CDL General Knowledge Test Questions and Answers
CDL General Knowledge answers for independent study: review 132 questions on the federal rules behind the test, each cited to 49 CFR. Your state CDL manual adds state-specific driving topics.
Federal rules behind the CDL general knowledge test, from 49 CFR Parts 382, 383, 391, 392, 393, 395 and 396 (eCFR current as of 2026-10-27): vehicle groups A, B and C, the CLP, endorsements and restriction codes, disqualifications, alcohol and drug limits, driving rules, warning devices, tires, cargo securement, hours of service and vehicle inspection. State CDL manuals add state-specific driving topics not covered here.
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01How many red reflective triangles should you carry?
Three. Under 49 CFR 393.95(f), a truck or bus may meet the warning-device rule with three bidirectional emergency reflective triangles; the other option the rule lists is at least 6 fusees.
VERIFIED AGAINST THE SOURCE
“Warning devices for stopped vehicles. Except as provided in paragraph (g) of this section, one of the following options must be used: [...] Three bidirectional emergency reflective triangles that conform to the requirements of Federal Motor Vehicle Safety Standard No. 125 [...] At least 6 fusees.”
— 49 CFR 393.95, Emergency equipment on all power units (eCFR current as of 2026-10-27) ↗02Where should your reflectors be placed when stopped on a divided highway?
At about 10 feet, 100 feet and 200 feet behind the vehicle, toward approaching traffic. 49 CFR 392.22(b)(2)(v) says that on a divided or one-way highway the devices go 200 feet and 100 feet back toward approaching traffic, plus one on the traffic side within 10 feet of the rear.
VERIFIED AGAINST THE SOURCE
“one warning device at a distance of 200 feet and one warning device at a distance of 100 feet in a direction toward approaching traffic in the center of the lane or shoulder occupied by the commercial motor vehicle. He/she shall place one warning device at the traffic side of the commercial motor vehicle within 10 feet of the rear of the commercial motor vehicle.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗03You must park on the side of a level, straight, two lane road. Where should you place the three reflective triangles?
One about 10 feet behind the vehicle on the traffic side, one about 100 feet behind it, and one about 100 feet ahead of it. 49 CFR 392.22(b)(1) sets 4 paces (about 10 feet) and 40 paces (about 100 feet) toward approaching traffic, and 40 paces (about 100 feet) in the direction away from approaching traffic.
VERIFIED AGAINST THE SOURCE
“One on the traffic side of and 4 paces (approximately 3 meters or 10 feet) from the stopped commercial motor vehicle in the direction of approaching traffic [...] One at 40 paces (approximately 30 meters or 100 feet) from the stopped commercial motor vehicle in the center of the traffic lane or shoulder occupied by the commercial motor vehicle and in the direction of approaching traffic [...] One at 40 paces (approximately 30 meters or 100 feet) from the stopped commercial motor vehicle in the center of the traffic lane or shoulder occupied by the commercial motor vehicle and in the direction away from approaching traffic”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗04You must stop on a hill or curve on a two-lane, two-way road. How far should you place reflective triangles?
Place the warning device toward the hill or curve, 100 to 500 feet from the vehicle. 49 CFR 392.22(b)(2) says that when a CMV stops within 500 feet of a curve, hill crest or other obstruction to view, the device goes in the direction of the obstruction 100 to 500 feet away. Some answer lists say only 'within 500 feet behind you'; 49 CFR 392.22 sets a range of 100 to 500 feet toward the obstruction.
VERIFIED AGAINST THE SOURCE
“If a commercial motor vehicle is stopped within 500 feet of a curve, crest of a hill, or other obstruction to view, the driver shall place the warning signal required by paragraph (b)(1) of this section in the direction of the obstruction to view a distance of 100 feet to 500 feet from the stopped commercial motor vehicle”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗05If you must stop on a road or the shoulder of any road, you must put out your emergency warning devices within how many minutes?
Within 10 minutes. 49 CFR 392.22(b)(1) requires the driver to place the warning devices as soon as possible, but in any event within 10 minutes of stopping.
VERIFIED AGAINST THE SOURCE
“the driver shall, as soon as possible, but in any event within 10 minutes, place the warning devices required by § 393.95 of this subchapter”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗06You should always turn on your emergency four-way flashers when you:
Stop on the road or its shoulder. 49 CFR 392.22(a) requires the driver to turn on the hazard warning flashers right away and keep them flashing until the warning devices are placed.
VERIFIED AGAINST THE SOURCE
“the driver of the stopped commercial motor vehicle shall immediately activate the vehicular hazard warning signal flashers and continue the flashing until the driver places the warning devices required by paragraph (b) of this section”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗07When stopping at a railroad-highway crossing, drivers must stop no closer than how many feet to the tracks?
15 feet. 49 CFR 392.10(a) requires the vehicles it covers, such as passenger buses and certain placarded hazmat vehicles, to stop within 50 feet of the tracks but not closer than 15 feet.
VERIFIED AGAINST THE SOURCE
“Stops the commercial motor vehicle within 50 feet of, and not closer than 15 feet to, the tracks; thereafter listens and looks in each direction along the tracks for an approaching train”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗08To stop for railroad tracks, a bus driver should stop ___ to ___ feet before the nearest track.
15 to 50 feet. 49 CFR 392.10(a) covers every bus transporting passengers: the driver stops within 50 feet of, and not closer than 15 feet to, the tracks, then listens and looks both ways for a train.
VERIFIED AGAINST THE SOURCE
“Every bus transporting passengers, [...] Stops the commercial motor vehicle within 50 feet of, and not closer than 15 feet to, the tracks; thereafter listens and looks in each direction along the tracks for an approaching train”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗09When driving a bus across railroad tracks, you:
Must not change gears while crossing. 49 CFR 392.10(a) says to cross in a gear that lets the vehicle clear the tracks without a gear change. Some answer lists limit this to buses with a manual transmission; 49 CFR 392.10 says the driver must not shift gears while crossing, with no transmission exception.
VERIFIED AGAINST THE SOURCE
“When it is safe to do so, the driver may drive the commercial motor vehicle across the tracks in a gear that permits the commercial motor vehicle to complete the crossing without a change of gears. The driver must not shift gears while crossing the tracks.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗10When must you not change gears while crossing railroad tracks?
Never shift while crossing, whatever the transmission. 49 CFR 392.10(a) says to pick a gear that completes the crossing without a change of gears. Some answer lists say only 'if your bus has a manual transmission'; 49 CFR 392.10 forbids shifting while crossing with no transmission exception.
VERIFIED AGAINST THE SOURCE
“When it is safe to do so, the driver may drive the commercial motor vehicle across the tracks in a gear that permits the commercial motor vehicle to complete the crossing without a change of gears. The driver must not shift gears while crossing the tracks.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗11A full stop is required at a railroad grade crossing when:
The vehicle or its cargo is one the regulations require to stop. 49 CFR 392.10(a) lists them, including every bus transporting passengers and vehicles that must be marked or placarded for certain hazardous materials.
VERIFIED AGAINST THE SOURCE
“Every bus transporting passengers, [...] Every commercial motor vehicle which, in accordance with the regulations of the Department of Transportation, is required to be marked or placarded with one of the following classifications”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗12A first railroad-highway grade crossing violation results in:
Disqualification for no less than 60 days. Table 3 to 49 CFR 383.51 sets 60 days for a first conviction, 120 days for a second and 1 year for a third within 3 years.
