Kentucky KYTC 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 Kentucky test.

A road through bluegrass pastures with horse fences, a typical landscape of Kentucky

Minimum age: 18 years for intrastate driving with a K restriction, 21 years without it

  1. 1. Why does a load of hanging meat in a refrigerated trailer require special care in curves?

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    Answer D: The meat swings and has a high center of gravity, which makes the trailer unstable

    Hanging meat is heavy, sits high and swings, so the trailer can tip in a curve or on a ramp taken at normal speed.

  2. 2. What should be done before a night trip to get the most from your headlights?

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    Answer C: Clean the windshield, the mirrors and the lights

    Dirt on glass and lenses cuts both the light you throw down the road and the light that reaches your eyes, so cleaning is the cheapest night safety measure there is.

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

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    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.

  4. 4. Which road users are hardest to see at night?

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    Answer C: Pedestrians and cyclists in dark clothing

    People on foot or on a bicycle carry no lights of their own in many cases, so they appear only when the headlights reach them.

  5. 5. At the scale your tractor drive axles are overweight while the trailer axles have room. Sliding the trailer tandems forward will do what?

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    Answer C: Move weight off the drive axles and onto the trailer axles

    Sliding the trailer tandems forward brings the rear support closer to the load, so the trailer axles pick up more weight and the drive axles carry less; sliding them rearward does the opposite.

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

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    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.

  7. 7. A straight truck has a long body behind the rear axle. What happens to that overhang in a sharp left turn?

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    Answer D: It swings out to the right and can strike a vehicle or an object on that side

    Body that hangs behind the rear axle swings the opposite way to the turn, so the tail of the truck sweeps out into the next lane or over the curb.

  8. 8. Within total stopping distance, what exactly is perception distance?

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    Answer D: The distance traveled from the moment your eyes see a hazard until your brain identifies it

    Perception distance covers only the time between seeing a hazard and recognizing it as a hazard, before any physical reaction begins.

  9. 9. Why should both outside mirrors be checked over and over while backing?

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    Answer B: Each mirror covers only part of the path and neither covers the blind spots, so people and objects can appear without warning

    Working both mirrors in turn is the only way to follow the whole path of a vehicle you cannot see behind.

  10. 10. A driver hauling a sealed trailer that cannot be opened is still responsible for what?

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    Answer D: Making sure the rig is not over the gross or axle weight limits

    A seal prevents inspecting the contents, but the driver must still confirm the vehicle is not overloaded.

  11. 11. 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.

  12. 12. 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.

  13. 13. 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.

  14. 14. 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.

  15. 15. What does the K restriction on a Kentucky commercial driver's license mean?

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    Answer A: The driver is limited to Kentucky intrastate commerce

    The Kentucky CDL Manual states that a CDL issued to an individual between 18 and 20 years of age is class specific and carries a K restriction noting that the commercial driver is limited to Kentucky intrastate commerce.

  16. 16. 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.

  17. 17. Why does a driver use pull-ups while backing into a tight space?

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    Answer C: To pull forward and start the approach again when the angle is going wrong

    Stopping, pulling ahead and repositioning fixes a bad angle safely, and there is nothing wrong with needing more than one attempt.

  18. 18. 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.

  19. 19. 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.

  20. 20. What is checked in step six of the seven-step method?

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    Answer D: The turn signals and the stop lights, checked from outside the vehicle

    Step six returns to the cab to switch on the signal and stop lamps, then checks each one from outside, because those lamps are not lit during the earlier light check.

  21. 21. How should speed and gears be handled when approaching a curve?

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    Answer A: Slow to a safe speed and downshift before entering the curve

    Braking and shifting are completed before the curve so the vehicle is settled and can pull gently through it without upsetting the load.

  22. 22. What is normally required in order to move an over-width or over-length load?

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    Answer B: A special permit along with warning devices such as flags and signs

    Oversize movements need a permit plus marking devices, and travel is often limited to certain hours or routes.

  23. 23. Why must a bent, cracked or badly seated lock ring be reported?

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    Answer D: It can come off under pressure and let the tire and rim separate violently

    The lock ring holds the assembly together against the full pressure of the tire, so a damaged ring can release with enough force to kill.

  24. 24. What does the tachometer on the dashboard of a heavy truck show?

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    Answer D: How fast the engine is turning, in revolutions per minute

    The tachometer reads engine speed in rpm, which is what a driver uses to judge shift points in a vehicle with a manual transmission.

  25. 25. What does mountain driving demand that flat country driving does not?

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    Answer D: Lower gears and constant allowance for gravity

    In the mountains gravity works for you on the climb and against you on the descent, so gear selection and speed control matter far more than on level road.

