CDL Commercial Learner's Permit (CLP) Exam — Questions and Answers

Question 1: A CLP holder has an air brake restriction on their permit. This means they:

Cannot drive any vehicle with air brakes (Correct answer)
May drive air brake vehicles if their CDL supervisor has no restriction
Can operate air brake vehicles only at speeds under 45 mph
Can drive vehicles with air brakes only on private property

Correct answer: Cannot drive any vehicle with air brakes

An air brake restriction on the CLP prohibits the holder from operating any vehicle equipped with air brakes.

Question 2: A CMV driver notices the vehicle ahead brakes suddenly. Which technique is most effective for stopping quickly without losing control?

Steer around the vehicle without braking
Shift to neutral and coast to a stop
Apply firm, controlled brake pressure while steering to avoid (Correct answer)
Apply maximum brake pressure immediately to lock wheels

Correct answer: Apply firm, controlled brake pressure while steering to avoid

Controlled braking while maintaining steering allows the driver to both slow the vehicle and maneuver around the hazard if necessary.

Question 3: Which of the following correctly describes the CLP knowledge test retake policy if an applicant fails?

Must wait 7 days before retaking any failed test
Must retake all knowledge tests regardless of which one was failed
Unlimited retakes are allowed with no waiting period under federal law
State rules vary, but federal law allows states to set their own waiting periods and attempt limits (Correct answer)

Correct answer: State rules vary, but federal law allows states to set their own waiting periods and attempt limits

Federal regulations set minimum standards, but states have authority to establish their own specific waiting periods and limits on knowledge test retakes.

Question 4: Which factor most commonly causes a CMV to exceed a safe speed on a downgrade?

Incorrect gear selection before starting the descent (Correct answer)
Engine malfunction causing acceleration
Improperly inflated tires
Tailwind pushing the vehicle faster

Correct answer: Incorrect gear selection before starting the descent

If the driver selects too high a gear before the descent, engine braking is insufficient to control speed, causing the vehicle to accelerate.

Question 5: What does the four-digit identification number on a hazmat placard or orange panel represent?

The UN/NA identification number that identifies the specific hazardous material (Correct answer)
The weight of the cargo in pounds
The driver's permit number for hazmat transport
The DOT-assigned route number for hazmat vehicles

Correct answer: The UN/NA identification number that identifies the specific hazardous material

The four-digit UN/NA number (e.g., UN 1203 for gasoline) uniquely identifies the hazardous substance and allows emergency responders to look it up in the ERG.

Question 6: What does it mean when the low air pressure warning device activates in a commercial vehicle?

Air pressure has dropped below a safe level (typically 60 psi) (Correct answer)
The parking brakes have been fully released
A tire has lost pressure and needs inflation
The air compressor is working too hard

Correct answer: Air pressure has dropped below a safe level (typically 60 psi)

The low air pressure warning activates when system pressure falls to around 60 psi, signaling you must stop safely and address the problem.

Question 7: What is the safest way to prevent a tractor jackknife when braking hard on a slippery road without ABS?

Use only the trailer hand valve so the tractor brakes do not engage
Brake firmly but release and reapply before the drive wheels lock up (Correct answer)
Shift into neutral and coast to a stop
Slam the brakes as hard as possible to stop quickly

Correct answer: Brake firmly but release and reapply before the drive wheels lock up

Stab braking or threshold braking keeps drive wheels from locking, which is what causes the tractor to swing out in a jackknife.

Question 8: Why is smooth acceleration especially important when driving a commercial vehicle with a loaded trailer?

Abrupt acceleration can break trailer coupling components or cause cargo shift (Correct answer)
Smooth acceleration is required only on wet roads
Smooth acceleration helps meet fuel economy standards required by law
Engines in commercial vehicles require gradual warm-up before normal acceleration

Correct answer: Abrupt acceleration can break trailer coupling components or cause cargo shift

Sudden acceleration can stress the fifth wheel coupling, break cargo tie-downs, and cause trailer sway.

Question 9: When inspecting the rear of a trailer during a pre-trip, what should you verify about the ICC bumper (rear impact guard)?

It is not bent, cracked, or missing (Correct answer)
It is painted bright orange
It has reflective tape every 12 inches
It is exactly 22 inches from the ground

Correct answer: It is not bent, cracked, or missing

The rear impact guard must be structurally sound with no bending, cracks, or missing components to protect against underride crashes.