VERIFIED AGAINST THE SOURCE
“(1) The driver is not required to always stop, but fails to slow down and check that tracks are clear of an approaching train * * * No less than 60 days No less than 120 days No less than 1 year.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗13A second railroad-highway grade crossing violation within three years results in:
Disqualification for no less than 120 days. Table 3 to 49 CFR 383.51 sets that period for a second conviction in a separate incident within a 3-year period.
VERIFIED AGAINST THE SOURCE
“For a second conviction of any combination of offenses in this Table in a separate incident within a 3-year period [...] (1) The driver is not required to always stop, but fails to slow down and check that tracks are clear of an approaching train * * * No less than 60 days No less than 120 days No less than 1 year.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗14A third railroad-highway grade crossing violation within three years results in:
Disqualification for no less than 1 year. Table 3 to 49 CFR 383.51 sets that period for a third or later conviction within a 3-year period.
VERIFIED AGAINST THE SOURCE
“(1) The driver is not required to always stop, but fails to slow down and check that tracks are clear of an approaching train * * * No less than 60 days No less than 120 days No less than 1 year.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗15Two serious traffic violations in three years can mean no CDL for how long?
At least 60 days. Table 2 to 49 CFR 383.51 disqualifies a driver for 60 days on a second serious traffic violation in a separate incident within 3 years while driving a CMV.
VERIFIED AGAINST THE SOURCE
“For a second conviction of any combination of offenses in this Table in a separate incident within a 3-year period while operating a CMV, a person required to have a CLP or CDL and a CLP or CDL holder must be disqualified from operating a CMV for [...] (1) Speeding excessively, involving any speed of 24.1 kmph (15 mph) or more above the regulated or posted speed limit 60 days 60 days 120 days 120 days.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗16Three serious traffic violations in three years can mean no CDL for how long?
At least 120 days. Table 2 to 49 CFR 383.51 disqualifies a driver for 120 days on a third or later serious traffic violation within 3 years.
VERIFIED AGAINST THE SOURCE
“(1) Speeding excessively, involving any speed of 24.1 kmph (15 mph) or more above the regulated or posted speed limit 60 days 60 days 120 days 120 days.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗17You will lose your CDL for at least 60 days if you are convicted of:
Two serious traffic violations, in separate incidents within 3 years, while driving a CMV. Table 2 to 49 CFR 383.51 sets the 60-day period for a second conviction.
VERIFIED AGAINST THE SOURCE
“For a second conviction of any combination of offenses in this Table in a separate incident within a 3-year period while operating a CMV, a person required to have a CLP or CDL and a CLP or CDL holder must be disqualified from operating a CMV for”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗18How long do you lose your CDL driving privileges if you are convicted of a second DUI?
For life. Table 1 to 49 CFR 383.51 disqualifies a driver for life on a second conviction for driving under the influence in a separate incident.
VERIFIED AGAINST THE SOURCE
“For a second conviction or refusal to be tested in a separate incident of any combination of offenses in this Table while operating a CMV, a person required to have a CLP or CDL and a CLP or CDL holder must be disqualified from operating a CMV for [...] (1) Being under the influence of alcohol as prescribed by State law * * * 1 year 1 year 3 years Life Life.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗19If you have been convicted of driving a commercial vehicle under the influence of alcohol or drugs, you will lose your CDL for:
1 year for a first conviction, or 3 years if you were hauling placarded hazardous materials. Table 1 to 49 CFR 383.51 sets these periods for both alcohol and controlled substances.
VERIFIED AGAINST THE SOURCE
“(1) Being under the influence of alcohol as prescribed by State law * * * 1 year 1 year 3 years Life Life. (2) Being under the influence of a controlled substance * * * 1 year 1 year 3 years Life Life.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗20If you leave the scene of an accident and you are convicted of this offense, how long will you be disqualified from driving a CMV?
1 year for a first conviction (3 years if hauling hazardous materials, life for a second). Table 1 to 49 CFR 383.51 lists leaving the scene of an accident as a major offense.
VERIFIED AGAINST THE SOURCE
“(5) Leaving the scene of an accident * * * 1 year 1 year 3 years Life Life.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗21How long do you lose your CDL if you use a CMV to commit a felony involving controlled substances?
For life, with no chance of 10-year reinstatement. Table 1 to 49 CFR 383.51 sets that period for using the vehicle in a felony involving making, distributing or dispensing a controlled substance.
VERIFIED AGAINST THE SOURCE
“Using the vehicle in the commission of a felony involving manufacturing, distributing, or dispensing a controlled substance * * * Life-not eligible for 10-year reinstatement”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗22How long will you lose your CDL if you have committed your first violation of an out-of-service order?
At least 180 days, up to 1 year. Table 4 to 49 CFR 383.51 sets this for a first violation while hauling nonhazardous materials; for hazmat or a 16-plus passenger vehicle it is 180 days to 2 years.
VERIFIED AGAINST THE SOURCE
“(1) Violating a driver or vehicle out-of-service order while transporting nonhazardous materials No less than 180 days or more than 1 year No less than 2 years or more than 5 years No less than 3 years or more than 5 years.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗23How long will you lose your CDL if you have committed two violations of an out-of-service order in a 10 year period?
At least 2 years, up to 5 years. Table 4 to 49 CFR 383.51 sets this for a second violation in a separate incident within 10 years while hauling nonhazardous materials.
VERIFIED AGAINST THE SOURCE
“For a second conviction in a separate incident within a 10-year period while operating a CMV [...] (1) Violating a driver or vehicle out-of-service order while transporting nonhazardous materials No less than 180 days or more than 1 year No less than 2 years or more than 5 years No less than 3 years or more than 5 years.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗24How long will you lose your CDL if you have committed three or more violations of an out-of-service order in a 10 year period?
At least 3 years, up to 5 years. Table 4 to 49 CFR 383.51 sets this for a third or later violation within 10 years.
VERIFIED AGAINST THE SOURCE
“(1) Violating a driver or vehicle out-of-service order while transporting nonhazardous materials No less than 180 days or more than 1 year No less than 2 years or more than 5 years No less than 3 years or more than 5 years.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗25For a 2nd violation of an out-of-service order in 10 years, you will lose your CDL for at least:
2 years when hauling nonhazardous materials. Table 4 to 49 CFR 383.51 sets no less than 2 years for a second violation within 10 years. Some answer lists say 1 year (and 90 days for a first offense); 49 CFR 383.51 now says 2 years for a second violation and 180 days for a first.
VERIFIED AGAINST THE SOURCE
“For a second conviction in a separate incident within a 10-year period while operating a CMV [...] (1) Violating a driver or vehicle out-of-service order while transporting nonhazardous materials No less than 180 days or more than 1 year No less than 2 years or more than 5 years No less than 3 years or more than 5 years.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗26Your CDL will be disqualified after ___ or more convictions of any state law on hand-held mobile telephone use while operating a CMV.
Two, in separate incidents within 3 years. Table 2 to 49 CFR 383.51 lists hand-held phone use as a serious traffic violation: 60 days for a second conviction and 120 days for a third.
VERIFIED AGAINST THE SOURCE
“(10) Violating a State or local law or ordinance on motor vehicle traffic control restricting or prohibiting the use of a hand-held mobile telephone while driving a CMV. 2 60 days Not applicable 120 days”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗27After how many convictions of any state law on hand-held mobile phone use will the CDL disqualify you, and for how long?
