New Mexico MVD CDL General Knowledge Practice Test 9

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

Minimum age: 18 years, with a K restriction limiting drivers to intrastate commerce where it applies

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

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

    Show answer

    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.

  2. 2. Why must the driver of a large vehicle keep it centered in its lane?

    Show answer

    Answer B: The vehicle needs the full width of the lane

    A commercial vehicle is close to lane width already, so any drift takes part of the vehicle into the next lane or onto the shoulder.

  3. 3. A fire has started in the vehicle. How should the extinguisher be used?

    Show answer

    Answer B: Stay as far back as the reach of the extinguisher allows, stand upwind, and aim at the base of the fire

    Aiming at the base attacks what is actually burning, and staying upwind and well back protects the driver from heat, smoke and the flames themselves.

  4. 4. How often must every commercial motor vehicle receive a periodic inspection?

    Show answer

    Answer C: At least once every twelve months

    Federal rules require each commercial motor vehicle to pass a periodic inspection at least once in every twelve month period.

  5. 5. 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.

  6. 6. A company mechanic serviced your truck this morning and signed the work order. Do you still have to inspect the vehicle?

    Show answer

    Answer B: Yes, the driver is still responsible for being satisfied the vehicle is safe

    Shop work does not transfer the duty; the driver who takes the vehicle out remains responsible for being satisfied it is in safe operating condition.

  7. 7. You are pulling away from the curb after a delivery. Why is a mirror check needed first?

    Show answer

    Answer B: A cyclist or a vehicle may be coming up alongside you

    Traffic and cyclists can arrive alongside a parked vehicle at any moment, so the mirrors must be checked immediately before pulling out.

  8. 8. 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.

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

    Show answer

    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.

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

    Show answer

    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.

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

    Show answer

    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.

  12. 12. 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.

  13. 13. What must a New Mexico applicant do to get a new commercial driver's license if their old CDL has been expired for more than five years?

    Show answer

    Answer B: Retake the CDL skills test

    New Mexico requires an applicant whose CDL has been expired for more than five years to retake the skills test before a new commercial license can be issued.

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

    Show answer

    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.

  15. 15. Federal rules forbid operating a commercial vehicle in which condition?

    Show answer

    Answer C: In a condition likely to cause a crash or a breakdown

    A defect that makes a crash or a breakdown likely has to be corrected before the vehicle is driven, not reported at the end of the trip.

  16. 16. What does the driver check in the final step of the seven-step inspection?

    Show answer

    Answer A: Hydraulic brake leaks where those brakes are fitted, then the parking brake and the service brakes

    The last step is done with the engine started: test for hydraulic leaks on vehicles with hydraulic brakes, then prove that the parking brake holds and that the service brakes stop the vehicle.

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

    Show answer

    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.

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

    Show answer

    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.

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

    Show answer

    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.

  20. 20. What is generally the safest speed in dense but freely moving highway traffic?

    Show answer

    Answer D: The speed of the traffic around you, up to the posted limit

    Crashes rise with the difference between your speed and the traffic around you, so moving with the flow within the legal limit is safest.

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

    Show answer

    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.

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

    Show answer

    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.

  23. 23. What credential must a New Mexico applicant hold before receiving a New Mexico commercial driver license?

    Show answer

    Answer D: A non-commercial Class D New Mexico license or a valid out-of-state commercial license

    New Mexico requires either a regular Class D license from the state or a valid commercial license from another jurisdiction before a New Mexico commercial license is issued.

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

    Show answer

    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.

  25. 25. What information does an inspection decal on a commercial vehicle carry?

    Show answer

    Answer B: The date of the inspection, where the inspection report is kept, and information identifying the vehicle

    The decal shows when the inspection was done, the name and address of the entity that holds the inspection report, and which vehicle it belongs to, so an officer can confirm the inspection at a glance.

  26. 26. 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?

    Show answer

    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.

  27. 27. Where on the road are you most likely to find ice in cold weather?

    Show answer

    Answer B: On bridges, overpasses and shaded stretches, which freeze before the rest of the road

    Bridges and overpasses lose heat from above and below, and shaded areas get no sun, so they ice over first and stay icy longest.

  28. 28. A commercial vehicle stops on the shoulder of an undivided two-lane road that carries traffic in both directions. Where do the warning devices go?

