Michigan SOS CDL General Knowledge Practice Test 8

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

    Show answer

    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.

  2. 2. After coupling, where should the fifth wheel release handle be?

    Show answer

    Answer A: In the locked position with the safety latch in place

    The handle must be pushed in and latched, because a handle left out means the jaws can open and release the trailer while you are driving.

  3. 3. How is the fluid level in an automatic transmission usually checked?

    Show answer

    Answer A: With the engine running, following the procedure in the operator manual

    Most automatic transmissions are designed to be checked with the engine running, and the operator manual gives the exact conditions for that vehicle.

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

    Show answer

    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.

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

    Show answer

    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.

  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. 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.

  8. 8. You drive a 40 foot straight truck at 50 miles per hour in good conditions. What following distance does the rule of thumb call for?

    Show answer

    Answer A: 5 seconds

    One second for every 10 feet of vehicle length gives 4 seconds, and one extra second is added for speeds above 40 miles per hour.

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

    Show answer

    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.

  10. 10. During the walkaround you find the reflective conspicuity tape along the trailer caked with road grime. What should you do?

    Show answer

    Answer B: Clean it, because dirty reflective material cannot make the trailer visible at night

    Reflective sheeting only works if light can reach it and bounce back, so a dirty strip leaves the trailer effectively unmarked to approaching traffic.

  11. 11. When should a driver add space beyond the basic following distance rule?

    Show answer

    Answer D: On slippery roads and whenever visibility is poor

    The seconds rule is a minimum for good conditions, so rain, snow, darkness and heavy traffic all call for more space than that.

  12. 12. 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.

  13. 13. Your brakes are starting to fade on a mountain downgrade and a sign shows an escape ramp one mile ahead. What should you do?

    Show answer

    Answer B: Plan to use the ramp instead of trying to reach the bottom

    Fading brakes on a grade only get worse, and the ramp exists precisely so a driver does not have to gamble on the rest of the descent.

  14. 14. During a trip you stop for a break. Which items should you check before driving on?

    Show answer

    Answer B: Tires, wheels and rims, brakes, lights, reflectors, electrical connections and cargo securement

    Critical items can change during a trip, so each stop is used to recheck the tires, wheels, brakes, lights, connections and cargo.

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

    Show answer

    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.

  16. 16. Federal rules keep recapped and retreaded tires off the front wheels of which vehicle?

    Show answer

    Answer B: Any bus carrying passengers

    The federal rule names buses: a bus may not run with regrooved, recapped or retreaded tires on its front wheels, because a steer tire failure with passengers aboard takes away steering control.

  17. 17. You have countersteered to correct a rear-wheel skid and the vehicle straightens out. What must you be ready for next?

    Show answer

    Answer D: The vehicle may swing back the other way, so you must steer again to correct it

    A vehicle coming out of a skid tends to overshoot and swing in the opposite direction, and the driver must be ready to countersteer a second time.

  18. 18. According to the Michigan Department of State, a commercial driver's license is required for a vehicle designed to transport how many people?

    Show answer

    Answer C: 16 or more, including the driver

    Michigan requires a CDL for a vehicle designed to transport 16 or more people, counting the driver.

  19. 19. During the walkaround you notice a bulge in the sidewall of a trailer tire. What does it indicate?

    Show answer

    Answer B: Damage inside the tire, which can lead to a sudden failure

    A bulge means the internal structure has broken and only the rubber is holding the air, so the tire can burst without warning.

  20. 20. What is required to obtain the Michigan F-endorsement used by farmers?

    Show answer

    Answer A: A knowledge test but no skills test

    The F-endorsement requires a knowledge test but no skills test, and it is not itself a commercial driver's license.

  21. 21. You are hauling a sealed trailer and have been told in writing not to open it. How does that affect the en route cargo checks?

    Show answer

    Answer C: You do not have to inspect the cargo itself, but the vehicle and weight are still yours

    The en route cargo inspection rule does not apply to a driver of a sealed vehicle who has been ordered not to open it, but every other responsibility, including legal weight, remains.

  22. 22. How do you confirm that the coupling is locked before pulling out of the yard?

    Show answer

    Answer D: By locking the trailer brakes and pulling gently forward against them

    The tug test loads the coupling in the direction that would pull it apart, so if the jaws are not closed on the kingpin you find out at walking pace.

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

    Show answer

    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.

  24. 24. You must steer hard around an obstacle at highway speed. What is the correct technique?

    Show answer

    Answer B: Avoid braking while turning, turn only as far as needed, and countersteer as soon as the obstacle is passed

    Braking during a hard steering input can lock the wheels and start a skid, and turning back at once keeps the vehicle from running off the far side of the road.

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

    Show answer

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

    Show answer

    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.

  27. 27. What are the rules for using your turn signal before a turn or lane change?

    Show answer

    Answer A: Signal early, keep the signal on until the turn is finished, then cancel it

    An early, continuous signal tells others what you plan to do; cancelling afterward keeps the signal from misleading them.