Question 10: What is the maximum length of a safety chain or cable used to secure a converter dolly to the lead trailer?

Exactly 10 feet regardless of trailer length
Safety chains are not required on converter dollies
Long enough to prevent the dolly from swinging wide but short enough to keep it under the trailer if the pintle hook fails (Correct answer)
As long as needed to reach the rear of the lead trailer

Correct answer: Long enough to prevent the dolly from swinging wide but short enough to keep it under the trailer if the pintle hook fails

Safety chains must be short enough to prevent the dolly from touching the ground if it separates, limiting swing and ground contact.

Question 11: When must a CDL applicant present their CLP to a skills test examiner?

At the end of testing when results are given
At the start of the skills test before any portion begins (Correct answer)
Only if asked during the on-road portion
After completing the pre-trip inspection

Correct answer: At the start of the skills test before any portion begins

The examiner must verify the applicant holds a valid CLP before administering any portion of the skills test.

Question 12: Under the FMCSA rules, what is a 'short-haul exemption' from keeping a logbook?

Drivers who operate only on private property never need a logbook
Drivers who carry only non-hazardous materials are exempt from all HOS rules
Drivers with fewer than 2 years of CDL experience are exempt for training purposes
Drivers who stay within 150 air-miles of their home terminal and return within 14 hours may use time records instead of logs (Correct answer)

Correct answer: Drivers who stay within 150 air-miles of their home terminal and return within 14 hours may use time records instead of logs

The short-haul exemption allows eligible drivers within 150 air miles who return to the home terminal within 14 hours to use time records rather than full RODS.

Question 13: You are driving in heavy rain and notice your CMV is hydroplaning. What should you do?

Accelerate to push through the water
Ease off the accelerator and steer straight until tires grip again (Correct answer)
Brake hard immediately to regain traction
Turn sharply to move onto a drier lane

Correct answer: Ease off the accelerator and steer straight until tires grip again

During hydroplaning, easing off the throttle and holding a straight path allows tires to re-contact the pavement without causing a skid.

Question 14: In a team driving operation, how must the co-driver's name be recorded?

Only on the lead driver's log
On both drivers' daily logs (Correct answer)
Only on the vehicle inspection report
Only on the shipping manifest

Correct answer: On both drivers' daily logs

In team operations, each driver must list the co-driver's name on their own daily log.

Question 15: Which of the following is a requirement for obtaining a CLP related to residency?

You must have lived in the state for at least 1 year
You must be a U.S. citizen or a legal permanent resident (Correct answer)
You need to have a permanent address in the state
You must have a social security number

Correct answer: You must be a U.S. citizen or a legal permanent resident

Federal regulations for obtaining a Commercial Learner's Permit (CLP) and subsequently a Commercial Driver's License (CDL) require applicants to demonstrate legal residency in the United States. This typically means being a U.S. citizen or a lawful permanent resident. This requirement ensures that individuals operating commercial vehicles are legally authorized to work and reside in the country, aligning with national security and immigration policies.

Question 16: If your commercial vehicle gets stuck in snow, what is the best technique to free it?

Let air out of tires for traction, then re-inflate later
Apply maximum throttle to power through
Rock rapidly between drive and reverse
Use gentle acceleration with gradual, smooth steering movements (Correct answer)

Correct answer: Use gentle acceleration with gradual, smooth steering movements

Gentle acceleration and smooth steering give the tires the best chance to grip packed snow without spinning deeper.

Question 17: What is the proper way to inspect the coupling after backing under a trailer?

Pull gently forward against the trailer brakes and look underneath to confirm the fifth wheel jaws are locked around the kingpin (Correct answer)
Wiggle the trailer by hand to see if the kingpin moves
Apply full service brakes and floor the accelerator briefly
Only visually inspect the gap between tractor and trailer from the side

Correct answer: Pull gently forward against the trailer brakes and look underneath to confirm the fifth wheel jaws are locked around the kingpin

A forward tug against locked trailer brakes plus a visual inspection underneath confirms the fifth wheel jaws have fully engaged the kingpin.

Question 18: What is the correct way to manage speed on a long downhill grade?