Two convictions within 3 years bring a 60-day disqualification; a third brings 120 days. Table 2 to 49 CFR 383.51 sets these periods. Some answer lists say 120 days; 49 CFR 383.51 says 60 days for the second conviction and 120 days for a third or later one.
VERIFIED AGAINST THE SOURCE
“(10) Violating a State or local law or ordinance on motor vehicle traffic control restricting or prohibiting the use of a hand-held mobile telephone while driving a CMV. 2 60 days Not applicable 120 days”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗28Your CDL will be disqualified after two or more convictions of any state law on texting while operating a CMV. Disqualification is ___ days for the second offense within 3 years and ___ days for three or more offenses within 3 years.
60 days and 120 days. Table 2 to 49 CFR 383.51 lists texting while driving a CMV as a serious traffic violation with those periods.
VERIFIED AGAINST THE SOURCE
“Violating a State or local law or ordinance on motor vehicle traffic control prohibiting texting while driving a CMV. 2 60 days Not applicable 120 days Not applicable.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗29Are you allowed to have more than one license?
No. 49 CFR 383.21 says no person who drives a commercial motor vehicle may have more than one driver's license at any time.
VERIFIED AGAINST THE SOURCE
“No person who operates a commercial motor vehicle shall at any time have more than one driver's license.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗30A driver can have: two licenses, one for automobiles and one for trucks; an automobile license from one state and a CDL from another; a license for each state they will drive in; or only one license?
Only one license. 49 CFR 383.21 bars a commercial driver from having more than one driver's license at any time.
VERIFIED AGAINST THE SOURCE
“No person who operates a commercial motor vehicle shall at any time have more than one driver's license.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗31When must you notify your employer of a conviction for any traffic violations?
Within 30 days of the conviction, in any type of vehicle, for any traffic violation except parking. 49 CFR 383.31(a) sets this rule.
VERIFIED AGAINST THE SOURCE
“who is convicted of violating, in any type of motor vehicle, a State or local law relating to motor vehicle traffic control (other than a parking violation), shall notify his/her current employer of such conviction. The notification must be made within 30 days after the date that the person has been convicted.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗32If you pay a parking ticket, do you have to notify your employer?
No. 49 CFR 383.31(a) requires notice within 30 days for traffic convictions other than a parking violation.
VERIFIED AGAINST THE SOURCE
“who is convicted of violating, in any type of motor vehicle, a State or local law relating to motor vehicle traffic control (other than a parking violation), shall notify his/her current employer of such conviction.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗33When must you notify your employer if your license is suspended, revoked, cancelled, or if you are disqualified from driving?
Before the end of the business day after the day you get notice. 49 CFR 383.33 sets that deadline. Some answer lists say within 2 business days; 49 CFR 383.33 says before the end of the business day following the day the notice was received.
VERIFIED AGAINST THE SOURCE
“shall notify his/her current employer of such suspension, revocation, cancellation, lost privilege, or disqualification. The notification must be made before the end of the business day following the day the employee received notice of the suspension, revocation, cancellation, lost privilege, or disqualification.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗34If you are disqualified from driving, what must you tell your employer, and when?
Tell your current employer of the disqualification before the end of the business day after the day you get notice. 49 CFR 383.33 sets that deadline. Some answer lists say within two business days; 49 CFR 383.33 says before the end of the following business day.
VERIFIED AGAINST THE SOURCE
“shall notify his/her current employer of such suspension, revocation, cancellation, lost privilege, or disqualification. The notification must be made before the end of the business day following the day the employee received notice of the suspension, revocation, cancellation, lost privilege, or disqualification.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗35How much driving history must you give your employer?
Your employment history for the 10 years before you apply. 49 CFR 383.35(c) requires the applicant to give this to the prospective employer.
VERIFIED AGAINST THE SOURCE
“The following employment history information for the 10 years preceding the date the application is submitted shall be presented to the prospective employer by the applicant”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗36You will be placed out of service for 24 hours if your blood alcohol concentration is at least:
Any detectable amount. 49 CFR 392.5 bars any measured alcohol concentration or detected presence of alcohol while on duty, and a violation means 24 hours out of service.
VERIFIED AGAINST THE SOURCE
“Use alcohol, be under the influence of alcohol, or have any measured alcohol concentration or detected presence of alcohol, while on duty, or operating, or in physical control of a commercial motor vehicle [...] driver who is found to be in violation of the provisons of paragraph (a) or (b) of this section shall be placed out-of-service immediately for a period of 24 hours”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗37You will be placed out of service for 24 hours if your blood alcohol concentration is:
Any detectable amount. 49 CFR 392.5 puts a driver out of service for 24 hours for any measured alcohol concentration or detected presence of alcohol while on duty. Some answer lists say at least.04; 0.04 is the 49 CFR 382.201 limit for safety-sensitive duty, but 49 CFR 392.5 applies the 24-hour rule to any detectable amount.
VERIFIED AGAINST THE SOURCE
“No driver shall report for duty or remain on duty requiring the performance of safety-sensitive functions while having an alcohol concentration of 0.04 or greater.”
— 49 CFR 382.201, Alcohol concentration (eCFR current as of 2026-10-27) ↗38How long will you be put out of service if you have any detectable amount of alcohol under .04%?
24 hours. 49 CFR 392.5 places a driver out of service for 24 hours for any detected alcohol while on duty; at 0.04 or more, 49 CFR 382.201 also bars safety-sensitive duty.
VERIFIED AGAINST THE SOURCE
“No driver shall report for duty or remain on duty requiring the performance of safety-sensitive functions while having an alcohol concentration of 0.04 or greater.”
— 49 CFR 382.201, Alcohol concentration (eCFR current as of 2026-10-27) ↗39If you are stopped at a roadside rest area and found to have a BAC (Blood Alcohol Concentration) of 0.02, you will: be placed out of service for 24 hours, be placed out of service for 72 hours, or be in deep trouble with your dispatcher?
Be placed out of service for 24 hours. 49 CFR 392.5 bars any detected alcohol while on duty or in control of a CMV, and a violation means 24 hours out of service.
VERIFIED AGAINST THE SOURCE
“Use alcohol, be under the influence of alcohol, or have any measured alcohol concentration or detected presence of alcohol, while on duty, or operating, or in physical control of a commercial motor vehicle [...] driver who is found to be in violation of the provisons of paragraph (a) or (b) of this section shall be placed out-of-service immediately for a period of 24 hours”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗40You are required to inspect your truck within how many miles after beginning the trip?
Within the first 50 miles. 49 CFR 392.9(b) requires inspecting the cargo and its securement devices within the first 50 miles of a trip. Some answer lists say 25 miles; 49 CFR 392.9 says 50 miles.
VERIFIED AGAINST THE SOURCE
“Inspect the cargo and the devices used to secure the cargo within the first 50 miles after beginning a trip and cause any adjustments to be made to the cargo or load securement devices as necessary”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗41Once you start your trip, you must inspect the securement of your cargo within how many miles?
50 miles, then again every 3 hours or 150 miles (or at a change of duty status), whichever comes first. 49 CFR 392.9(b) sets both checks.
VERIFIED AGAINST THE SOURCE
“Inspect the cargo and the devices used to secure the cargo within the first 50 miles after beginning a trip and cause any adjustments to be made to the cargo or load securement devices as necessary [...] driven for 3 hours; or ( iii ) The commercial motor vehicle has been driven for 150 miles, whichever occurs first.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗42Safety inspection: drivers of trucks and truck tractors when transporting cargo must inspect the securement of the cargo within the first ___ of a trip and every ___ or every ___ (whichever comes first) after.
