CCDL Permit Prep

General Knowledge · page 8 of 19

General Knowledge questions 141–160

Part of the 376-question General Knowledge pool. Each answer cites the FMCSA CDL Manual or the federal rule it comes from.

Practise these as a timed set

  1. Before driving under a bridge or into a building, you should be most concerned about:

    • ATire pressure
    • BFuel level remaining in the tank
    • CWhether your vehicle's height will clear the overhead spaceCorrect
    • DMirror position

    A loaded vehicle can change height, so confirm clearance before passing under bridges, signs, or doorways to avoid striking them.

    FMCSA Commercial Driver's License Manual · Section 2.9 - Managing Space - Overhead · verified 2026-09-08

  2. If you must stop on a one-way or divided highway, you should place the three warning triangles at:

    • A500 feet ahead only
    • B10, 100, and 200 feet toward approaching trafficCorrect
    • COnly directly behind the vehicle
    • D10, 100, and 200 feet behind, and one at the front bumper

    On a one-way or divided highway, place triangles at 10, 100, and 200 feet toward approaching traffic to warn drivers from the right direction.

    FMCSA Commercial Driver's License Manual · Section 2.2 - Communicating - Stopping On The Road · verified 2026-09-08

  3. When stopping for a railroad crossing in heavy traffic, you should:

    • AFollow closely behind the vehicle ahead onto the tracks
    • BStop with part of your vehicle on the tracks if needed
    • CMake sure you have room to completely clear the tracks before starting acrossCorrect
    • DStop on the tracks to check both directions

    Never start across tracks unless you can completely clear them, because stopping on the tracks in traffic can trap you in a train's path.

    FMCSA 2005 CDL Testing System Model Manual (July 2014) · Section 2.15 — Railroad-highway Crossings; Oregon Manual § 2.15.5 cross-check · verified 2026-09-19

  4. To avoid distracted driving in a CMV, you should:

    • AEat and review paperwork while driving to save time
    • BWatch videos during slow traffic
    • CUse a hand-held phone for short calls only
    • DSet up navigation and complete tasks before you start drivingCorrect

    Handling navigation, food, and paperwork before driving keeps your eyes and attention on the road where they belong.

    FMCSA Commercial Driver's License Manual · Section 2.17 - How To Avoid Distractions · verified 2026-09-08

  5. Your safe speed on a downgrade depends on the grade's steepness and length, the weather, and:

    • AThe total weight of the vehicle and cargoCorrect
    • BThe age of the tractor's engine
    • CThe time of day you are driving
    • DThe brand of brake linings fitted

    Heavier loads build more momentum downhill, so total weight, along with grade and road conditions, determines a safe descent speed.

    FMCSA Commercial Driver's License Manual · Section 2.7 - Speed On Downgrades · verified 2026-09-08

  6. To keep a space cushion to the sides, you should:

    • ADrive in the center of your lane, not alongside othersCorrect
    • BStraddle two lanes to claim extra space
    • CDrive in another vehicle's blind spot
    • DAlways hug the lane line

    Staying centered and not riding beside other vehicles keeps room to react if someone moves toward your lane.

    FMCSA Commercial Driver's License Manual · Section 2.9 - Managing Space - To The Sides · verified 2026-09-08

  7. Hydroplaning is more likely when:

    • ATires are worn or underinflated with standing waterCorrect
    • BTires are new and properly inflated
    • CDriving slowly on dry pavement
    • DThe load is evenly balanced

    Worn or underinflated tires cannot channel water away, so at higher speeds they ride up on standing water and lose grip.

    FMCSA Commercial Driver's License Manual · Section 2.6 - Standing Water And Hydroplaning · verified 2026-09-08

  8. Regular, brief glances at your mirrors while driving help you:

    • AFix your hair or check your appearance in the mirror
    • BIncrease your speed
    • CTrack traffic around you and spot problems with your tires or cargoCorrect
    • DAvoid looking ahead

    Frequent mirror checks let you monitor surrounding traffic and catch tire, cargo, or trailer problems before they become emergencies.

    FMCSA Commercial Driver's License Manual · Section 2.5 - Seeing - Use Of Mirrors · verified 2026-09-08

  9. An interstate CMV driver finishes a day with no defect found or reported. What does the federal DVIR rule require?

    • ANo DVIR is required solely to certify a no-defect dayCorrect
    • BA signed no-defect DVIR is required after every workday
    • CA DVIR is required only once each week
    • DA DVIR is replaced by the annual inspection report

    Federal rules do not require a driver to prepare a DVIR only to report that no defect was found or reported; since the 2026 amendment this applies to property- and passenger-carrying vehicles alike. A required report must identify defects or deficiencies that could affect safe operation or cause a breakdown. Other inspection duties and carrier or state procedures still apply.

    49 CFR § 396.11 · § 396.11(a)(2)(i)–(ii) — Report content and signature · verified 2026-09-23

  10. When checking the steering system during an inspection, you should look for:

    • AMissing nuts, bolts, or cotter keysCorrect
    • BProperly inflated spare tire
    • CClean windshield
    • DFuel level

    Loose or missing steering parts can cause loss of control, so inspect the steering box, linkage, and arms for wear and missing fasteners.