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

    Show answer

    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.

  29. 29. What is the minimum tread depth required in every major groove of a steering axle tire?

    Show answer

    Answer D: 4/32 inch

    Federal rules set a higher tread minimum for front steering tires than for other positions because a steering tire failure is far harder to control.

  30. 30. A fire starts in the cargo area of a van trailer. Why should you keep the doors closed until firefighters arrive?

    Show answer

    Answer D: Opening the doors lets in air that feeds the fire

    A fire in a closed van is starved of oxygen; opening the doors gives it the air it needs to flare up.

  31. 31. After starting the engine, how quickly should the oil pressure gauge come up to its normal range?

    Show answer

    Answer B: Within a few seconds

    Oil pressure should build within seconds of starting; if it stays low, the engine is not being lubricated and should be shut down.

  32. 32. An empty van trailer cleared a low overpass on the way in, but on the way back it is loaded. Which statement is true?

    Show answer

    Answer C: An empty van rides higher than a loaded one, so it needs more clearance than when loaded

    Springs compress under load, so an empty trailer is taller; the unloaded trip is the one that can catch a low overhead.

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

    Show answer

    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.

  34. 34. What blood alcohol concentration disqualifies the holder of a commercial driver license who is operating a commercial vehicle?

    Show answer

    Answer D: 0.04 or higher

    Commercial drivers are held to 0.04, half the limit that applies to a driver of a passenger car in the same state.

  35. 35. Who must sign a driver vehicle inspection report?

    Show answer

    Answer D: The driver who prepared it

    The report is the driver statement about the condition of the vehicle at the end of the day, so the driver signs it.

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

    Show answer

    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.

  37. 37. What must the motor carrier do about a defect listed on a driver vehicle inspection report?

    Show answer

    Answer D: Repair it, or certify that repair is not needed, before the vehicle is dispatched again

    A reported defect must be corrected, or certified as not needing correction, and that certification is what the next driver reads before taking the vehicle.

  38. 38. Your windshield washer reservoir is empty and rain and road spray are expected. What should you do?

    Show answer

    Answer D: Fill it before the trip, because you need the washers to keep the windshield clear

    Wipers alone smear the film of oil and grit thrown up by traffic, so the washers are part of keeping a usable view of the road.

  39. 39. After the first inspection of a trip, how often must cargo securement be checked again?

    Show answer

    Answer D: Every 3 hours or 150 miles or at each change of duty status, whichever happens first

    The load must be re-checked at whichever of those points arrives first, so a loosening tiedown is found long before it fails.

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

    Show answer

    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.

  41. 41. Who may remove an out-of-service sticker from a commercial vehicle?

    Show answer

    Answer B: Only an authorized person, and only after the defect that caused it has been repaired

    The sticker stays on the vehicle until the repairs are made and an authorized person removes it, so nobody can simply peel it off and drive away.

  42. 42. Why should you never back under a trailer whose landing gear is resting on soft or muddy ground?

    Show answer

    Answer C: The landing gear can sink or collapse and the trailer can drop or tip over

    Soft ground lets the landing gear sink under the load being transferred to it, and a trailer that drops or topples during coupling is extremely dangerous.

  43. 43. What is the first step of the standard seven-step vehicle inspection?

    Show answer

    Answer C: A general overview of the vehicle, including the last inspection report

    The routine opens with a walk-up overview of the vehicle and a review of the previous inspection report so known defects are addressed first.

  44. 44. At 55 mph, about how far does a vehicle travel during a typical 3/4 second perception time plus 3/4 second reaction time, before the brakes even begin to work?

    Show answer

    Answer C: About 120 feet

    Each 3/4 second at 55 mph covers about 60 feet, so perception and reaction together use up roughly 120 feet before braking starts.

  45. 45. 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.

  46. 46. You drop your phone on the floor of the cab while driving. What do federal rules require?

    Show answer

    Answer A: Leave it, because reaching for it while driving is banned

    Federal rules forbid reaching for a mobile device in any way that takes the driver out of a seated, belted driving position.

  47. 47. You are dropping a loaded trailer in a yard. How far should the landing gear be lowered?

    Show answer

    Answer A: Until the pads make firm contact and the trailer weight is just off the fifth wheel

    Cranking down until the gear is firmly on the ground and just lifting the load off the fifth wheel makes the trailer stable and lets the tractor pull out cleanly.

  48. 48. What is the penalty for a second Michigan hands-free violation in a commercial motor vehicle with no crash involved?

    Show answer

    Answer B: 500 dollars or 48 hours of community service

    A second or subsequent commercial hands-free violation that does not involve a crash carries a 500 dollar civil fine or 48 hours of community service, or both.

  49. 49. Which lamp must make the rear registration plate legible after dark?

    Show answer

    Answer C: A white lamp that lights the plate

    A white license plate lamp is required so the plate can be read at night, and a burned out one is a defect like any other lamp.

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

    Show answer

    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.