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200+ Free CDL Practice Questions

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What is the first step in the seven-step pre-trip inspection method?

A
B
C
D
to track
2026 Statistics

Key Facts: CDL Exam

80%

Federal Passing Threshold

49 CFR 383.133

30+

Federal Minimum Item Count

49 CFR 383.133 / 383.111

Feb 7, 2022

ELDT Effective Date

FMCSA ELDT rule

State-issued

License Authority

State DMV agencies under FMCSA standards

$10-125

Typical Knowledge-Test Fee

Varies by state

50 (common)

General Knowledge Form Length

Common state CDL manual format

Federal CDL knowledge standards require at least 30 questions for basic knowledge testing with an 80% minimum passing score (49 CFR 383.133). States administer the exam and commonly use longer General Knowledge forms (often 50 questions). FMCSA's ELDT rule became effective February 7, 2022 and remains a core prerequisite for first-time Class A/Class B, and first-time P/S/H endorsement applicants.

Sample CDL Practice Questions

Try these sample questions to test your CDL exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 200+ question experience with AI tutoring.

1What is the first step in the seven-step pre-trip inspection method?
A.Approach the vehicle and check its general condition
B.Check under the hood
C.Start the engine and inspect inside the cab
D.Walk around and inspect the entire vehicle
Explanation: The first step of the seven-step pre-trip inspection is to approach the vehicle and look at its general condition. This includes checking for damage, whether the vehicle is leaning to one side, and looking under the vehicle for fresh leaks of oil, coolant, grease, or fuel. This initial overview can immediately reveal serious problems before you invest time in a detailed inspection.
2During a pre-trip inspection, what should you check in the engine compartment?
A.Only the oil level
B.Oil level, coolant level, power steering fluid, belts, and hoses
C.Only the coolant level and belts
D.Only items visible without opening any caps
Explanation: A thorough engine compartment inspection includes checking the oil level, coolant level in the radiator, power steering fluid, condition of belts and hoses for wear or cracks, and looking for leaks. You should also check the alternator, water pump, air compressor, and any other belt-driven components. Checking only one or two items could mean missing a critical problem that leads to a breakdown or safety hazard on the road.
3When performing a pre-trip inspection, the driver should ensure that the steering wheel free play (lash) does not exceed what limit?
A.5 degrees in either direction
B.10 degrees in either direction (approximately 2 inches on a 20-inch wheel)
C.15 degrees in either direction
D.20 degrees in either direction
Explanation: Federal Motor Carrier Safety Regulations require that steering wheel free play (lash) not exceed 10 degrees in either direction, which translates to roughly 2 inches of movement on a 20-inch diameter steering wheel before the front wheels begin to turn. Excessive free play indicates worn steering components and can make precise steering difficult, especially in emergency maneuvers. A vehicle with excessive steering lash would be placed out of service.
4During the cab check portion of a pre-trip inspection, you should test the parking brake by:
A.Driving forward slowly and applying the parking brake
B.Putting the vehicle in gear with the parking brake set and gently pressing the accelerator to see if the vehicle holds
C.Visually checking that the parking brake handle is in the correct position
D.Checking the parking brake cable under the vehicle
Explanation: To properly test the parking brake, set the parking brake, put the vehicle in a low gear, and gently press the accelerator to see if the brake holds the vehicle in place. This functional test confirms the parking brake can actually prevent the vehicle from moving, which is essential for safety when parked on grades. A visual check alone is insufficient because it does not verify that the brake mechanism is actually functioning properly.
5Which emergency equipment is required to be on a commercial motor vehicle?
A.Fire extinguisher, spare fuses, and three red reflective triangles
B.First aid kit, fire extinguisher, and flares only
C.Fire extinguisher and road flares only
D.Spare tire, jack, and reflective vest
Explanation: Federal regulations require every commercial motor vehicle to carry a properly charged and rated fire extinguisher (minimum 5 B:C rating, or two 4 B:C extinguishers), spare electrical fuses (unless the vehicle has circuit breakers), and three red reflective warning triangles (or equivalent). These items are checked during inspections and roadside enforcement stops. A vehicle missing any of these required items can be cited for a violation.
6A post-trip inspection report is important because:
A.It is only required for vehicles carrying hazardous materials
B.It alerts the carrier to vehicle defects that may need repair before the vehicle is driven again
C.It replaces the need for the next driver to do a pre-trip inspection
D.It is optional but recommended by the FMCSA
Explanation: The post-trip inspection report (also called a DVIR, or Driver Vehicle Inspection Report) is required by FMCSA regulations (49 CFR 396.11). Its purpose is to document any defects or deficiencies discovered at the end of the trip so the carrier can arrange repairs before the vehicle is dispatched again. The next driver must review the previous post-trip report and verify that any noted defects have been repaired or certified as not needing repair. It does not replace the next driver's pre-trip inspection obligation.
7During a pre-trip inspection, the driver notices a coolant leak near the water pump. What should the driver do?
A.Note it on the report and drive carefully to the next service stop
B.Add more coolant and continue the trip
C.Do not drive the vehicle until the leak is repaired
D.Drive only short distances and monitor the temperature gauge
Explanation: A coolant leak is a serious defect that can lead to engine overheating and catastrophic engine failure. The vehicle should not be driven until the leak is repaired. Driving with a coolant leak risks engine damage, potential fire (if coolant contacts hot exhaust components), and could result in a roadside breakdown in an unsafe location. FMCSA regulations require that defects affecting safe operation be corrected before the vehicle is driven.
8Which of the following is an out-of-service condition that would prevent a vehicle from being driven?
A.A small crack in the windshield that does not obstruct the driver's view
B.A missing mud flap on a rear wheel
C.Brake lining thickness below the minimum allowed by regulations
D.A broken antenna on the CB radio
Explanation: Brake lining worn below the minimum thickness specified in FMCSA out-of-service criteria is a critical safety defect. The North American Standard Out-of-Service Criteria lists specific thresholds: brake lining must not be less than 1/4 inch thick at the thinnest point for air-braked vehicles. When brake linings are too thin, braking effectiveness is severely compromised, and the vehicle must be placed out of service until repairs are made. A small windshield crack not in the driver's view, a missing mud flap, or a broken CB antenna are defects but not typically out-of-service conditions.
9During the pre-trip inspection, which of the following should a driver check regarding the exhaust system?
A.Only that the muffler is present
B.That the exhaust system is secure, not leaking, and not in contact with fuel lines, wiring, or air lines
C.Only that exhaust fumes are not entering the cab
D.That the catalytic converter is functioning properly by checking emissions color
Explanation: When inspecting the exhaust system, the driver should verify that all components are properly mounted and secured, there are no leaks (which could allow poisonous carbon monoxide to enter the cab), and the exhaust system is not in contact with fuel supply lines, wiring, or air brake lines. Heat from the exhaust can damage these components, potentially causing fuel leaks, electrical fires, or brake failures. A complete exhaust system inspection goes beyond just checking for the presence of a muffler.
10What is the minimum tread depth required for steer axle tires on a commercial motor vehicle?
A.2/32 of an inch
B.4/32 of an inch
C.6/32 of an inch
D.1/32 of an inch
Explanation: Federal regulations require steer axle tires to have a minimum tread depth of 4/32 of an inch (approximately 3.2 mm) in every major groove. Steer tires have a higher minimum than other axle positions (which require only 2/32 of an inch) because the steer tires are critical for directional control of the vehicle. Tires below this minimum are considered unsafe and will result in a violation or out-of-service order during an inspection.