    Show answer

    Answer B: Within 10 feet of the vehicle, plus 100 feet to the front and 100 feet to the rear

    On a two-way road the devices must mark the vehicle itself and warn traffic approaching from each direction, and they must be in place within ten minutes.

  29. 29. Why is driving much slower than the rest of the traffic dangerous?

    Show answer

    Answer B: Other drivers must keep passing you, which creates conflicts

    Traffic that has to work its way around you produces lane changes and closing speeds, which is why a large speed difference is itself a hazard.

  30. 30. Besides staying secure, cargo carried inside a vehicle must not do what?

    Show answer

    Answer C: Block the driver view or access to emergency equipment and exits

    Cargo may not obstruct the view to the front or sides or prevent the driver from reaching emergency equipment and exits.

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

    Show answer

    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.

  32. 32. A commercial driver is convicted of two serious traffic violations within three years. What is the result?

    Show answer

    Answer D: Disqualification for 60 days

    Two serious traffic violations in a three year period bring a 60 day disqualification, and a third in the same period raises it to 120 days.

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

    Show answer

    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.

  34. 34. You are driving past a park where children are playing close to the curb. What is the correct assumption?

    Show answer

    Answer A: A child may run into the street without looking

    Children act on impulse and do not judge traffic well, so a driver has to expect one to enter the road and slow down in advance.

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

    Show answer

    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.

  36. 36. You have stopped and a pedestrian is waiting to cross in front of your truck. Why should you not wave the person across?

    Show answer

    Answer C: Another driver may not stop, and your wave sends the person into danger

    You cannot control what drivers in the other lanes will do, so you should not invite a pedestrian into a lane you do not command.

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

    Show answer

    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.

  38. 38. An unblocked article is 8 feet long and weighs 900 pounds. How many tiedowns does the federal rule require?

    Show answer

    Answer B: Two

    Only an article that is 5 feet or shorter and 1,100 pounds or lighter can be held with a single tiedown; anything longer than 5 feet needs at least two whatever it weighs.

  39. 39. A brake light lens is cracked and the lamp still lights. How should that be treated?

    Show answer

    Answer B: As a defect, because water can enter and the lamp can dim or fail

    A cracked lens lets in water and dirt, which corrodes the socket and dulls the lamp, so it is reported before it becomes a dead brake light.

  40. 40. What do the U-bolts on a leaf spring suspension do?

    Show answer

    Answer A: They clamp the spring assembly to the axle so it cannot move

    U-bolts hold the spring pack tight against the axle, and a loose or broken U-bolt lets the axle slide out of place under load.

  41. 41. 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.

  42. 42. You are moving an oversized load under a permit that requires a pilot vehicle. What is the pilot vehicle there to do?

    Show answer

    Answer B: Warn other traffic and check the route ahead for clearances and hazards

    Escort or pilot vehicles warn approaching traffic and scout the route for low bridges, narrow spots and other hazards that a wide or long load cannot pass.

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

    Show answer

    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.

  44. 44. How do you avoid the sharp lurch that comes at the very end of a stop in a heavy vehicle?

    Show answer

    Answer A: Ease off the brake pressure just before the vehicle actually comes to rest

    A smooth stop is finished by reducing pedal pressure as the vehicle settles, so the suspension does not rock the cab and the load forward.

  45. 45. What is the driver responsible for when a load is covered with a tarp?

    Show answer

    Answer C: Fastening it so it cannot flap free, block a mirror, or come off in the wind

    A tarp that works loose can tear away, block the driver view or the view of others, and become a hazard for the traffic behind.

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

    Show answer

    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.

  47. 47. How are the extra gears of a multi-speed rear axle or auxiliary transmission usually controlled?

    Show answer

    Answer D: With a selector knob or switch on the gearshift lever of the main transmission

    A range selector on the shift lever lets the driver choose the extra gear range while shifting the main transmission.

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

    Show answer

    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.

  49. 49. A dispatcher tells you to take a trailer you believe is loaded badly enough to be unsafe. What should you do?

    Show answer

    Answer C: Refuse to move it until the load has been made safe

    The driver may not operate a vehicle whose cargo is not properly distributed and secured, and an instruction from an employer does not change that.

  50. 50. A roadside test shows a commercial driver has measurable alcohol in the system but below 0.04. What happens?

    Show answer

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

    Any measurable alcohol while on duty results in an immediate 24 hour out of service order, even when the concentration is under the 0.04 limit.