Wisconsin WisDOT DMV CDL General Knowledge Practice Test 9

  • 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. What does the gross combination weight rating cover?

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    Answer B: The maximum loaded weight of the power unit together with the trailer or trailers it tows

    The combination rating takes in the power unit and everything behind it, loaded, as specified by the manufacturer.

  2. 2. How many questions are on the Wisconsin general knowledge test for a Class B or Class C commercial license?

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    Answer D: 50 questions

    Wisconsin uses a 50 question general knowledge test covering sections 1 to 3 of the Commercial Driver's Manual for Classes B and C.

  3. 3. At 55 mph on dry pavement with good brakes, total stopping distance for a loaded heavy vehicle is roughly what?

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    Answer B: About 400 feet or more

    Perception, reaction, and braking together add up to roughly 400 feet or more, farther than the length of a football field.

  4. 4. An angry driver has cut in front of you and is now braking hard to provoke you. What is the safest response?

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    Answer D: Drop back, avoid eye contact and let the driver go

    Giving an aggressive driver space and no response removes the conflict, while any answering gesture invites escalation you cannot control in a heavy vehicle.

  5. 5. What does the working load limit stamped on a chain or strap describe?

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    Answer B: The maximum load the device is rated to hold in normal use

    The working load limit is the rated safe capacity for everyday use, deliberately set well below the force that would break the device.

  6. 6. Some commodities have their own detailed securement rules on top of the general ones. Which list is made up of such commodities?

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    Answer C: Logs, metal coils, paper rolls, concrete pipe and crushed vehicles

    The cargo securement rules add specific requirements for particular commodities, including logs, dressed lumber, metal coils, paper rolls, concrete pipe, intermodal containers, vehicles, crushed cars, roll on containers and large boulders.

  7. 7. What financial benefit does a current or recent service member get when applying for a Wisconsin CDL with a valid military commercial license?

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    Answer B: All CDL issuance and renewal fees are waived

    Wisconsin waives all CDL issuance and renewal fees for an applicant who presents a valid military CDL.

  8. 8. In a vehicle with a manual transmission, when should the clutch be pushed in during a normal stop?

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    Answer A: Just before the engine would stall, when the vehicle is nearly stopped

    Staying in gear until the last moment keeps engine braking and steady control, so the clutch goes down only when the engine is about to drop below idle.

  9. 9. What is axle weight?

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    Answer C: The weight carried to the ground by one axle or one set of axles

    Axle weight describes how the load is shared among the axles that carry it to the road, not how much the whole vehicle weighs.

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

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    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.

  11. 11. 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.

  12. 12. 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.

  13. 13. Regular mirror checks during a long trip can reveal which developing problem?

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    Answer D: Smoke coming from a tire or from a wheel

    Overheating tires, wheel bearings and brakes usually show as smoke long before anything appears on the dash, and mirrors are where a driver sees it.

  14. 14. Cargo falls from your trailer and causes a crash behind you. Who is likely to answer for it?

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    Answer C: The driver and the carrier, since securing the load on the road is their duty

    Whoever loaded the vehicle, the driver and the carrier are responsible for the load being secure while it is on the road.

  15. 15. What does an N endorsement authorize a Wisconsin commercial driver to operate?

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    Answer C: Tank vehicles

    Wisconsin's N endorsement authorizes a commercial driver to operate tank vehicles.

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

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    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.

  17. 17. 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.

  18. 18. 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.

  19. 19. Which winter preparation matters most for keeping the road in view?

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    Answer D: Working wipers, washer fluid and a working defroster

    Slush and road spray coat the windshield within minutes in winter, so wipers, washer fluid and the defroster are what keep any view at all.

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

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    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.

  21. 21. You must leave the vehicle parked on a slight grade. What adds security beyond setting the parking brake?

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    Answer D: Chocking the wheels so the vehicle cannot roll if the brake bleeds off

    Chocks hold the vehicle mechanically and are the standard backup whenever a parked vehicle could roll.

  22. 22. An oncoming vehicle drifts across the center line into your lane. What is usually the safest move?

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    Answer C: Steer to the right, toward the shoulder if necessary

    Moving right keeps you away from the drifting vehicle and off the oncoming side; the other driver may swerve back and hit you if you go left.

  23. 23. 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.

  24. 24. The engine has overheated and you need to check the coolant. What is the safe procedure with a pressurized radiator cap?

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    Answer A: Shut the engine off, let the system cool, protect your hands, turn the cap slowly to its first stop so pressure escapes, step back, then remove it

    A hot pressurized system throws steam and boiling coolant out of the opening, so the pressure is released slowly and only after the engine has cooled.

  25. 25. May a commercial driver use a hand-held phone while stopped at a red light?

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    Answer B: No, a stop in traffic still counts as driving

    Hand-held use is allowed only when the vehicle has been moved to the side of or off the highway and halted where it can safely remain stopped.

  26. 26. Below 40 mph, what following distance does the standard commercial rule of thumb call for?

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    Answer C: One second for every 10 feet of vehicle length

    The base rule allows one second of space for each 10 feet of vehicle length while speed stays under 40 mph.

  27. 27. What is the coupling device weight rating on a vehicle?

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    Answer A: The most weight that the coupling on the vehicle is rated to pull

    The coupling device rating is a limit on how much weight the coupling may tow, and it is one of the ratings that has to be respected when a combination is loaded.

  28. 28. During the engine compartment check, which leaks are you looking for?