Apply steady constant brake pressure the entire way down
Turn off the engine to use compression braking freely
Select a low gear before the descent and use controlled brake applications (Correct answer)
Shift to a higher gear to use engine braking

Correct answer: Select a low gear before the descent and use controlled brake applications

You should choose an appropriate low gear before the descent and apply brakes intermittently rather than continuously to prevent fade.

Question 19: What is the 'applied stroke' of a brake chamber, and why does it matter?

The distance the push rod travels when brakes are fully applied; must stay within legal limits to ensure effective braking (Correct answer)
The pressure required to begin moving the push rod from its rest position
The total length of the push rod when fully retracted; determines brake chamber size selection
The speed at which brakes are applied during an emergency stop

Correct answer: The distance the push rod travels when brakes are fully applied; must stay within legal limits to ensure effective braking

Applied stroke is how far the push rod extends when brakes are applied; excessive stroke reduces braking efficiency and indicates brakes need adjustment.

Question 20: What is the minimum working load limit (WLL) that tie-downs must have in aggregate relative to the cargo they secure?

Equal to twice the cargo weight
Equal to 25% of the cargo weight
Equal to 50% of the cargo weight
Equal to the total cargo weight (Correct answer)

Correct answer: Equal to the total cargo weight

The aggregate WLL of all tie-downs securing a cargo load must be at least equal to the total weight of that cargo.

Question 21: During a pre-trip inspection, you check the windshield and find a small crack in the lower corner outside the driver's line of sight. What is the correct action?

Cover the crack with tape and note it in the logbook
The vehicle must be taken out of service immediately
Apply windshield sealer and drive normally
The vehicle may be driven but the crack must be reported on the DVIR (Correct answer)

Correct answer: The vehicle may be driven but the crack must be reported on the DVIR

A crack outside the critical driver visibility zone is a reportable defect on the DVIR but does not automatically take the vehicle out of service.

Question 22: How does nighttime supervised driving practice benefit a CLP holder's training?

It satisfies the federal night-driving certification requirement before CDL testing
Night driving practice is discouraged during the CLP period due to increased risk
It is only required for school bus and passenger endorsements
It exposes the trainee to reduced visibility conditions and different traffic patterns they will encounter commercially (Correct answer)

Correct answer: It exposes the trainee to reduced visibility conditions and different traffic patterns they will encounter commercially

Commercial drivers regularly operate at night, so practicing in low-visibility conditions under supervision prepares CLP holders for real-world commercial driving demands.

Question 23: Under FMCSA ELDT rules, which entity is responsible for reporting a CLP holder's training completion to the Training Provider Registry?

The state licensing agency upon CDL issuance
The motor carrier that employs the trainee
The registered training provider that conducted the training (Correct answer)
The CLP holder themselves, via an online portal

Correct answer: The registered training provider that conducted the training

Registered training providers are required by federal regulation to upload training completion data to the FMCSA's Training Provider Registry.

Question 24: Under the 70-hour rule, property-carrying drivers in 7-day operations may not drive after accumulating how many on-duty hours in 7 consecutive days?

84 hours
70 hours (Correct answer)
60 hours
80 hours

Correct answer: 70 hours

Drivers in 7-day operations are limited to 70 on-duty hours in any 7 consecutive days.

Question 25: Under federal hours-of-service rules, a property-carrying driver using the 60-hour/7-day limit must take how many consecutive hours off before restarting the 60-hour count?

34 hours (Correct answer)
24 hours
8 hours
10 hours

Correct answer: 34 hours

A 34-hour restart (consecutive off-duty hours) resets the 60-hour/7-day or 70-hour/8-day on-duty limit.

Question 26: During a pre-trip inspection of the lighting system, which lights must be functional for daytime operation?

Only the headlights and brake lights
Headlights only
All lights including clearance and marker lights (Correct answer)
Turn signals, brake lights, and hazard lights

Correct answer: All lights including clearance and marker lights

All required lights — including clearance lights, marker lights, turn signals, brake lights, and headlights — must function properly at all times.