Within the first 50 miles, then every 3 hours or every 150 miles, whichever comes first. 49 CFR 392.9(b) also requires a re-check when the driver changes duty status.
VERIFIED AGAINST THE SOURCE
“Inspect the cargo and the devices used to secure the cargo within the first 50 miles after beginning a trip and cause any adjustments to be made to the cargo or load securement devices as necessary [...] driven for 3 hours; or ( iii ) The commercial motor vehicle has been driven for 150 miles, whichever occurs first.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗43You must inspect your cargo:
Within the first 50 miles of a trip, then again every 3 hours or 150 miles, or at a change of duty status, whichever comes first. 49 CFR 392.9(b) sets these checks.
VERIFIED AGAINST THE SOURCE
“Inspect the cargo and the devices used to secure the cargo within the first 50 miles after beginning a trip and cause any adjustments to be made to the cargo or load securement devices as necessary [...] Reexamine the commercial motor vehicle's cargo and its load securement devices during the course of transportation [...] driven for 3 hours; or ( iii ) The commercial motor vehicle has been driven for 150 miles, whichever occurs first.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗44Should the pre-trip inspection report from the last driver be reviewed during your pre-trip inspection?
Yes. 49 CFR 396.13 says that before driving, the driver must be satisfied the vehicle is safe and must review the last driver vehicle inspection report when one is required.
VERIFIED AGAINST THE SOURCE
“Before driving a motor vehicle, the driver shall: ( a ) Be satisfied that the motor vehicle is in safe operating condition; [...] Review the last driver vehicle inspection report if required by”
— 49 CFR 396.13, Driver inspection (eCFR current as of 2026-10-27) ↗45You must sign the inspection report made by the previous driver only:
If the reported defects have been certified as repaired or as not needing repair. 49 CFR 396.11 requires the carrier to certify the repair (or that none is needed), and 49 CFR 396.13 has the driver sign to acknowledge that certification.
VERIFIED AGAINST THE SOURCE
“Every motor carrier or its agent shall certify on the driver vehicle inspection report which lists any defect or deficiency that the defect or deficiency has been repaired or that repair is unnecessary before the vehicle is operated again.”
— 49 CFR 396.11, Driver vehicle inspection report(s) (eCFR current as of 2026-10-27) ↗46The law requires ___ to inspect a commercial motor vehicle before a trip.
The driver. 49 CFR 396.13 says that before driving, the driver must be satisfied that the vehicle is in safe operating condition.
VERIFIED AGAINST THE SOURCE
“Before driving a motor vehicle, the driver shall: ( a ) Be satisfied that the motor vehicle is in safe operating condition;”
— 49 CFR 396.13, Driver inspection (eCFR current as of 2026-10-27) ↗47If you work for an interstate carrier, you must complete an after-trip inspection report that specifies, for each bus:
Any defect or deficiency that would affect safe operation or cause a mechanical breakdown. 49 CFR 396.11(a) requires a report for each vehicle driven that day; no report is needed if no defect was found or reported.
VERIFIED AGAINST THE SOURCE
“The report must identify the vehicle and list any defect or deficiency discovered by or reported to the driver which would affect the safety of operation of the vehicle or result in its mechanical breakdown. If a driver operates more than one vehicle during the day, a report must be prepared for each vehicle operated. Drivers are not required to prepare a report if no defect or deficiency is discovered by or reported to the driver.”
— 49 CFR 396.11, Driver vehicle inspection report(s) (eCFR current as of 2026-10-27) ↗48After driving for 11 hours or being on duty for 14 hours, you may not drive until?
You have taken 10 consecutive hours off duty. 49 CFR 395.3(a) caps driving at 11 hours within the 14-hour window that starts after 10 consecutive hours off duty.
VERIFIED AGAINST THE SOURCE
“Start of work shift. A driver may not drive without first taking 10 consecutive hours off duty [...] A driver may not drive after a period of 14 consecutive hours after coming on-duty following 10 consecutive hours off-duty. [...] A driver may drive a total of 11 hours during the period specified in paragraph (a)(2) of this section.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗49Under federal rules, you aren't eligible to drive after being on duty for how many hours?
60 hours in any 7 consecutive days, or 70 hours in any 8 consecutive days if the carrier runs vehicles every day of the week. 49 CFR 395.3(b) sets these limits for property-carrying drivers.
VERIFIED AGAINST THE SOURCE
“Having been on duty 60 hours in any period of 7 consecutive days if the employing motor carrier does not operate commercial motor vehicles every day of the week [...] Having been on duty 70 hours in any period of 8 consecutive days if the employing motor carrier operates commercial motor vehicles every day of the week”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗50What are the hours of service rules for property carrying drivers?
Up to 11 hours of driving after 10 consecutive hours off duty, no driving after the 14th hour on duty, no driving after 60 hours on duty in 7 days or 70 hours in 8 days, and a restart after 34 or more consecutive hours off. 49 CFR 395.3 sets these limits.
VERIFIED AGAINST THE SOURCE
“A driver may drive a total of 11 hours during the period specified in paragraph (a)(2) of this section. [...] A driver may not drive after a period of 14 consecutive hours after coming on-duty following 10 consecutive hours off-duty. [...] Having been on duty 60 hours in any period of 7 consecutive days if the employing motor carrier does not operate commercial motor vehicles every day of the week [...] Any period of 7 consecutive days may end with the beginning of an off-duty period of 34 or more consecutive hours.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗51When should you wear seat belts?
Any time you drive a CMV that has a seat belt at the driver's seat. 49 CFR 392.16(a) bars driving unless the driver is properly restrained by the seat belt.
VERIFIED AGAINST THE SOURCE
“No driver shall operate a commercial motor vehicle, and a motor carrier shall not require or permit a driver to operate a commercial motor vehicle, that has a seat belt assembly installed at the driver's seat unless the driver is properly restrained by the seat belt assembly.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗52True or false: a seatbelt is not required for a CDL driver over 35.
False. 49 CFR 392.16(a) requires every CMV driver to wear the seat belt installed at the driver's seat, with no age exception.
VERIFIED AGAINST THE SOURCE
“No driver shall operate a commercial motor vehicle, and a motor carrier shall not require or permit a driver to operate a commercial motor vehicle, that has a seat belt assembly installed at the driver's seat unless the driver is properly restrained by the seat belt assembly.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗53Text messages: are permitted if asking a question, are not permitted, may be sent if they are short, or are encouraged?
Are not permitted while driving. 49 CFR 392.80 bans texting while driving a CMV, except to communicate with law enforcement or other emergency services.
VERIFIED AGAINST THE SOURCE
“No driver shall engage in texting while driving. [...] Emergency exception. Texting while driving is permissible by drivers of a commercial motor vehicle when necessary to communicate with law enforcement officials or other emergency services.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗54Under federal regulations, when are you allowed to hold a cell phone while driving a CMV?
To start or end a call by pressing a single button, or to reach law enforcement or emergency services. 49 CFR 383.5 says pressing a single button to initiate or terminate a voice communication is not texting, and 49 CFR 392.82 allows hand-held phone use when needed to contact law enforcement or emergency services; any other hand-held use while driving a CMV is banned.
