Wisconsin WisDOT DMV CDL General Knowledge Practice Test 1

Test 1 of 5. Pick an answer for each question to see if it is right and why; your score appears at the end. You need 40 correct answers to pass, the same ratio as the real Wisconsin test.

A country road through dairy farmland with red barns, a typical landscape of Wisconsin
  1. 1. 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.

  2. 2. Within what distance should high beams be lowered at night?

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    Answer D: Within about 500 feet of an oncoming vehicle and within about 500 feet of a vehicle you are following

    High beams blind other drivers at close range, so they are lowered at roughly the same distance whether the other vehicle is coming toward you or is ahead of you.

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

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    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.

  4. 4. Your load projects more than 4 feet beyond the rear of the vehicle. How must the projecting end be marked?

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    Answer A: With a red or orange flag by day and a red lamp after dark

    Federal rules require a warning flag on a rear projecting load in daylight and a red lamp on the end of it when lights are required.

  5. 5. In the seven-step method, what comes immediately after starting the engine and inspecting inside the cab?

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    Answer D: Turn off the engine and check the lights

    Step four shuts the engine down and switches on the lamps needed for driving so the driver can leave the cab and confirm they actually work.

  6. 6. Why does the manual insist on a firm grip with both hands on opposite sides of the steering wheel?

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    Answer A: A hard bump can pull the wheel out of a loose grip

    Hitting a curb or a deep pothole can jerk the wheel violently, and only a firm two-handed grip keeps the vehicle under control when that happens.

  7. 7. 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.

  8. 8. You are making a right turn and cannot complete it without swinging into the oncoming lane. An oncoming car is approaching. What should you do?

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    Answer A: Wait and let the oncoming vehicle pass before completing the turn, and do not back up

    The oncoming vehicle has the lane; backing up in traffic is dangerous, so hold your position and finish the turn once the way is clear.

  9. 9. Why is a leak in the exhaust system especially dangerous in cold weather?

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    Answer A: Carbon monoxide can build up inside a closed cab

    In winter the windows are shut and the heater is running, so exhaust gas that escapes early can reach the driver and cause drowsiness or worse.

  10. 10. An overpass you have driven under before now has a fresh layer of pavement on the road below it. Why does that matter?

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    Answer B: The new layer raises the road and reduces the clearance

    Repaving lifts the road surface, so the real clearance under a structure can be less than the height posted on it.

  11. 11. Which items belong to the in-cab part of the inspection?

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    Answer D: Gauges, controls, mirrors, windshield, wipers, horn, heater and defroster

    The in-cab step checks the instruments and controls the driver depends on, along with mirrors, glass, wipers, horn and the heater and defroster.

  12. 12. A veteran left military service and wants to use Wisconsin's CDL skills test waiver. How long after separation can they still use it, and is the knowledge test also waived?

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    Answer C: One year after separation, and the applicant must still pass the knowledge test

    Wisconsin limits the military CDL skills test waiver to current members and those within one year of separation or retirement, and applicants must still pass the knowledge test.

  13. 13. You are hauling livestock and the trailer is only partly full. What should be done?

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    Answer A: Use false bulkheads or partitions to keep the animals bunched together

    Animals that can move around shift the center of gravity, so a partial load is bunched together with partitions to limit how far the weight can move.

  14. 14. Why must exhaust components be checked for contact with other parts of the vehicle?

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    Answer B: Hot exhaust parts touching fuel lines, tires or wiring can start a fire

    Exhaust pipes run hot enough to ignite fuel and melt insulation, so they must be kept clear of the fuel system, the tires and the electrical harness.

  15. 15. Loading heavy freight on top of lighter freight has what effect on the vehicle?

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    Answer B: It raises the center of gravity and makes a rollover more likely

    A high center of gravity lets the vehicle tip more easily in curves or during a sudden swerve.

  16. 16. What is the best practice when fog is thick enough to hide the road ahead?

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    Answer B: Slow down before entering the fog, and if visibility is too poor, pull off into a rest area or truck stop until it improves

    The safest choice in heavy fog is not to be driving in it, and if you are already in it your speed has to come down before your visibility does.

