Hawaii HDOT MVSO CDL General Knowledge Practice Test 6

  • Questions50
  • Correct to pass40
  • Passing score80%
  • Minimum age21 years

50 questions. Pick an answer to see if it is right and why; you need 40 correct answers to pass.

  1. 1. The paperwork shows a weight, but the load looks heavier than you expected. What should you do?

    Show answer

    Answer C: Weigh the vehicle, since you are the one answerable for driving it overweight

    The driver is the one who can be cited for an overweight vehicle, so a doubtful weight is settled on a scale before the trip continues.

  2. 2. Which set of maneuvers makes up the basic control skills part of the commercial driving test?

    Show answer

    Answer D: Straight line backing, offset backing, parallel parking and alley docking

    The basic control skills test is carried out off the road and consists of low speed exercises such as straight line backing, offset backing, parallel parking and the alley dock.

  3. 3. You are stopped in traffic on a steep upgrade behind another truck. How much space should you leave in front?

    Show answer

    Answer A: Enough that you can pull away without rolling back into the vehicle behind you

    Room ahead lets you get moving smoothly on a grade instead of having to hold the vehicle perfectly still or roll back toward the traffic behind.

  4. 4. How long must a motor carrier keep a driver vehicle inspection report and the certification of repairs?

    Show answer

    Answer B: Three months

    The original report and the certifications attached to it are kept on file for three months from the date the report was prepared.

  5. 5. Which clues warn you that a parked car may pull out or open a door?

    Show answer

    Answer A: Exhaust smoke, turned front wheels, a person in the seat

    Signs of life in a parked vehicle, such as a running engine, turned wheels or an occupant, mean it may move or open a door into your path.

  6. 6. What is the purpose of an escape ramp on a mountain grade?

    Show answer

    Answer C: To stop a runaway vehicle without injuring the driver

    Escape ramps use soft material or a steep upgrade to bring a vehicle with failed brakes to a controlled stop.

  7. 7. Besides slowing down, which technique most reduces the risk of a skid on a snow covered road?

    Show answer

    Answer B: Make every steering, braking and speed change gradual

    Traction is limited on snow, and sudden inputs demand more grip than the surface can supply, so smoothness is what keeps the tires attached to the road.

  8. 8. Which document must be available to show that the annual inspection was carried out?

    Show answer

    Answer C: The inspection report or a copy of it, or a decal displayed on the vehicle

    Proof of the periodic inspection travels with the vehicle, either as the report itself or as the decal fixed where an inspector can see it.

  9. 9. Why is a leaking exhaust system on a commercial vehicle dangerous to the driver?

    Show answer

    Answer B: It can let carbon monoxide reach the cab, where it can poison the occupants

    Exhaust gas contains carbon monoxide, which has no smell and dulls the driver judgment long before it becomes obvious that anything is wrong.

  10. 10. Why does a load need to be balanced from side to side?

    Show answer

    Answer B: Because a heavy side raises the rollover risk and can overload the tires and springs on that side

    An uneven load tips the balance of the vehicle in curves and pushes the tires and suspension on the loaded side past their rating.

  11. 11. In hazard perception, what counts as a hazard?

    Show answer

    Answer C: Any road user or condition that could become a danger

    A hazard is anything with the potential to create danger, which is why drivers are taught to spot them early rather than react to emergencies.

  12. 12. The scale shows that your combination is over the legal gross weight. Why will sliding the tandems not fix it?

    Show answer

    Answer B: Because sliding the axles changes where the weight sits, not how much there is

    Repositioning axles redistributes weight between axle groups; when the total is too high, freight has to come off the vehicle.

  13. 13. Before starting a trip, what must the driver confirm about the weight of the loaded vehicle?

    Show answer

    Answer A: That it is within the legal gross and axle limits for the route being driven

    Overweight vehicles brake poorly, damage tires and suspension components, and can be put out of service at a scale, so weight is checked before the wheels turn.

  14. 14. You are pulling away from a curb in a 65 foot combination. Besides traffic, what must you watch?

    Show answer

    Answer B: The trailer wheels, which stay close to the curb and can strike it or an object on it

    Because of off-tracking, the rear wheels follow a tighter path than the front, so they stay near the curb while the cab is already out in the lane.

  15. 15. What tells you that an air suspension bag has a problem?

    Show answer

    Answer B: The bag is leaking or damaged, or the vehicle sits unevenly on that side

    An air bag that leaks or is cut lets that corner of the vehicle settle, which throws the load onto the other suspension parts and changes the ride height.

  16. 16. Under federal rules, which commercial vehicles must stop at every railroad crossing before proceeding?

    Show answer

    Answer D: Passenger buses and placarded hazardous materials vehicles

    Buses carrying passengers and vehicles required to display hazardous materials placards must stop at crossings, while other commercial vehicles slow and check.