Question 27: Under FMCSA regulations, the maximum overall length for a twin-trailer (doubles) combination on most interstate highways is:

No overall length limit on the combination, but each trailer is limited to 28.5 feet (Correct answer)
75 feet total combination length
65 feet total combination length
53 feet for each trailer, with no overall limit

Correct answer: No overall length limit on the combination, but each trailer is limited to 28.5 feet

Federal law grandfathers twin 28.5-foot trailers on the National Network with no set overall combination length limit, though trailer length is capped at 28.5 feet each.

Question 28: When checking the parking brake during a pre-trip inspection, what is the correct procedure?

Apply and release the parking brake three times
Check that the parking brake light illuminates on the dash
Verify the parking brake cable has no visible wear
Apply the parking brake, then attempt to move the vehicle forward with the engine running (Correct answer)

Correct answer: Apply the parking brake, then attempt to move the vehicle forward with the engine running

You verify the parking brake works by engaging it and confirming the vehicle cannot be moved forward under power.

Question 29: In rainy conditions, federal regulations and most state laws require headlights to be on whenever which condition exists?

Only when visibility drops below 500 feet
Whenever windshield wipers are in use (Correct answer)
Only at night during rain
Only during heavy downpours

Correct answer: Whenever windshield wipers are in use

Federal regulations and most state laws require headlights to be activated whenever windshield wipers are in use.

Question 30: You are loading a trailer with cargo of various weights. To ensure the vehicle is stable and handles correctly, how should the cargo be placed?

Place the heaviest items on top of the lighter items to compress the load.
Place all heavy items in the nose (front) of the trailer to secure them.
Place the heaviest items at the very rear of the trailer to improve traction.
Place the heaviest items as low as possible and centered over the axles. (Correct answer)

Correct answer: Place the heaviest items as low as possible and centered over the axles.

Proper weight distribution is critical for safety. Placing the heaviest goods on the floor and keeping them centered helps maintain a low center of gravity, which prevents rollovers. Spreading the weight out over the axles ensures that no single axle is overloaded and that the vehicle maintains proper traction and steering control.

Question 31: A driver notices the truck is pulling to one side during braking. What is the most likely cause?

The steering wheel is not centered during the stop
The load is centered too far forward
Air pressure is too high in the brake system
Uneven brake adjustment or a dragging brake on one side (Correct answer)

Correct answer: Uneven brake adjustment or a dragging brake on one side

Uneven braking force — caused by misadjusted or dragging brakes — pulls the vehicle toward the side with greater stopping force.

Question 32: What is 'brake fade' and when is it most likely to occur?

Brakes freeze in cold weather, most common in winter
Brake pedal becomes spongy due to air in lines, most common after repairs
Brakes overheat and lose effectiveness, most common on long downgrades (Correct answer)
Brakes grab suddenly, most common on wet roads

Correct answer: Brakes overheat and lose effectiveness, most common on long downgrades

Brake fade occurs when brakes overheat from excessive use, most commonly when riding the brakes on long, steep downgrades.

Question 33: When making a right turn in a large commercial vehicle, why should you position the truck slightly left before turning?

To give other drivers a warning that you are turning
To meet the minimum turning radius required by federal law
To check for traffic in the left lane before the turn
To allow the rear wheels enough room to complete the turn without hitting the curb (Correct answer)

Correct answer: To allow the rear wheels enough room to complete the turn without hitting the curb

Off-tracking causes rear wheels to follow a shorter path than the front, so swinging left provides clearance for the trailer's rear axle.

Question 34: When coupling a tractor to a semi-trailer, when should you test the connection?

By pulling gently forward in low gear with the trailer brakes locked (Correct answer)
By having a ground guide inspect the fifth wheel
Only after loading cargo onto the trailer
After driving one mile on the road

Correct answer: By pulling gently forward in low gear with the trailer brakes locked

You test the coupling by attempting to pull forward with the trailer parking brakes applied to confirm the latch is locked.

Question 35: A CMV driver is involved in a collision that does not result in any fatalities. The driver receives a moving violation citation from law enforcement. Under which of these circumstances would FMCSA regulations require the driver's employer to conduct a post-accident drug and alcohol test?

A test is required only if the damage to the commercial vehicle exceeds $10,000.
A test is required if any vehicle involved sustains disabling damage requiring it to be towed from the scene. (Correct answer)
A test is required regardless of damage or injury, as long as a citation was issued.
A test is required only if the driver requests one to clear their name.