VERIFIED AGAINST THE SOURCE
“Pressing a single button to initiate or terminate a voice communication using a mobile telephone”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗55What does a commercial learner's permit (CLP) authorize its holder to do?
Operate a class of commercial motor vehicle only when accompanied by a valid CDL holder, for behind-the-wheel training. 49 CFR 383.5 says a CLP authorizes the individual to operate a class of CMV "when accompanied by a holder of a valid CDL for purposes of behind-the-wheel training."
VERIFIED AGAINST THE SOURCE
“authorizes the individual to operate a class of a commercial motor vehicle when accompanied by a holder of a valid CDL for purposes of behind-the-wheel training”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗56A tractor with a gross combination weight rating of 80,000 pounds pulls a trailer rated at 34,000 pounds GVWR. Which CDL group is required?
Group A (combination vehicle). Group A covers a GCWR of 26,001 pounds or more where the towed unit has a GVWR of more than 10,000 pounds.
VERIFIED AGAINST THE SOURCE
“Combination Vehicle (Group A)—having a gross combination weight rating or gross combination weight of 11,794 kilograms or more (26,001 pounds or more), whichever is greater, inclusive of a towed unit(s) with a gross vehicle weight rating or gross vehicle weight of more than 4,536 kilograms (10,000 pounds)”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗57A single straight truck has a GVWR of 33,000 pounds and tows nothing. Which CDL group covers it?
Group B (heavy straight vehicle). Group B is a single vehicle with a GVWR of 26,001 pounds or more.
VERIFIED AGAINST THE SOURCE
“Heavy Straight Vehicle (Group B)—having a gross vehicle weight rating or gross vehicle weight of 11,794 or more kilograms (26,001 pounds or more)”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗58A 15-passenger van plus the driver (16 people total) weighs well under 26,001 pounds. Does it need a CDL, and which group?
Yes, Group C. Group C covers small vehicles that do not meet Group A or B but are designed to carry 16 or more passengers, including the driver.
VERIFIED AGAINST THE SOURCE
“Is designed to transport 16 or more passengers, including the driver; or”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗59True or false: a pickup truck under 10,001 pounds can still be a commercial motor vehicle requiring a CDL if it hauls placarded hazardous materials.
True. Under 49 CFR 383.5 a vehicle "of any size" used to transport hazardous materials (as defined in Part 383) is a CMV.
VERIFIED AGAINST THE SOURCE
“Hazardous materials means any material that has been designated as hazardous under 49 U.S.C. 5103 and is required to be placarded under subpart F of 49 CFR part 172”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗60Bobtailing (driving a tractor with no trailer), is the tractor's GCWR used to decide whether it is a CMV?
No. The GCWR of the power unit is not used to define a CMV when the power unit is not towing another vehicle.
VERIFIED AGAINST THE SOURCE
“The GCWR of the power unit will not be used to define a commercial motor vehicle when the power unit is not towing another vehicle.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗61How many driver's licenses may a CMV operator hold at one time?
Only one. No person who operates a CMV may at any time have more than one driver's license, and the driver qualification rule requires a license issued by only one State.
VERIFIED AGAINST THE SOURCE
“Has a currently valid commercial motor vehicle operator's license issued only by one State or jurisdiction;”
— 49 CFR 391.11, General qualifications of drivers (eCFR current as of 2026-10-27) ↗62A CLP holder is driving a Group B truck for training. Where must the supervising CDL holder be?
Physically present in the front seat next to the CLP holder at all times.
VERIFIED AGAINST THE SOURCE
“The CDL holder must at all times be physically present in the front seat of the vehicle next to the CLP holder”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗63What is the minimum age to hold a CLP under the federal rule?
18 years of age. 49 CFR 383.25 states the CLP holder must be 18 years of age or older.
VERIFIED AGAINST THE SOURCE
“The CLP holder must be 18 years of age or older.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗64Which endorsements are allowed on a CLP?
Only Passenger (P), School bus (S), and Tank vehicle (N). All other federal endorsements are prohibited on a CLP.
VERIFIED AGAINST THE SOURCE
“All other Federal endorsements are prohibited on a CLP.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗65A CLP holder with an N endorsement is asked to drive a tanker that still holds residue from a hazardous material. May they?
No. A CLP holder with an N endorsement may operate only an empty tank vehicle and may not operate one that previously held hazardous materials and has not been purged.
VERIFIED AGAINST THE SOURCE
“A CLP holder with an N endorsement may only operate an empty tank vehicle and is prohibited from operating any tank vehicle that previously contained hazardous materials that has not been purged of any residue.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗66Can a CLP holder drive a CMV that is carrying placarded hazardous materials?
No. The CLP holder may not operate a CMV transporting hazardous materials as defined in 49 CFR 383.5.
VERIFIED AGAINST THE SOURCE
“The CLP holder does not operate a commercial motor vehicle transporting hazardous materials as defined in § 383.5”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗67For how long may a CLP be valid before the holder must retake the knowledge tests?
No more than one year from the initial date of issuance.
VERIFIED AGAINST THE SOURCE
“The CLP must be valid for no more than one year from the initial date of issuance without requiring the CLP holder to retake the general and endorsement knowledge tests.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗68After a CLP is first issued, how soon can the holder take the CDL skills test?
Not in the first 14 days. The CLP holder is not eligible to take the skills test in the first 14 days after initial issuance.
VERIFIED AGAINST THE SOURCE
“The CLP holder is not eligible to take the CDL skills test in the first 14 days after initial issuance of the CLP.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗69A CDL holder is convicted of running a red light while driving their personal car. Must they tell their employer?
Yes, in writing within 30 days. Any traffic-control conviction (other than parking) in any type of motor vehicle must be reported to the current employer within 30 days.
VERIFIED AGAINST THE SOURCE
“The notification to the employer must be made in writing”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗70A driver's CDL is suspended. By when must the driver notify their employer?
Before the end of the business day following the day the driver received notice of the suspension.
VERIFIED AGAINST THE SOURCE
“The notification must be made before the end of the business day following the day the employee received notice of the suspension, revocation, cancellation, lost privilege, or disqualification.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗71An employer knows a driver is under an out-of-service order. May the employer let that driver operate a CMV?
No. An employer must not allow a driver to operate a CMV while the driver, the vehicle, or the carrier operation is subject to an out-of-service order.
VERIFIED AGAINST THE SOURCE
“During any period in which the driver, or the CMV the driver is operating, or the motor carrier operation, is subject to an out-of-service order.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗72What is the disqualification for a first conviction of driving a CMV under the influence of alcohol (not hauling hazmat)?
1 year. Table 1 to 49 CFR 383.51 sets 1 year for a first conviction, 3 years if hauling placarded hazmat, and life for a second conviction.
VERIFIED AGAINST THE SOURCE
“(1) Being under the influence of alcohol as prescribed by State law * * * 1 year 1 year 3 years Life Life”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗73A driver is convicted of operating a CMV with a 0.04 alcohol concentration while hauling placarded hazardous materials. What is the first-offense disqualification?
3 years. A 0.04 or greater alcohol concentration in a CMV carries 1 year for a first offense, or 3 years if the vehicle was transporting hazardous materials.
VERIFIED AGAINST THE SOURCE
“(3) Having an alcohol concentration of 0.04 or greater while operating a CMV * * * 1 year Not applicable 3 years Life Not applicable”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗74Refusing to take an alcohol test under a state's implied consent law is treated as which kind of CDL offense?