    FMCSA Commercial Driver's License Manual · Section 2.1.4 - Steering System Check · verified 2026-09-08

  11. During inspection, a missing or broken leaf in a leaf spring is:

    • AAcceptable if only one is cracked out of several leaves
    • BNormal wear that can be ignored
    • COnly a concern on trailers
    • DA dangerous defect; if one-fourth or more of the leaves are missing, the vehicle is out of serviceCorrect

    The FMCSA manual says any missing or broken leaf can be dangerous; one-fourth or more missing leaves place the vehicle out of service. Do not operate until the defect is addressed.

    FMCSA Commercial Driver's License Manual · Section 2.1.5 - Suspension System Check · verified 2026-09-08

  12. Which tire condition requires the tire to be taken out of service?

    • ASlightly dusty sidewall with no other damage
    • BRecently rotated tire
    • CA small stone in the tread
    • DFabric or body ply showing through the tread or sidewallCorrect

    Exposed fabric or body ply means the tire is badly worn or damaged and could fail, so it must be replaced before driving.

    FMCSA Commercial Driver's License Manual · Section 2.1.3 - Tires - Defects · verified 2026-09-08

  13. A leaking exhaust system on a CMV is dangerous because it can:

    • AMake the engine quieter
    • BImprove fuel economy
    • CLet poisonous carbon monoxide enter the cabCorrect
    • DIncrease tire pressure

    Exhaust leaks can send deadly carbon monoxide into the cab, so loose, broken, or leaking exhaust parts must be repaired before driving.

    FMCSA Commercial Driver's License Manual · Section 2.1.6 - Exhaust System Check · verified 2026-09-08

  14. Which statement accurately describes federally required emergency equipment for a commercial motor vehicle?

    • AA first-aid kit, blanket, and flashlight
    • BA jack, tow strap, and cones
    • CA properly rated fire extinguisher and compliant stopped-vehicle warning devicesCorrect
    • DSpare electrical fuses and flares, with no fire extinguisher required

    Federal rules require a properly rated, charged, accessible fire extinguisher and stopped-vehicle warning devices. Three reflective triangles are one allowed warning-device option; fusees are another option subject to hazardous-material restrictions. Spare fuses are no longer federally required.

    eCFR 49 CFR 393.95 — Emergency equipment on all power units · 393.95(a), (f), and (g); paragraph (b) reserved · verified 2026-09-07

  15. During inspection, brakes that are out of adjustment are dangerous because they:

    • AImprove fuel economy
    • BReduce braking force, lengthening stopping distanceCorrect
    • CMake the vehicle stop too quickly
    • DHave no effect on safety

    Out-of-adjustment brakes apply less force, so the vehicle needs a longer distance to stop, raising the risk of a crash.

    49 CFR § 393.47 · Brake adjustment · verified 2026-09-08

  16. During inspection, you should check wheels and rims for:

    • ACracks, damage, and missing or loose lug nutsCorrect
    • BCorrect tire pressure on each wheel
    • CHubcaps on every wheel
    • DMatching tread brands

    Cracked rims and missing or loose lug nuts can cause a wheel to come off, so inspect them carefully before every trip.

    FMCSA Commercial Driver's License Manual · Section 2.1.2 - Wheels And Rims · verified 2026-09-08

  17. If an inspection finds a defect likely to affect safe operation, the driver should:

    • ADrive carefully to the next town and fix it there
    • BNote it and continue the trip, without repairing a defect that may make operation illegal
    • CIgnore it if the trip is short
    • DHave the carrier repair it and certify the repair before operationCorrect

    Under 49 CFR 396.11, a defect likely to affect safe operation must be repaired or certified as unnecessary before the carrier permits the vehicle to operate. Not every minor issue is automatically an out-of-service defect.

    FMCSA Commercial Driver's License Manual · Section 11.5 - Out-Of-Service Defects · verified 2026-09-08

  18. The 14-hour rule means a property-carrying driver may not drive after:

    • A14 hours of driving
    • B14 days on the road
    • C14 hours off duty, regardless of when the shift began
    • DThe 14th hour after coming on duty, driving or notCorrect

    Once 14 hours have passed since coming on duty, driving must stop, even if breaks were taken, until another 10 hours off duty.

    49 CFR § 395.3 · 14-hour limit · verified 2026-09-08

  19. Under the 60/70-hour rule, a driver whose company operates every day of the week may not drive after being on duty:

    • A50 hours in 5 days
    • B40 hours in 7 days
    • C100 hours in 10 days
    • D70 hours in any 8 consecutive daysCorrect

    If the carrier runs every day, a driver may not drive after 70 hours on duty in any 8 consecutive days until hours rebuild.

    49 CFR § 395.3 · 60/70-hour limit · verified 2026-09-08

  20. A 34-hour restart allows a driver to:

    • ADrive an extra 4 hours that day
    • BSkip the required 30-minute break
    • CReset the 60- or 70-hour total to zeroCorrect
    • DExtend the 14-hour window

    Taking at least 34 consecutive hours off duty restarts the weekly 60- or 70-hour clock, letting the driver begin a fresh cycle.

    49 CFR § 395.3 · 34-hour restart · verified 2026-09-08