Correct answer: A test is required if any vehicle involved sustains disabling damage requiring it to be towed from the scene.

According to FMCSA §382.303, in a non-fatal accident where the CMV driver receives a citation, post-accident testing is mandatory if either a person requires immediate medical treatment away from the scene, or one or more motor vehicles incurs disabling damage and must be towed.

Question 36: A CLP holder wants to transport hazardous materials. What is required?

No special requirement beyond the basic CLP
Just an H endorsement on their CLP
A written permit from the FMCSA
An H endorsement on their CLP and a CDL holder with H endorsement present (Correct answer)

Correct answer: An H endorsement on their CLP and a CDL holder with H endorsement present

To practice with hazmat, the CLP must carry the H endorsement and the accompanying CDL holder must also have the H endorsement.

Question 37: While driving, you encounter a situation that requires you to make a sudden stop. Your truck has anti-lock brakes (ABS). What is the correct way to use your brakes in this emergency?

Apply light, steady pressure to the brake pedal.
Slam on the brakes and turn the steering wheel sharply.
Brake as you normally would by applying firm, steady pressure. (Correct answer)
Pump the brake pedal rapidly to prevent the wheels from locking up.

Correct answer: Brake as you normally would by applying firm, steady pressure.

With an anti-lock braking system (ABS), you should brake as you normally would. Apply firm, steady pressure to the brake pedal. The ABS system will automatically prevent the wheels from locking up, allowing you to maintain steering control while braking. Pumping the brakes can interfere with the proper functioning of the ABS.

Question 38: How do antilock braking systems (ABS) affect air brake operation on commercial vehicles?

ABS reduces maximum air pressure to 80 psi to prevent skids on wet roads
ABS replaces the need for air brakes by using electronic actuators to stop the vehicle
ABS monitors wheel speed and modulates air pressure to prevent wheel lockup while keeping maximum braking force (Correct answer)
ABS allows the driver to steer while skidding by automatically applying opposite brakes

Correct answer: ABS monitors wheel speed and modulates air pressure to prevent wheel lockup while keeping maximum braking force

ABS sensors detect wheel lockup and automatically modulate brake pressure to restore rotation, helping drivers maintain steering control during hard stops.

Question 39: The sleeper berth split requires that the longer rest period spent in the berth be at least how many hours?

2 hours
5 hours
7 hours (Correct answer)
8 hours

Correct answer: 7 hours

Under the sleeper berth split, the longer segment must be at least 7 hours in the berth, combined with a separate minimum 3-hour off-duty period.

Question 40: Which statement about the Tanker Vehicles (N) endorsement knowledge test is accurate?

It only applies to vehicles carrying hazardous liquid cargo
It is combined with the HazMat test for all applicants
It covers liquid surge, stability, and safe driving techniques for tank vehicles (Correct answer)
It tests knowledge of tank vehicle maintenance intervals

Correct answer: It covers liquid surge, stability, and safe driving techniques for tank vehicles

The Tanker endorsement test focuses on the unique handling challenges of tank vehicles, including liquid surge and rollover risk.

Question 41: When a combination vehicle turns a corner, the rear wheels of the last trailer follow a different path than the front wheels of the tractor. This is called:

Yaw instability
Rearward amplification
Axle drift
Off-tracking (Correct answer)

Correct answer: Off-tracking

Off-tracking, or 'cheating,' is the term used to describe how the rear wheels of a vehicle or combination vehicle follow a path inside the path of the front wheels when turning. The longer the vehicle, the greater the amount of off-tracking.

Question 42: What is the legal BAC limit for CDL holders operating a commercial motor vehicle?

0.04% (Correct answer)
0.06%
0.08%
0.02%

Correct answer: 0.04%

The federal BAC limit for CDL holders operating a CMV is 0.04%, half the standard 0.08% limit for non-commercial drivers.

Question 43: Under the Entry-Level Driver Training (ELDT) regulations effective February 7, 2022, which group must complete theory and behind-the-wheel training from an FMCSA-registered provider?