A major offense in Table 1 to 49 CFR 383.51, carrying the same disqualification periods as an alcohol conviction (1 year first offense, life for a second).
VERIFIED AGAINST THE SOURCE
“(4) Refusing to take an alcohol test as required by a State or jurisdiction under its implied consent laws”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗75What happens on a second conviction for leaving the scene of an accident?
Lifetime disqualification. Table 1 lists 1 year for a first conviction (3 years with hazmat) and life for a second.
VERIFIED AGAINST THE SOURCE
“(5) Leaving the scene of an accident * * * 1 year 1 year 3 years Life Life”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗76Which offense brings a lifetime CDL disqualification with no eligibility for 10-year reinstatement?
Using the vehicle in the commission of a felony involving manufacturing, distributing, or dispensing a controlled substance (also a CMV used in human trafficking).
VERIFIED AGAINST THE SOURCE
“(10) Using a CMV in the commission of a felony involving an act or practice of severe forms of trafficking in persons”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗77Can a driver disqualified for life for a first-tier major offense (such as DUI twice) ever get the CDL back?
Possibly, after 10 years. A State may reinstate a driver disqualified for life for offenses in Table 1 (b)(1) through (8) after 10 years if the driver has completed an approved rehabilitation program.
VERIFIED AGAINST THE SOURCE
“A State may reinstate any driver disqualified for life for offenses described in paragraphs (b)(1) through (8) of this section (Table 1 to § 383.51 ) after 10 years, if that person has voluntarily entered”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗78Causing a death through negligent operation of a CMV is classed as what under 49 CFR 383.51?
A major offense (Table 1), including crimes such as motor vehicle manslaughter, homicide by motor vehicle and negligent homicide.
VERIFIED AGAINST THE SOURCE
“(8) Causing a fatality through the negligent operation of a CMV, including but not limited to the crimes of motor vehicle manslaughter”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗79How fast over the posted limit counts as "excessive speeding," a serious traffic violation for CDL holders?
15 mph or more above the regulated or posted speed limit.
VERIFIED AGAINST THE SOURCE
“(1) Speeding excessively, involving any speed of 24.1 kmph (15 mph) or more above the regulated or posted speed limit”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗80A CDL driver gets a second serious traffic violation in a CMV within 3 years. What is the disqualification?
60 days. A second serious violation within 3 years brings 60 days; a third brings 120 days.
VERIFIED AGAINST THE SOURCE
“(4) Following the vehicle ahead too closely 60 days 60 days 120 days 120 days”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗81Which of these is a serious traffic violation under Table 2: making erratic lane changes, a parking ticket, or an expired registration?
Making improper or erratic traffic lane changes. Following the vehicle ahead too closely is also on the list.
VERIFIED AGAINST THE SOURCE
“(3) Making improper or erratic traffic lane changes”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗82True or false: a conviction for using a hand-held mobile phone while driving a CMV is a serious traffic violation.
True. Violating a law restricting hand-held phone use while driving a CMV is listed in Table 2 to 49 CFR 383.51, as is texting while driving a CMV.
VERIFIED AGAINST THE SOURCE
“(9) Violating a State or local law or ordinance on motor vehicle traffic control prohibiting texting while driving a CMV.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗83What is the minimum disqualification for a first conviction of a railroad-highway grade crossing violation?
No less than 60 days. A second conviction within 3 years brings no less than 120 days, and a third no less than 1 year.
VERIFIED AGAINST THE SOURCE
“(4) The driver fails to have sufficient space to drive completely through the crossing without stopping * * * No less than 60 days No less than 120 days No less than 1 year.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗84A truck gets hung up on a raised railroad crossing because of low undercarriage clearance. Is that a disqualifying offense?
Yes. Failing to negotiate a crossing because of insufficient undercarriage clearance is a railroad-highway grade crossing offense in Table 3.
VERIFIED AGAINST THE SOURCE
“(6) The driver fails to negotiate a crossing because of insufficient undercarriage clearance * * *”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗85What is the disqualification for a first conviction of violating an out-of-service order while hauling non-hazardous cargo?
No less than 180 days and no more than 1 year. A second conviction within 10 years brings 2 to 5 years.
VERIFIED AGAINST THE SOURCE
“(1) Violating a driver or vehicle out-of-service order while transporting nonhazardous materials No less than 180 days or more than 1 year No less than 2 years or more than 5 years”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗86Which endorsement needs both a knowledge test and a skills test: double/triple trailers, hazardous materials, or passenger?
Passenger. Passenger and school bus endorsements require a knowledge and a skills test; double/triple trailers and hazardous materials require a knowledge test only.
VERIFIED AGAINST THE SOURCE
“( 5 ) School bus —a knowledge and a skills test.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗87An applicant fails the air brake section of the knowledge test. What happens on the license?
The State must restrict the CLP or CDL so the person may not operate a CMV equipped with air brakes.
VERIFIED AGAINST THE SOURCE
“If an applicant either fails the air brake component of the knowledge test, or performs the skills test in a vehicle not equipped with air brakes”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗88An applicant takes the skills test in a truck with an automatic transmission. What restriction is placed on the CDL?
A restriction from operating a CMV equipped with a manual transmission (code E).
VERIFIED AGAINST THE SOURCE
“E for No Manual transmission equipped CMV;”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗89An applicant scores 75 percent on the combination vehicle knowledge test. Can they get a Group A CLP?
No. A driver who fails the combination vehicle portion (less than 80 percent) must not be issued a Group A CLP or CDL.
VERIFIED AGAINST THE SOURCE
“A driver applicant who fails the combination vehicle portion of the knowledge test (scores less than 80 percent correct) must not be issued a Group A CLP or CDL.”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗90A CDL shows restriction code L. What can that driver not operate?
A CMV equipped with air brakes. L means "No Air brake equipped CMV"; Z means no full air brake equipped CMV.
VERIFIED AGAINST THE SOURCE
“Z for No Full air brake equipped CMV;”
— 49 CFR Part 383, Commercial Driver's License Standards; Requirements and Penalties (eCFR current as of 2026-10-27) ↗91At what alcohol concentration is a driver barred from performing safety-sensitive functions under the FMCSA testing rules?
0.04 or greater.
VERIFIED AGAINST THE SOURCE
“No driver shall report for duty or remain on duty requiring the performance of safety-sensitive functions while having an alcohol concentration of 0.04 or greater.”
— 49 CFR 382.201, Alcohol concentration (eCFR current as of 2026-10-27) ↗92A driver had a beer at lunch. How long must they wait before performing safety-sensitive functions?
At least four hours. No driver may perform safety-sensitive functions within four hours after using alcohol, and Part 392 also bars being under the influence within 4 hours before going on duty.
VERIFIED AGAINST THE SOURCE
“be under the influence of alcohol, within 4 hours before going on duty or operating, or having physical control of, a commercial motor vehicle”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗93A driver's drug test specimen is found to be adulterated. May the driver remain on duty?
No. A driver who tests positive or has adulterated or substituted a specimen may not report for or remain on duty or perform a safety-sensitive function.
VERIFIED AGAINST THE SOURCE
“No driver shall report for duty, remain on duty or perform a safety-sensitive function, if the driver tests positive or has adulterated or substituted a test specimen for controlled substances.”
— 49 CFR 382.215, Controlled substances testing (eCFR current as of 2026-10-27) ↗94What is the minimum age to drive a CMV under the general driver qualification rule in 49 CFR 391.11?
