Minnesota DVS CDL General Knowledge Practice Test 7

  • Questions50
  • Correct to pass40
  • Passing score80%
  • Minimum age18 years

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

  1. 1. A doctor prescribes you a medicine that can cause drowsiness. What should you do?

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    Answer A: Tell the doctor what you drive and not drive while affected

    Both prescription and over the counter medicines can make a driver unsafe, so the medical professional must know the job and the driver must stay out of the seat while affected.

  2. 2. A tire has a cut deep enough to expose the body ply or the belt material. What does that mean?

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    Answer D: The vehicle must not be driven on that tire

    Once the structural plies are exposed the casing has lost its strength, and federal rules treat that tire as unfit for the road.

  3. 3. Under federal rules, what happens to a commercial driver found with any detectable amount of alcohol while operating a commercial vehicle?

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    Answer D: The driver is placed out of service for 24 hours

    Any measurable alcohol takes a commercial driver off the road for 24 hours, and a concentration of 0.04 percent or more brings a disqualification.

  4. 4. You find a defect during the pre-trip inspection. What must happen before the vehicle is driven?

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    Answer C: It must be repaired, or the vehicle must not be driven

    Writing a defect down does not make the vehicle safe; a defect that affects safe operation has to be corrected before the trip starts.

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

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    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.

  6. 6. How are the headlights, marker lights and turn signals checked during the seven-step inspection?

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    Answer A: The engine is shut off, the parking brake is set, the lights are switched on and then checked from outside the vehicle

    The lights are switched on with the vehicle secured, then the driver walks around and confirms each lamp actually works and is clean.

  7. 7. What are you checking when you pull the engine oil dipstick during the pre-trip?

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    Answer A: That the oil level is within the safe operating range marked on the stick

    The dipstick shows whether there is enough oil to lubricate and cool the engine, and a level outside the safe range must be corrected before driving.

  8. 8. How is free play in the steering wheel measured during the inspection?

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    Answer B: By turning the wheel until the front wheels just start to move and noting the movement

    Play is the movement at the rim that produces no movement at the road wheels, so it is measured by turning until the wheels first respond.

  9. 9. 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?

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    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.

  10. 10. The coolant temperature gauge climbs above its normal range on a long grade. What is the correct response?

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    Answer C: Stop when it is safe to do so and find the cause before going on

    Rising coolant temperature signals a fault such as a lost belt, a leak or a blocked radiator, and continuing can turn a repair into a destroyed engine.

  11. 11. When turning left, what should a driver of a long vehicle do before beginning the turn?

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    Answer B: Reach the center of the intersection so the rear wheels clear the corner

    The rear wheels follow a tighter path than the front, so the vehicle must reach the center of the intersection before the turn begins.

  12. 12. You are told a posted bridge ahead has a weight limit lower than your gross weight. What must you do?

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    Answer C: Take a route that avoids it, because a posted limit is a legal limit

    A posted structure limit must be obeyed exactly as any other weight limit, so a heavier vehicle has to be routed around it.

  13. 13. You have finished a lane change in a vehicle whose turn signal does not cancel by itself. What must you do?

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    Answer D: Turn the signal off yourself

    A signal left running tells other drivers you are about to move again, and they may act on that false information.

  14. 14. Which brake lining condition must be reported?

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    Answer C: Linings that are worn thin, loose, cracked or soaked with oil or grease

    Linings must have enough material left and must be securely attached and clean, because a thin, loose or contaminated lining cannot deliver its share of braking.

  15. 15. You are on a freeway and see brake lights come on in several vehicles far ahead of you. What should you do?

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    Answer A: Ease off the accelerator and get ready to slow down

    Brake lights well ahead are an early warning that traffic is slowing, and acting on them gives a heavy vehicle the room it needs.

  16. 16. You normally pull an empty trailer, but today the same tractor is loaded to its legal maximum. What changes about getting under way?

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    Answer A: You may need to start in a lower gear, since the load takes more pulling power

    The heavier the load, the lower the gear needed to get the vehicle rolling without lugging or stalling the engine.

  17. 17. On packed snow, how much should a commercial driver reduce speed?

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    Answer D: By about one half or more

    Packed snow costs far more traction than rain, so speed should be cut by half or more.

  18. 18. Why is a quick lane change particularly risky with a load of hanging meat or of livestock?

