever must be ____ for the coupling to be correct.

The safety latch for the fifth wheel locking lever must be ____ for the coupling to be correct.A. Over the locking lever.B. Straight up.C. Through the...

The front trailer supports are up and the trailer is resting on the tractor. Make sure:

The front trailer supports are up and the trailer is resting on the tractor. Make sure:A. There is enough clearance between the upper and lower fifth...

You supply air to the trailer tanks by:

You supply air to the trailer tanks by:A. Pushing in the trailer air supply valve.B. Pulling out the trailer air supply valve.C. Connecting the service...

A driver crosses the airlines when hooking up to an old trailer. What will happen?

A driver crosses the airlines when hooking up to an old trailer. What will happen?A. The hand valve will apply the tractor brakes instead of the trailer...

When should you use the hand valve to park a combination vehicle?

When should you use the hand valve to park a combination vehicle?A. To park at loading docks.B. To park on a grade.C. Never.Answer: C. Nev...

To unlock the fifth wheel, pull the release handle to the ____position.

To unlock the fifth wheel, pull the release handle to the ____position.A. OpenB. NeutralC. ClosedAnswer: A. O...

Why should you lock the tractor glad hands to each other (or dummy couplers) when you are not towing a trailer?

Why should you lock the tractor glad hands to each other (or dummy couplers) when you are not towing a trailer?A. The connected brake circuit becomes...

The best way to tell if your trailer has started to skid is to:

The best way to tell if your trailer has started to skid is to:A. Hear the tires skidding.B. See it in your mirrors.C. Feel the "pulling" in the cab.Answer: B....

When you get ready to back under a semi-trailer, you should line up:

When you get ready to back under a semi-trailer, you should line up:A. The kingpin to engage the driver's side locking jaw first.B. Directly in front...

Loss of air pressure in the emergency line causes:

Loss of air pressure in the emergency line causes:A. The relay valves to close.B. An increase in air pressure to the service line.C. The trailer's emergency...

If the spring brakes don't release when you push the trailer air supply control valve, you should:

If the spring brakes don't release when you push the trailer air supply control valve, you should:A. Check the air line connections.B. Cross the air lines.C....

A trailer is most likely to jackknife when it is ____.

A trailer is most likely to jackknife when it is ____.A. Loaded to full capacity.B. Overloaded.C. EmptyAnswer: C. Em...

When checking that the trailer is securely coupled to the tractor, the landing gear should be:

When checking that the trailer is securely coupled to the tractor, the landing gear should be:A. Fully raised.B. Slightly raised.C. Fully lowered.Answer: B....

Which part of the kingpin should the locking jaws close around?

Which part of the kingpin should the locking jaws close around?A. The shank.B. The head.C. The base.Answer: A. The sha...

When coupling, the proper position of the fifth wheel is:

When coupling, the proper position of the fifth wheel is:A. Level with the ground.B. Tilted up towards the end of the tractor.C. Tilted down toward the...

The trailer air supply control valve should automatically close when the air pressure falls to between ____psi.

The trailer air supply control valve should automatically close when the air pressure falls to between ____psi.A. 100 and 125.B. 60 and 85.C. 20 and 45.Answer: C....