  17. 17. What is wrong with resting your foot on the clutch pedal between shifts?

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    Answer B: It slowly wears the clutch out, because the pressure plate is never fully engaged

    Any weight on the pedal partly disengages the clutch, so it slips and wears; the foot belongs off the pedal once the shift is finished.

  18. 18. You are backing a tractor-trailer in a straight line and the trailer starts to drift to the left. What is the standard correction?

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    Answer D: Turn the top of the steering wheel a little to the left, toward the drift

    Small corrections made in the direction the trailer is drifting bring it back into line; large or opposite movements make the drift worse.

  19. 19. How does a Wisconsin OWI conviction affect a CDL holder beyond the standard penalties, even for a first offense?

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    Answer D: It adds a 1-year CDL disqualification, or 3 years if the vehicle was hauling hazardous materials

    Wisconsin adds a 1-year CDL disqualification for an OWI conviction, extended to 3 years if the driver was transporting hazardous materials at the time.

  20. 20. Why should the mirrors be checked repeatedly while you make a tight turn?

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    Answer C: To watch the rear of the vehicle clear other vehicles and objects

    In a long vehicle the rear wheels cut inside the path of the front wheels, so only the mirrors show whether the rear is clearing curbs, poles and other vehicles.

  21. 21. What must a Wisconsin applicant already hold before a school bus S endorsement can be added to it?

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    Answer B: A Commercial Driver License

    Wisconsin requires an applicant to already hold a Commercial Driver License before a school bus S endorsement can be added, along with a specific physical examination.

  22. 22. How does overloading affect the way a vehicle drives?

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    Answer C: It slows the vehicle on upgrades, makes stopping take longer and can overheat the brakes on downgrades

    Extra weight demands more from the engine and the brakes, so the vehicle climbs slowly and needs much more distance to stop.

  23. 23. What is the overall range of possible Wisconsin CDL disqualification periods, depending on the violation?

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    Answer B: 60 days to a lifetime

    Wisconsin describes CDL disqualification periods as running from a minimum of 60 days up to a lifetime, depending on the number, type, and severity of the violation.

  24. 24. Where is the yellow antilock brake malfunction lamp on a trailer, and what does it mean if it stays lit?

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    Answer D: On the left side, at the front or rear corner, and it means the antilock function may not be working

    Trailers carry the yellow lamp on the left side, and a lamp that stays on after the bulb check means the antilock function may be lost even though the normal brakes still work.

  25. 25. Which of these is a major cause of skids in heavy vehicles?

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    Answer C: Over-braking, over-steering, over-acceleration or driving too fast for conditions

    Skids happen when the tires are asked for more grip than the road can give, which happens through braking, steering or accelerating too hard or simply too much speed.

  26. 26. You are hauling an open box of loose gravel. What does that load require?

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    Answer A: A cover, so that material cannot blow off or spill onto the road

    Loose material that can be blown or spilled has to be covered so it does not come out of the body and strike traffic behind.

  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. Part of your load stands high enough to hide a rear lamp or a reflector. What must be done?

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    Answer B: The load must be moved or extra lamps fitted so the required lights can be seen

    Required lamps and reflectors must remain visible; if the cargo blocks them, the load is rearranged or additional lamps are fitted so the vehicle can still be seen.

  29. 29. What actually lowers the amount of alcohol in the bloodstream?

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    Answer B: Time

    The liver removes alcohol at a fixed rate, so nothing but the passage of time reduces blood alcohol concentration.

  30. 30. An enforcement officer inspects your vehicle at the roadside and attaches an out-of-service sticker. What may you do?

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    Answer C: Nothing until the defect is repaired; the vehicle may not be driven

    An out-of-service order means the vehicle is unsafe, and no schedule, load or destination allows it to be driven before the defect is corrected.

  31. 31. Under Wisconsin's commercial license rules, what makes a combination of vehicles a Class A rig?

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    Answer B: A combined weight over 26,000 pounds where the towed unit alone is rated over 10,000 pounds

    Wisconsin defines Class A as any combination over 26,000 pounds GVWR, actual, or registered weight, where the towed vehicle alone is rated over 10,000 pounds.