21 years old.
VERIFIED AGAINST THE SOURCE
“( 1 ) Is at least 21 years old;”
— 49 CFR 391.11, General qualifications of drivers (eCFR current as of 2026-10-27) ↗95What English language ability does 49 CFR 391.11 require of a CMV driver?
Enough to converse with the general public, understand highway traffic signs and signals in English, respond to official inquiries, and make entries on reports and records.
VERIFIED AGAINST THE SOURCE
“Can read and speak the English language sufficiently to converse with the general public, to understand highway traffic signs and signals in the English language”
— 49 CFR 391.11, General qualifications of drivers (eCFR current as of 2026-10-27) ↗96Since June 23, 2025, does a CDL holder with a current medical certificate have to carry the paper certificate?
No. The CDL or CLP holder no longer needs to carry the medical examiner's certificate, and the medical certification information provided electronically by FMCSA controls.
VERIFIED AGAINST THE SOURCE
“the medical certification information provided electronically by FMCSA shall control.”
— 49 CFR 391.41, Physical qualifications for drivers (eCFR current as of 2026-10-27) ↗97A driver feels too fatigued to drive safely. What does 49 CFR 392.3 require?
The driver must not begin or continue to drive while their ability or alertness is so impaired, or likely to become impaired, by fatigue, illness or any other cause.
VERIFIED AGAINST THE SOURCE
“while the driver's ability or alertness is so impaired, or so likely to become impaired, through fatigue, illness, or any other cause, as to make it unsafe for him/her to begin or continue to operate the commercial motor vehicle.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗98When must a driver first re-inspect cargo and its securement after starting a trip?
Within the first 50 miles after beginning the trip.
VERIFIED AGAINST THE SOURCE
“Inspect the cargo and the devices used to secure the cargo within the first 50 miles after beginning a trip”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗99After the first check, how often must a driver re-examine cargo and load securement during a trip?
Whenever the driver changes duty status, or after 3 hours of driving, or after 150 miles, whichever occurs first.
VERIFIED AGAINST THE SOURCE
“The commercial motor vehicle has been driven for 150 miles, whichever occurs first.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗100A driver loads boxes into the cab so that they block the right-side window. Is this allowed?
No. Cargo or any other object must not obscure the driver's view ahead or to the right or left sides.
VERIFIED AGAINST THE SOURCE
“cargo or any other object does not obscure the driver's view ahead or to the right or left sides”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗101A bus carrying passengers approaches a railroad crossing. Where must the driver stop?
Within 50 feet of, and not closer than 15 feet to, the tracks, then listen and look both ways for a train.
VERIFIED AGAINST THE SOURCE
“( 1 ) Every bus transporting passengers,”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗102Traffic ahead is backed up just past a railroad crossing. May the driver pull onto the crossing and wait?
No. A driver must not drive onto a crossing without enough space to drive completely through it without stopping.
VERIFIED AGAINST THE SOURCE
“No driver of a commercial motor vehicle shall drive onto a highway-rail grade crossing without having sufficient space to drive completely through the crossing without stopping.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗103Fog reduces visibility on the highway. What does 49 CFR 392.14 require?
Extreme caution, and speed must be reduced when hazardous conditions such as snow, ice, fog, rain, dust or smoke affect visibility or traction.
VERIFIED AGAINST THE SOURCE
“Extreme caution in the operation of a commercial motor vehicle shall be exercised when hazardous conditions, such as those caused by snow, ice, sleet, fog, mist, rain, dust, or smoke, adversely affect visibility or traction. Speed shall be reduced when such conditions exist.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗104True or false: a CMV driver may drive without a seat belt if the trip is short.
False. A driver may not drive a CMV with a seat belt installed at the driver's seat unless properly restrained by it.
VERIFIED AGAINST THE SOURCE
“that has a seat belt assembly installed at the driver's seat unless the driver is properly restrained by the seat belt assembly.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗105A truck breaks down on the shoulder of a highway. What must the driver do immediately?
Turn on the hazard warning flashers. Warning devices must then be placed as soon as possible and in any event within 10 minutes.
VERIFIED AGAINST THE SOURCE
“the driver shall, as soon as possible, but in any event within 10 minutes, place the warning devices required by § 393.95”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗106On a two-lane road, where are the three warning triangles placed around a stopped truck?
One on the traffic side about 10 feet (4 paces) from the truck toward approaching traffic, one about 100 feet (40 paces) behind in the lane or shoulder, and one about 100 feet ahead in the direction away from approaching traffic.
VERIFIED AGAINST THE SOURCE
“One at 40 paces (approximately 30 meters or 100 feet) from the stopped commercial motor vehicle in the center of the traffic lane or shoulder occupied by the commercial motor vehicle and in the direction of approaching traffic; and”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗107A truck stops just past the crest of a hill. How far back should the rear warning device go?
100 to 500 feet from the truck, in the direction of the obstruction to view, when stopped within 500 feet of a hill crest or curve.
VERIFIED AGAINST THE SOURCE
“If a commercial motor vehicle is stopped within 500 feet of a curve, crest of a hill, or other obstruction to view, the driver shall place the warning signal required by paragraph (b)(1) of this section in the direction of the obstruction to view a distance of 100 feet to 500 feet”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗108On a divided or one-way highway, where are warning devices placed behind a stopped truck?
One at 200 feet and one at 100 feet toward approaching traffic, plus one at the traffic side within 10 feet of the rear of the vehicle.
VERIFIED AGAINST THE SOURCE
“one warning device at a distance of 200 feet and one warning device at a distance of 100 feet in a direction toward approaching traffic in the center of the lane or shoulder occupied by the commercial motor vehicle”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗109May a driver fuel a CMV with the engine running?
No, except when the engine must run to fuel the vehicle.
VERIFIED AGAINST THE SOURCE
“Fuel a commercial motor vehicle with the engine running, except when it is necessary to run the engine to fuel the commercial motor vehicle;”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗110When is texting while driving a CMV allowed?
Only when necessary to communicate with law enforcement officials or other emergency services. Otherwise no driver may text while driving.
VERIFIED AGAINST THE SOURCE
“Texting while driving is permissible by drivers of a commercial motor vehicle when necessary to communicate with law enforcement officials or other emergency services.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗111May a truck driver hold a mobile phone to their ear for a call while driving?
No. No driver may use a hand-held mobile telephone while driving a CMV.
VERIFIED AGAINST THE SOURCE
“No driver shall use a hand-held mobile telephone while driving a CMV.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗112A truck driver wants to give a hitchhiker a ride. What does 49 CFR 392.60 say?
Not allowed unless the motor carrier has specifically authorized it in writing. Without that, no driver may transport any person on a CMV other than a bus.
VERIFIED AGAINST THE SOURCE
“by the motor carrier under whose authority the commercial motor vehicle is being operated, no driver shall transport any person or permit any person to be transported on any commercial motor vehicle other than a bus.”
— 49 CFR Part 392, Driving of Commercial Motor Vehicles (eCFR current as of 2026-10-27) ↗113What is the minimum tread depth for a tire on the front (steering) axle of a truck?
4/32 of an inch, measured at any point on a major tread groove.
VERIFIED AGAINST THE SOURCE
“Any tire on the front wheels of a bus, truck, or truck tractor shall have a tread groove pattern depth of at least 4 ⁄ 32 of an inch when measured at any point on a major tread groove.”