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    Answer A: The load swings or leans and can keep pushing the trailer after you straighten out

    A swinging or leaning load keeps moving after the vehicle has finished the maneuver, so its momentum acts on the trailer at the worst moment.

  19. 19. When is a road surface usually most slippery during a rain shower?

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    Answer A: Just after the rain starts, when water mixes with oil and dirt on the surface

    The first rain lifts oil and dust into a slick film that has not yet been washed away, so the road is more slippery than it will be later.

  20. 20. You are entering a freeway from a short ramp with a fully loaded trailer. What should you do?

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    Answer A: Begin building speed early and wait for a large gap

    A loaded vehicle accelerates slowly, so it needs both a running start and a much larger gap than a car would use.

  21. 21. Under federal safety rules, what must the driver of a commercial vehicle do before starting a trip?

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    Answer A: Be satisfied that the vehicle is in safe operating condition

    The driver is responsible for inspecting the vehicle and must be satisfied it is in safe operating condition before the trip begins.

  22. 22. What does the suspension system weight rating tell the driver?

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    Answer A: The maximum weight that the manufacturer says the suspension can carry

    Like tires and axles, suspensions have a manufacturer capacity, and loading beyond it can damage springs and air bags.

  23. 23. A hard frost has left your vehicle covered in ice. What must be cleared before you drive?

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    Answer D: The windshield, mirrors, lights and reflectors

    You must be able to see out and other drivers must be able to see your lights and reflectors, so all of those surfaces have to be cleared.

  24. 24. You have just passed another vehicle on a two lane road. What tells you it is safe to return to your lane?

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    Answer B: You can see the whole front of that vehicle in your right mirror

    Seeing the entire front of the vehicle you passed in your mirror proves you are far enough ahead to move back over without cutting the driver off.

  25. 25. What is the correct way to make a normal stop?

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    Answer A: Push the brake pedal down gradually and bring the vehicle to a smooth stop

    Steady, progressive pedal pressure keeps the vehicle stable and lets the driver behind you react to a predictable slowdown.

  26. 26. What is the purpose of the header board, or headache rack, that you inspect behind the cab?

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    Answer A: It protects the driver from cargo that shifts forward during a hard stop

    In a hard stop the load keeps moving forward, and the header board is the barrier between that load and the back of the cab.

  27. 27. You miss a gear while double clutching and the transmission is stuck in neutral. What should you do?

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    Answer B: Return to neutral, release the clutch, bring engine speed to match road speed and try again

    Forcing the lever damages the gears; matching the engine speed to the road speed lets the gear engage cleanly on the next try.

  28. 28. Which lights should be used in fog, by day or by night?

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    Answer A: Low beams and fog lights, together with the four-way flashers

    High beam light bounces back off the water droplets and makes seeing worse, while low beams, fog lights and flashers help you see and help others see you.

  29. 29. While you are driving, what should you do to catch a developing problem with the vehicle?

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    Answer A: Check the gauges regularly and pay attention to unusual sounds, smells or vibrations

    Inspection continues during the trip: gauges, mirrors and your senses can reveal a problem long before a warning light does.

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

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    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.

  31. 31. What alcohol concentration makes it a crime to drive a commercial motor vehicle in Minnesota?

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    Answer B: 0.04 or more

    Minnesota Statutes 169A.20 sets the commercial motor vehicle threshold at 0.04, half of the limit that applies to other drivers.

  32. 32. The brake pedal goes to the floor in a vehicle with hydraulic brakes. What can you do to build some braking pressure?

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    Answer B: Pump the brake pedal rapidly, which may bring back enough pressure to slow the vehicle

    Pumping can restore some hydraulic pressure; along with downshifting and the parking brake it is one of the ways to stop when the pedal fails.

  33. 33. A delivery van is stopped in the right lane ahead with its flashers on. What should you expect?

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    Answer C: Someone may step into your lane from in front of it

    A stopped delivery vehicle hides the space in front of it, and that is exactly where a person carrying a package is likely to walk out.

  34. 34. Your axle weights are legal, but the tires on that axle are rated below the weight it is carrying. What controls?

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    Answer B: The lower figure, so the tires may not be loaded beyond their marked rating

    You may never exceed the rating marked on a tire, even when the axle limit would allow more, because an overloaded tire builds heat and can fail.