  17. 17. What must be checked on a sliding fifth wheel during the inspection?

    Show answer

    Answer B: That it is locked in position and not so far forward that the trailer can hit the cab

    A slider that is unlocked can move under braking, and one set too far forward lets the trailer strike the cab when the tractor turns sharply.

  18. 18. How does a typical escape ramp stop a runaway vehicle?

    Show answer

    Answer B: With a bed of loose gravel or sand, often on an upgrade

    Escape ramps use deep loose material, usually combined with a rising grade, so the vehicle is slowed gradually instead of being stopped by impact.

  19. 19. Your vehicle stalls on a railroad crossing and a train is coming. What should you do?

    Show answer

    Answer C: Get out at once and move toward the train, well off to one side

    Leave the vehicle immediately and move at an angle toward the oncoming train, so that wreckage thrown forward by the impact travels away from you.

  20. 20. What does a front-end header board on a van or flatbed protect against?

    Show answer

    Answer A: Cargo moving forward toward the cab in a crash or hard stop

    The header board, often called a headache rack, blocks forward movement of the load toward the driver.

  21. 21. The only way into a customer yard forces you to back toward the right, or blind, side of the vehicle. What should you do?

    Show answer

    Answer D: Use a helper and get out to check the path more often than you normally would

    Blind side backing is allowed but far riskier, so it calls for a spotter you can see and for repeated checks of the path on foot.

  22. 22. Why should a retarder be switched off when the road is wet, icy or snowy?

    Show answer

    Answer C: It can make the drive wheels skid when traction is poor

    A retarder slows the drive wheels only, and on a slippery surface that braking force can break their traction and start a skid.

  23. 23. In very hot weather, how often should you check the tires during a trip?

    Show answer

    Answer D: About every two hours or every 100 miles

    Heat raises tire pressure and can lead to blowouts, so tires are checked about every two hours or 100 miles when it is very hot.

  24. 24. What is generally the safest speed in dense but freely moving highway traffic?

    Show answer

    Answer D: The speed of the traffic around you, up to the posted limit

    Crashes rise with the difference between your speed and the traffic around you, so moving with the flow within the legal limit is safest.

  25. 25. A sign before a long descent shows 6 percent. What does that number tell you?

    Show answer

    Answer A: How steep the grade ahead is

    Percent grade is the drop in feet for every hundred feet of road, so the higher the number the faster speed will build and the lower the gear you need.

  26. 26. At a stop on a hot day you find a tire that is too hot to touch. What should you do?

    Show answer

    Answer C: Wait until the tire cools before driving on, and do not let air out of it

    A tire that is too hot to touch may be about to fail or catch fire; releasing air only leaves it underinflated once it cools, which makes things worse.

  27. 27. A vehicle carries placards on its front, rear and both sides. What is the main purpose of those placards?

    Show answer

    Answer C: To tell emergency responders and other people what hazard the cargo presents

    Placards warn everyone around the vehicle, especially emergency responders, about the kind of hazard the cargo presents.

  28. 28. You are about to cross a long, high bridge with a light load in gusty wind. What should you do?

    Show answer

    Answer C: Slow down and be ready for a sudden push

    Wind is strongest where a bridge leaves the shelter of the land, and lower speed gives you time to correct when the first gust hits.

  29. 29. When should mirror adjustment be checked, and what should each mirror show?

    Show answer

    Answer B: Before every trip, with each mirror adjusted to show some part of the vehicle

    Checking the mirrors before each trip and keeping a small part of the vehicle in view gives a reference point for judging distance behind and beside you.

  30. 30. An intermodal container is being carried on an ordinary flatbed rather than on a container chassis. What does that mean for securement?

    Show answer

    Answer B: It must be secured with tiedowns that meet the container securement requirements

    A container carried on a vehicle that is not fitted with integral locking devices has to be secured to the deck with tiedowns that satisfy the rules for containers.

  31. 31. Apart from the legal duty, what is the main practical reason for a thorough pre-trip inspection?

    Show answer

    Answer A: It finds problems that could cause a breakdown or a crash before the vehicle is on the road

    A defect found in the yard is an inconvenience, while the same defect found at highway speed can be a crash, so the inspection is where problems are cheapest to fix.

  32. 32. What is the payload of a truck?

    Show answer

    Answer C: The weight of the cargo the vehicle is carrying, that is the loaded weight less the empty weight

    Payload is what is left of the legal or rated weight once the weight of the empty vehicle is taken off, and it is the weight of cargo that can be carried.

  33. 33. A car ahead of you keeps drifting within its lane and moving unevenly. What should you assume?