— 49 CFR 393.75, Tires (eCFR current as of 2026-10-27) ↗114May a bus run with recapped or retreaded tires on its front wheels?
No. No bus may be operated with regrooved, recapped or retreaded tires on the front wheels.
VERIFIED AGAINST THE SOURCE
“No bus shall be operated with regrooved, recapped or retreaded tires on the front wheels.”
— 49 CFR 393.75, Tires (eCFR current as of 2026-10-27) ↗115During a pre-trip check a driver hears air hissing from a tire. Under 49 CFR 393.75, may the truck be operated on that tire?
No. A CMV must not be operated on a tire that is flat or has an audible leak.
VERIFIED AGAINST THE SOURCE
“Is flat or has an audible leak, or”
— 49 CFR 393.75, Tires (eCFR current as of 2026-10-27) ↗116What fire extinguisher must a power unit carry when hauling placarded hazardous materials?
One with an Underwriters' Laboratories rating of 10 B:C or more. Without hazmat, one 5 B:C extinguisher or two 4 B:C extinguishers will do.
VERIFIED AGAINST THE SOURCE
“Two fire extinguishers, each of which has an Underwriters' Laboratories rating of 4 B:C or more.”
— 49 CFR 393.95, Emergency equipment on all power units (eCFR current as of 2026-10-27) ↗117What warning devices must a truck carry for stopped-vehicle protection?
Three bidirectional emergency reflective triangles meeting FMVSS No. 125.
VERIFIED AGAINST THE SOURCE
“Three bidirectional emergency reflective triangles that conform to the requirements of Federal Motor Vehicle Safety Standard No. 125”
— 49 CFR 393.95, Emergency equipment on all power units (eCFR current as of 2026-10-27) ↗118How should cargo that is likely to roll, such as pipe or drums on their side, be restrained?
With chocks, wedges, a cradle or another equivalent means that prevents rolling.
VERIFIED AGAINST THE SOURCE
“Articles of cargo that are likely to roll must be restrained by chocks, wedges, a cradle or other equivalent means to prevent rolling.”
— 49 CFR 393.106, General requirements for securing articles of cargo (eCFR current as of 2026-10-27) ↗119A load weighs 10,000 pounds. What is the minimum aggregate working load limit of the tiedowns securing it?
5,000 pounds. The aggregate working load limit must be at least one-half the weight of the article or group of articles.
VERIFIED AGAINST THE SOURCE
“The aggregate working load limit of tiedowns used to secure an article or group of articles against movement must be at least one-half times the weight of the article or group of articles.”
— 49 CFR 393.106, General requirements for securing articles of cargo (eCFR current as of 2026-10-27) ↗120An unblocked steel beam 25 feet long is loaded on a flatbed. What is the minimum number of tiedowns?
Four: two for the first 10 feet, plus one for each additional 10 feet or fraction thereof (15 feet beyond = 2 more).
VERIFIED AGAINST THE SOURCE
“Two tiedowns if the article is longer than 10 feet (3.04 meters), and one additional tiedown for every 10 feet (3.04 meters) of article length, or fraction thereof, beyond the first 10 feet (3.04 meters) of length.”
— 49 CFR 393.110, Additional requirements for determining the minimum number of tiedowns (eCFR current as of 2026-10-27) ↗121An unblocked crate is 4 feet long and weighs 900 pounds. How many tiedowns are required at minimum?
One. One tiedown is enough for articles 5 feet or less in length and 1,100 pounds or less in weight.
VERIFIED AGAINST THE SOURCE
“One tiedown for articles 5 feet (1.52 meters) or less in length, and 1,100 pounds (500 kg) or less in weight;”
— 49 CFR 393.110, Additional requirements for determining the minimum number of tiedowns (eCFR current as of 2026-10-27) ↗122How many hours may a property-carrying CMV driver drive after 10 consecutive hours off duty?
11 hours, within the 14-hour period.
VERIFIED AGAINST THE SOURCE
“A driver may drive a total of 11 hours during the period specified in paragraph (a)(2) of this section.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗123A property-carrying driver comes on duty at 6:00 a.m. after 10 hours off. After what time may they no longer drive that shift?
8:00 p.m. A driver may not drive after 14 consecutive hours following coming on duty.
VERIFIED AGAINST THE SOURCE
“A driver may not drive after a period of 14 consecutive hours after coming on-duty following 10 consecutive hours off-duty.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗124How much off-duty time must a property-carrying driver take before starting a new work shift?
10 consecutive hours off duty.
VERIFIED AGAINST THE SOURCE
“A driver may not drive without first taking 10 consecutive hours off duty;”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗125After how many hours of driving must a property-carrying driver take a 30-minute break?
8 hours. Driving is not permitted if more than 8 hours of driving have passed without at least a consecutive 30-minute interruption.
VERIFIED AGAINST THE SOURCE
“driving is not permitted if more than 8 hours of driving time have passed without at least a consecutive 30-minute interruption in driving status.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗126A carrier runs trucks every day of the week. What is the driver's on-duty limit?
70 hours in any 8 consecutive days. Carriers that do not operate every day use 60 hours in 7 days.
VERIFIED AGAINST THE SOURCE
“Having been on duty 60 hours in any period of 7 consecutive days if the employing motor carrier does not operate commercial motor vehicles every day of the week; or”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗127How long an off-duty period restarts the 60/70-hour clock?
34 or more consecutive hours off duty.
VERIFIED AGAINST THE SOURCE
“Any period of 7 consecutive days may end with the beginning of an off-duty period of 34 or more consecutive hours.”
— 49 CFR 395.3, Maximum driving time for property-carrying vehicles (eCFR current as of 2026-10-27) ↗128When must a driver prepare a driver vehicle inspection report (DVIR)?
At the completion of each day's work, for each vehicle operated.
VERIFIED AGAINST THE SOURCE
“every driver shall prepare a report in writing at the completion of each day's work on each vehicle operated”
— 49 CFR 396.11, Driver vehicle inspection report(s) (eCFR current as of 2026-10-27) ↗129Which items must the end-of-day driver vehicle inspection report cover?
Parts including service brakes and trailer brake connections, coupling devices, wheels and rims, and emergency equipment, among others.
VERIFIED AGAINST THE SOURCE
“( ix ) Coupling devices; ( x ) Wheels and rims; ( xi ) Emergency equipment.”
— 49 CFR 396.11, Driver vehicle inspection report(s) (eCFR current as of 2026-10-27) ↗130How long must the motor carrier keep the original driver vehicle inspection report?
Three months from the date the report was prepared.
VERIFIED AGAINST THE SOURCE
“for three months from the date the written report was prepared.”
— 49 CFR 396.11, Driver vehicle inspection report(s) (eCFR current as of 2026-10-27) ↗131Before driving, what must a driver do with the last driver vehicle inspection report?
Review it, and be satisfied that the vehicle is in safe operating condition.
VERIFIED AGAINST THE SOURCE
“Review the last driver vehicle inspection report”
— 49 CFR 396.13, Driver inspection (eCFR current as of 2026-10-27) ↗132How often must a CMV pass a periodic (annual) inspection?
At least once during the preceding 12 months, with documentation on the vehicle.
VERIFIED AGAINST THE SOURCE
“at least once during the preceding 12 months and documentation of such inspection is on the vehicle.”
— 49 CFR 396.17, Periodic inspection (eCFR current as of 2026-10-27) ↗Know questions we're missing?
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