  35. 35. What is a bulkhead in a cargo body used for?

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    Answer D: To divide the space and stop cargo from moving into another part of the body

    A bulkhead is a solid partition that separates one part of the load space from another and blocks the cargo from moving past it.

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

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    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.

  37. 37. Federal rules require a power unit that is not carrying placarded hazardous materials to have a fire extinguisher with which minimum rating?

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    Answer A: One rated 5 B:C or more, or two rated 4 B:C or more each

    The minimum is a single unit rated 5 B:C or more, or two units of at least 4 B:C each, which is enough to attack a fuel or electrical fire.

  38. 38. During a stop you find a package in the trailer leaking an unknown chemical. What should you do?

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    Answer C: Keep clear, keep others away and get help without touching the package

    A driver without the training and equipment does not handle a leak; the job is to protect people from the material and get qualified help to the scene.

  39. 39. A carrier operates commercial vehicles every day of the week. What weekly on-duty limit applies to its drivers?

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    Answer A: 70 hours in 8 consecutive days

    The limit is 60 hours in 7 consecutive days for a carrier that does not run every day, and 70 hours in 8 consecutive days for one that does.

  40. 40. Your speedometer stops working during the pre-trip check. How should it be treated?

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    Answer D: As a defect, because the driver cannot judge and control speed without it

    A working speedometer is required equipment, because judging speed by feel in a heavy vehicle is unreliable and speed governs stopping distance.

  41. 41. How soon must warning devices be placed after a commercial vehicle stops on the traveled part or the shoulder of a highway?

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    Answer D: As soon as possible and in any case within 10 minutes

    The hazard warning flashers go on immediately and the warning devices must be in place as soon as possible, never later than 10 minutes after stopping.

  42. 42. Where should a driver expect fog to form first?

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    Answer D: In low ground, near water and in valleys

    Cool moist air settles in low places, so fog patches appear in hollows, river valleys and near lakes before they appear anywhere else.

  43. 43. Under the federal air brake standard, the low air pressure warning must come on before reservoir pressure drops below what level?

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    Answer A: Before pressure falls below 60 psi

    Federal Motor Vehicle Safety Standard 121 requires the warning to operate while service reservoir pressure is still above 60 psi, which leaves enough air to bring the vehicle to a normal stop.

  44. 44. Cargo carried inside the cab must never do which of these?

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    Answer C: Block the driver view, restrict arm or leg movement, or block an emergency exit

    Anything inside the cab must leave the driver a clear view, free movement of the arms and legs, and an unobstructed way out of the vehicle.

  45. 45. What condition should the fifth wheel be in before you back under a trailer?

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    Answer C: Jaws open, plate greased, and the fifth wheel tilted down toward the rear

    The jaws have to be open to take the kingpin, the plate must be lubricated to prevent hard steering, and the fifth wheel is tilted down at the rear so the trailer apron can ride up onto it.

  46. 46. You are the first to arrive at a crash. What is the correct order of actions?

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    Answer C: Protect the area, notify the authorities, care for the injured

    Preventing a second crash comes first, because an unprotected scene puts the injured and the helpers in more danger than the original collision.

  47. 47. Which drivers does Minnesota exempt from the requirement to hold a commercial driver's license?

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    Answer A: Farm truck drivers operating within 150 miles of the farm

    Minnesota waives the CDL requirement for qualifying farm trucks used within 150 miles of the farm, along with authorized emergency vehicles and recreational vehicles used for personal purposes.

  48. 48. You pick up a trailer that another driver dropped in the yard. What must you do before pulling it?

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    Answer B: Inspect it yourself, because you are responsible for the whole vehicle you drive

    Responsibility follows the driver who moves the vehicle, and a trailer that has stood in a yard may have lost air, developed a flat tire or been damaged.

  49. 49. When should a driver select the gear for a long, steep downgrade?

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    Answer B: Before starting down the grade

    The low gear has to be chosen before the descent, because a heavy vehicle gaining speed may refuse to shift down at all.

  50. 50. Cargo securement must be strong enough to hold the load under which conditions?

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    Answer A: Hard braking, hard acceleration and hard turning, as well as the bouncing of the road

    The securement standard is written around the forces of a hard stop, a hard start, a hard turn and vertical movement on a rough surface, all of which occur in ordinary driving.