  26. 26. 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.

  27. 27. What makes a brake hose or air line a defect during the walkaround?

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    Answer D: It is cracked, worn, kinked, or rubbing against another part

    A chafed or cracked line can burst under pressure and take the braking on that circuit with it, so damage and rubbing points must be corrected.

  28. 28. Before raising the hood to inspect the engine compartment, what should you do?

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    Answer B: Shut off the engine, set the parking brake and chock the wheels if needed

    The engine compartment is inspected with the engine off and the vehicle secured so nothing can move or turn while your hands are inside.

  29. 29. 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.

  30. 30. Around a tractor-trailer, where are the blind areas that other drivers most often sit in unseen?

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    Answer A: Along the right side and directly behind the trailer

    The blind areas to the right of the cab and behind the trailer are the largest, which is why other drivers should never linger there.

  31. 31. 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.

  32. 32. A tire blows out at highway speed. What should the driver do first?

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    Answer C: Hold the steering wheel firmly, stay off the brake and let the vehicle slow down

    Braking while a tire is gone can pull the vehicle out of line, so the driver keeps it straight and lets speed fall before easing off the road.

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

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    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.

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

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    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.

  35. 35. What is the correct order for a double clutch downshift?

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    Answer D: Release the accelerator and push the clutch to reach neutral, release the clutch and press the accelerator to raise engine speed, then push the clutch again and select the lower gear

    A lower gear turns faster than the one being left, so engine speed has to be raised in neutral before that gear will engage cleanly.

  36. 36. You are taking a tightly curved highway exit ramp in a long combination. Where should the tractor be placed within the lane?

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    Answer D: Toward the outside of the curve, leaving room for the trailer to track inside

    Because the trailer wheels cut to the inside of the curve, the tractor has to be kept out toward the outer edge so the trailer does not drop a wheel off the inside edge.

  37. 37. A tire may be regrooved only when what is true?

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    Answer B: It carries a marking from the manufacturer showing that it is regroovable

    Only casings built with extra rubber under the tread and marked regroovable by the manufacturer may be cut, because others would be grooved into the belts.

  38. 38. What should a driver assume about the height posted at a bridge or an overpass?

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    Answer B: That it may be wrong, because repaving or packed snow can leave less clearance than the sign shows

    Resurfacing and packed snow raise the road under the structure, so the real clearance can be lower than the posted figure.

  39. 39. Why must tiedowns be rechecked during a trip even when they were tight at the start?

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    Answer C: Road vibration and cargo movement can loosen them as the miles go by

    Straps and chains settle and loosen as the vehicle bounces and the cargo shifts slightly, so the load must be rechecked at the required intervals.

  40. 40. 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.

  41. 41. How long is a Kentucky CDL instruction permit valid, and how long must it be held before the skills test?

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    Answer B: Valid six months, held 14 days

    The Kentucky CDL Manual states that the CDL instruction permit is valid for six months and must be held for 14 days before a skills test is administered.

  42. 42. In dense city traffic you cannot see 12 seconds ahead because other vehicles block the view. What is the best response?

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    Answer A: Slow down and open up more space in front of you

    When you cannot see far enough ahead, extra following distance buys back the reaction time that the blocked view has taken away.

  43. 43. How does a front tire failure usually feel to the driver?

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    Answer D: The steering suddenly becomes heavy and pulls to one side

    A failed front tire loads the steering and makes the wheel feel heavy, while a rear tire failure shows up as the back end swaying.

  44. 44. Apart from the risk of stalling, why is rolling backwards when starting on an upgrade so serious in a heavy vehicle?

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    Answer D: You can strike the vehicle behind you, which is often much closer than you think

    You cannot see how close the vehicle behind has stopped, and even a short roll back is enough to hit it.

  45. 45. What should be checked about the power steering system in the engine compartment?

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    Answer D: That the fluid level is correct and the hoses and pump are not leaking

    Losing power steering fluid means losing steering assistance, which can happen suddenly and makes a heavy vehicle very hard to turn.

  46. 46. What should you check about the air hoses and the electrical cord running to the trailer?

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    Answer D: That they are free of damage, properly connected and not dragging or rubbing

    Lines that chafe on the frame or drag on the road wear through, and a broken line takes away trailer braking or trailer lighting without warning.

  47. 47. Why should a driver avoid shifting gears in the middle of a turn at an intersection?

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    Answer D: Shifting during the turn takes a hand off the wheel and can cost you control

    Pick the gear before you begin turning; shifting in the turn removes a hand from the wheel and can interrupt power just when you need steady control.

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

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    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.

  49. 49. 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.

  50. 50. 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.