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    Answer D: Fuel, coolant, engine oil, power steering fluid and battery fluid

    Every fluid in the compartment matters, because a fuel leak is a fire risk and a loss of coolant, oil, steering fluid or electrolyte can disable the vehicle.

  29. 29. 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.

  30. 30. An unblocked crate 4 feet long and weighing 900 pounds needs at least how many tiedowns?

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    Answer D: One

    An article 5 feet or less in length and 1,100 pounds or less in weight is covered by a minimum of one tiedown.

  31. 31. Which description matches controlled braking during an emergency stop?

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    Answer D: Apply the brakes as hard as you can without locking the wheels and keep steering movements small

    Controlled braking keeps the wheels rolling just short of lockup, which gives the shortest stop while you keep the ability to steer.

  32. 32. What does the F endorsement mean on a Wisconsin commercial driver license?

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    Answer C: Farm service, restricted to farm service operation

    Wisconsin uses the F endorsement for a restricted farm service CDL available to people employed by a farm service industry for 210 days or less per calendar year.

  33. 33. Why does a load of live animals need special attention?

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    Answer D: The animals move and lean, so the center of gravity shifts and the vehicle can be pushed off balance in a turn

    A live load will not stay where it is put, and that movement changes the balance of the vehicle exactly when a curve is loading it most.

  34. 34. Why are the windshield wipers on the pre-trip list even before a trip in fine weather?

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    Answer C: Because weather can change and a wiper failure leaves the driver without a clear view

    Rain, spray or mud can arrive at any point in a long trip, and a wiper that fails then leaves the driver with no way to clear the windshield.

  35. 35. A load overhangs the rear of the trailer. What must the driver check before leaving?

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    Answer D: That the overhang is marked as required, with flags or lamps as conditions demand

    A projecting load has to be made visible to other drivers, with flags in daylight and lamps when lights are required, so nobody runs into what they cannot see.

  36. 36. During the walkaround inspection, where does the driver normally start and how does the check proceed?

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    Answer C: At the left front of the vehicle, working around it in a set order that returns to the cab

    The walkaround follows the same route every time, starting at the left front and circling the vehicle, so that nothing is skipped when the driver is tired or rushed.

  37. 37. What do you check about the fire extinguisher during the pre-trip?

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    Answer C: That it is securely mounted, charged and that you know how to operate it

    An extinguisher must be held in its bracket, show a charged gauge and be understood by the driver, because a fire leaves no time to learn.

  38. 38. Why should a driver avoid traveling alongside another vehicle for any length of time?

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    Answer D: You lose your escape route and you may be sitting in the other driver blind spot

    Running beside someone leaves nowhere to move if you have to change lanes, and the other driver may not know you are there at all.

  39. 39. A 40 foot straight truck and a 70 foot tractor-trailer make the same right turn. Which needs more room and why?

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    Answer B: The tractor-trailer, because the longer the vehicle the farther inside the rear wheels track

    Off-tracking grows with the distance between the front and rear axles, so the longer combination cuts the corner much more sharply and needs extra room.

  40. 40. What should you look for on the electrical wiring in the engine compartment?

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    Answer A: Worn, frayed or cracked insulation and loose or corroded connections

    Damaged insulation can short a circuit against the frame or engine, which can kill a lamp you depend on or start a fire.

  41. 41. A driver snores heavily, stops breathing briefly during the night and is tired all day despite long hours in bed. What should be suspected?

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    Answer B: Sleep apnea

    Sleep apnea repeatedly interrupts breathing during sleep, so the driver never gets true rest and stays dangerously drowsy during the day.

  42. 42. 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.

  43. 43. What tells a driver when to shift up in a vehicle with a manual transmission?

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    Answer C: Engine speed in rpm together with road speed

    Shift points are judged from engine rpm and road speed, using the operating range the manufacturer specifies for that engine.

  44. 44. What does the commercial driver manual tell you to do with the parking brake when you leave your vehicle?

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    Answer B: Apply the parking brake every time you leave the vehicle

    The manual is explicit that the parking brake goes on whenever the driver leaves the vehicle, because once nobody is at the controls it is the only thing holding it.

  45. 45. Taking your eyes off the road for about five seconds at highway speed means traveling roughly how far unseen?

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    Answer A: About the length of a football field

    At highway speed a five second glance away covers roughly 100 yards, which is far more road than any driver can afford to travel blind.

  46. 46. You stop to check the load. Which set of things are you looking at?

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    Answer C: Tight tiedowns, cargo that has not moved, secure doors and tarps still fastened

    A cargo check covers the load and everything holding it: whether it has shifted, whether the devices are still tight, and whether doors and covers are still closed and fastened.

  47. 47. Where on a tire is tread depth measured?

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    Answer C: In a major tread groove, away from any tie bar or wear indicator

    Depth is taken in a major groove and away from the raised tie bars and wear indicators, which would give a shallower and misleading reading.

  48. 48. Which vehicle is most likely to be pushed around by a strong crosswind?

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    Answer B: An empty van trailer

    A large flat side with very little weight behind it gives the wind the most surface and the least resistance, which is the empty van trailer.

  49. 49. The engine oil pressure gauge falls toward zero while you are driving. What should you do?

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    Answer C: Stop as soon as it is safe to do so and shut the engine down

    Loss of oil pressure destroys an engine in a very short time, so the correct response is to stop and shut down rather than to drive on.

  50. 50. Which parts of total stopping distance can a driver shorten simply by staying alert and looking far ahead?

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    Answer B: Perception distance and reaction distance

    Alertness shortens the time spent recognizing a hazard and moving your foot to the pedal; braking distance depends on speed, weight, brakes and the road surface.