  32. 32. 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.

  33. 33. You are inspecting the vehicle alone and need to confirm that the stop lights work. Which method is correct?

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    Answer A: Have a helper press the brake pedal, or apply the brake in a way that keeps it on while you check from outside

    Stop lights are checked from outside the vehicle while the brakes are applied, so a helper or a brake held on is needed.

  34. 34. You want to check whether a tire on your truck is properly inflated. What is the correct method?

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    Answer A: Measure the pressure with a tire gauge

    Only a tire gauge tells you the actual pressure; a tire can look and sound normal while being badly underinflated.

  35. 35. Why should a driver avoid stopping partway up a snow covered hill?

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    Answer D: You may not get moving again and could slide backwards

    On a slippery grade the drive wheels may simply spin when you try to restart, leaving the vehicle stuck across the road or sliding back down it.

  36. 36. What is the risk when too little weight rests on the drive axles?

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    Answer A: Poor traction, so the drive wheels spin easily on wet or slippery surfaces

    Traction depends on weight pressing the driving tires onto the road, so a light drive axle spins on wet, snowy or loose surfaces.

  37. 37. A driver behind you wants to pass and you can see that the road ahead is clear. What should you do?

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    Answer B: Do not signal the other driver to pass; let that driver decide when it is safe

    Directing other drivers can cause a crash if you misjudge the gap, so leave the decision to the driver who is passing.

  38. 38. Dry bulk tanks call for extra caution mainly because of what?

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    Answer C: A high center of gravity combined with a load that can shift

    Dry bulk loads ride high and can move inside the tank, which makes the vehicle easier to tip in a curve.

  39. 39. You hear air escaping from a trailer tire during the pre-trip. What should you do?

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    Answer C: Have it repaired or replaced before the vehicle is driven

    An audible leak means the tire is failing now, and federal rules do not allow a vehicle to be operated on a flat or leaking tire.

  40. 40. 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.

  41. 41. An article of cargo has been blocked so that it cannot move forward. How many tiedowns does the federal rule call for?

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    Answer A: One tiedown for every 10 feet of article length, or any part of that

    Blocking against forward movement lowers the requirement to one tiedown per 10 feet of length or fraction of 10 feet.

  42. 42. 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.

  43. 43. How does the working load limit of a tiedown relate to the force that would break it?

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    Answer B: The working load limit is a fraction of the breaking strength and is the figure you use

    The working load limit is set well below the point at which the device would fail, and securement is always calculated from the working load limit, never from breaking strength.

  44. 44. What must a written driver vehicle inspection report cover at the end of the day?

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    Answer C: Any defect or deficiency that would affect safety or could cause a mechanical breakdown

    The report identifies the vehicle and lists defects that affect safe operation or could lead to a breakdown, so they are repaired before the next trip.

  45. 45. Why is cargo often covered with a tarp?

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    Answer C: To protect people from spilled cargo and to protect the cargo from weather

    A cover keeps material from blowing or spilling onto the road and shields the load from rain and sun; it does not replace securement.

  46. 46. 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.

  47. 47. After passing the Wisconsin hazardous materials knowledge test, how soon must an applicant complete TSA fingerprinting?

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    Answer D: Within 7 days

    Wisconsin requires an H endorsement applicant to complete fingerprinting at an approved location within 7 days of passing the knowledge test.

  48. 48. How should a driver use brakes fitted with an antilock system during an emergency stop?

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    Answer C: Brake as usual and keep enough pressure to stay in control while steering around the hazard

    The system only works when the brakes are applied hard enough for it to act, so the driver keeps pressure on and steers while the system prevents lockup.

  49. 49. You are unsure whether your vehicle will fit through a narrow gate. What should you do?

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    Answer A: Stop, get out and look, and take another route if the space is not clearly enough

    Clearance is never guessed at from the seat; you look at it on foot and go round rather than trying a gap that may be too tight.

  50. 50. Which windshield condition should be reported during the inspection?

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    Answer B: Cracks or dirt that get in the way of your view of the road

    The windshield must give a clear view; damage or grime in the driver line of sight is a safety defect.