Only drivers under 21 applying for a CDL
Drivers returning from a CDL disqualification of 1 year or more
Only drivers who previously failed a CDL skills test
Anyone applying for a new Class A or B CDL, upgrading their CDL class, or adding a school bus, passenger, or hazmat endorsement (Correct answer)

Correct answer: Anyone applying for a new Class A or B CDL, upgrading their CDL class, or adding a school bus, passenger, or hazmat endorsement

ELDT requires theory and BTW training from a registered provider for new CDL applicants (Class A or B) and those upgrading class or adding S, P, or H endorsements.

Question 44: When hauling a load that is 14 feet wide, what is required?

Only a slow-moving vehicle sign
Additional axles on the trailer
Special permits and possibly a pilot car or escort (Correct answer)
A pilot car only

Correct answer: Special permits and possibly a pilot car or escort

Loads exceeding legal width limits (typically 8.5 feet) require special permits and may require pilot cars or escorts depending on state regulations.

Question 45: In wet road conditions, the CDL manual recommends doubling your normal following distance. If your normal following distance is 6 seconds, you should increase it to at least how many seconds?

12 seconds (Correct answer)
10 seconds
7 seconds
8 seconds

Correct answer: 12 seconds

In wet or slippery conditions, you should double your following distance to maintain adequate stopping margin.

Question 46: Which of the following is a required entry on a driver's daily log?

Total miles driven that day (Correct answer)
Shipper's phone number
Co-driver's home address
Truck color and model year

Correct answer: Total miles driven that day

Total miles driven is a required entry on the daily log, along with date, carrier name, truck number, and co-driver name.

Question 47: What is the role of the S-cam in a drum air brake system?

It connects the air chamber push rod to the slack adjuster
It prevents the brakes from locking up during hard stops
It regulates the amount of air sent to each brake chamber
It rotates to force the brake shoes outward against the brake drum when brakes are applied (Correct answer)

Correct answer: It rotates to force the brake shoes outward against the brake drum when brakes are applied

When air pressure moves the push rod, it turns the S-cam, which pushes the brake shoes outward against the drum to create friction and slow the vehicle.

Question 48: A CDL holder convicted of a railroad-highway grade crossing violation will face a minimum disqualification of:

15 days for a first offense
60 days for a first offense (Correct answer)
30 days for a first offense
90 days for a first offense

Correct answer: 60 days for a first offense

A first railroad-highway grade crossing violation results in a minimum 60-day CDL disqualification.

Question 49: What happens to the emergency brakes on a trailer if the trailer breaks away from the tractor?

The trailer ABS system activates and brings it to a controlled stop
The trailer's spring brakes automatically apply due to the loss of air supply (Correct answer)
The trailer coasts freely until it comes to rest
Nothing — trailer brakes are controlled only from the cab

Correct answer: The trailer's spring brakes automatically apply due to the loss of air supply

When a trailer breaks away, the air supply line loses pressure, causing the trailer's spring brakes to automatically apply and stop the runaway trailer.

Question 50: Which of the following types of cargo REQUIRES special attention to prevent it from becoming a projectile hazard?

Individual metal pipes loaded on a flatbed (Correct answer)
Liquid cargo in a sealed tanker
Refrigerated goods in a reefer trailer
Bulk grain in a hopper trailer

Correct answer: Individual metal pipes loaded on a flatbed

Individual metal pipes on a flatbed can become dangerous projectiles if not properly secured with end-to-end blocking and adequate tie-downs on each pipe or bundle.

Question 51: What is the function of the brake chambers in an air brake system?

They convert air pressure into mechanical force to apply the brakes (Correct answer)
They store compressed air for emergency use
They filter moisture and contaminants from compressed air
They regulate the pressure sent to each individual wheel

Correct answer: They convert air pressure into mechanical force to apply the brakes

Brake chambers convert compressed air pressure into the mechanical force needed to push the brake shoes against the brake drums.

CDL Commercial Learner's Permit (CLP) Exam

The Commercial Learner's Permit (CLP) knowledge exam is administered by each state's Department of Motor Vehicles and is required before obtaining a Commercial Driver's License (CDL). It is based on the Federal Motor Carrier Safety Administration (FMCSA) CDL standards. The exam covers general knowledge, air brakes, combination vehicles, pre-trip inspection, cargo handling, hours of service, and adverse driving conditions. Passing score is typically 80%. Applicants must pass the relevant sections for their desired CDL class and endorsements.

Questions

90 min

Time Limit

80%

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