    Show answer

    Answer C: The driver may be distracted, lost or impaired

    Unsteady lane keeping is a classic clue to a driver who is not in full control, so the safe response is to keep back and give plenty of room.

  34. 34. You have a part load that fills only a third of a long trailer. How should it be placed?

    Show answer

    Answer C: Spread out and centerd side to side, so the weight sits over the axles

    A part load is spread over as much of the floor as possible and kept centerd, so no axle is overloaded and the vehicle stays balanced from side to side.

  35. 35. How does a load carried high in the trailer affect safe speed through a curve?

    Show answer

    Answer B: It raises the rollover risk, so the speed must be lower

    A high center of gravity lets the vehicle tip long before the tires lose their grip, so height of the load directly limits curve speed.

  36. 36. Your truck has a backup alarm that sounds whenever reverse is selected. What may a driver rely on it for?

    Show answer

    Answer D: Very little; it warns some people but cannot show you what is behind the vehicle

    An alarm may not be heard over yard noise or by someone wearing hearing protection, so it never replaces looking at the path yourself.

  37. 37. How long must the record of a periodic inspection be kept?

    Show answer

    Answer A: Fourteen months

    The periodic inspection report is retained for fourteen months from the date of the report, which covers the full twelve month cycle plus a margin.

  38. 38. You have backed into the same loading bay every week for a year. How often should you still get out and walk to the rear before backing?

    Show answer

    Answer D: Every time, since the area can change while you are away from it

    A familiar space is no guarantee; vehicles, pallets, people and overhead obstructions appear between one visit and the next, so you check on every occasion.

  39. 39. During uncoupling, when may the fifth wheel locking lever be released?

    Show answer

    Answer D: Only after the landing gear is down and taking the weight of the trailer

    The landing gear has to be supporting the trailer before the lock is released; otherwise the trailer nose can drop as soon as the tractor pulls out.

  40. 40. Why is backing toward the driver side preferred?

    Show answer

    Answer C: You can watch the rear of the vehicle directly through the side window

    Backing to the left lets the driver look out the window and see the rear of the vehicle directly instead of relying on a mirror alone.

  41. 41. The shipper hands you the placards for a load that needs them. Who puts them on the vehicle?

    Show answer

    Answer C: The driver, who must also make sure they are the correct ones and are readable

    The shipper supplies the placards, but it is the driver who must place them on the vehicle and confirm that they match the load and can be read.

  42. 42. Does the federal texting ban apply to a company dispatching device mounted in the cab?

    Show answer

    Answer B: Yes, entering or reading text on it while driving is banned

    The rule is written around the act of reading or entering text on any electronic device, not around who owns the device.

  43. 43. How should the steering wheel be held when driving a large vehicle?

    Show answer

    Answer D: Firmly with both hands, placed on opposite sides of the wheel

    Both hands on opposite sides give the leverage and control needed if a tire drops off the pavement or the wheel is jolted.

  44. 44. After two hours of driving you measure a tire and the pressure reads higher than the cold figure. What should you do?

    Show answer

    Answer B: Nothing, because pressure rises normally as a tire heats up in use

    Air expands as the tire heats, so a higher hot reading is expected, and letting air out leaves the tire underinflated once it cools.

  45. 45. You press on a drive belt and it deflects far more than the others. What does that suggest?

    Show answer

    Answer C: The belt is too loose and the part it drives may not work properly

    A belt with excessive play slips on its pulleys, so the accessory it drives turns too slowly or not at all under load.

  46. 46. What color must the clearance and side marker lamps and reflectors at the front of a trailer be?

    Show answer

    Answer A: Amber

    Amber marks the front and the forward part of the sides of a vehicle, while red marks the rear, so another driver can tell which way the vehicle is facing.

  47. 47. What should you check about the fuel tank during the walkaround?

    Show answer

    Answer A: That it is securely mounted, the cap is on tight and there are no leaks

    A loose tank or a missing cap can spill fuel, and any fuel leak is a fire hazard that makes the vehicle unsafe to drive.

  48. 48. As a long vehicle goes around a corner, how do the rear wheels travel compared with the front wheels?

    Show answer

    Answer A: They follow a tighter path, closer to the inside of the turn

    The rear wheels off-track toward the inside of the turn, and the longer the vehicle the bigger the difference, which is why the front must swing wide enough to keep the rear off the curb.

  49. 49. What is the basic rule about backing a large vehicle?

    Show answer

    Answer B: Avoid backing whenever there is another way

    Backing is dangerous because you cannot see everything behind you, so the manual tells drivers to plan routes and parking that avoid it.

  50. 50. Which vehicle condition makes hydroplaning more likely?

    Show answer

    Answer C: Tires that are worn or underinflated

    Tread depth and correct pressure are what let a tire push water aside, so worn or soft tires lift onto the water film at lower speeds.