About the CDL Exam

The CDL General Knowledge exam is required for commercial driver licensing and is administered by each state under federal standards. Federal rules require an 80% passing score and set a minimum item count for core knowledge testing. FMCSA's ELDT rule (effective February 7, 2022) applies to first-time Class A/Class B applicants, school bus, passenger, and hazmat endorsements.

Questions

50 scored questions

Time Limit

60 minutes

Passing Score

80%

Exam Fee

$10-125 (State DMV / FMCSA)

CDL Exam Content Outline

~20%

Vehicle Inspection & Safety

Pre-trip/post-trip inspections, brakes, tires, lights, mirrors, emergency equipment

~20%

Vehicle Control & Operation

Basic control, gear shifting, backing, maneuvering, speed management

~25%

Safe Driving Practices

Hazard perception, space management, night/weather driving, emergency procedures

~15%

Cargo & Load Management

Cargo securement, weight limits, loading/unloading, inspection schedules

~20%

Rules & Regulations

FMCSA regulations, CDL licensing, hours of service, hazmat basics, air brake fundamentals

How to Pass the CDL Exam

What You Need to Know

  • Passing score: 80%
  • Exam length: 50 questions
  • Time limit: 60 minutes
  • Exam fee: $10-125

Keys to Passing

  • Complete 500+ practice questions
  • Score 80%+ consistently before scheduling
  • Focus on highest-weighted sections
  • Use our AI tutor for tough concepts

CDL Study Tips from Top Performers

1Master pre-trip inspection procedures — know the seven-step inspection method and what to check at each step
2Learn stopping distances: perception distance + reaction distance + braking distance = total stopping distance
3Memorize cargo securement rules: inspect within first 50 miles, then every 3 hours or 150 miles
4Study air brake components and testing procedures — the air brake endorsement removal requires specific knowledge
5Know hours of service rules: 11-hour driving limit, 14-hour on-duty limit, 30-minute break requirement, 60/70-hour limit
6Understand hazmat placarding: when placards are required, the nine hazard classes, and shipping paper locations

Frequently Asked Questions

How many questions are on the CDL General Knowledge test?

Under federal standards, the basic knowledge test must include at least 30 questions and requires 80% to pass. Many states use longer General Knowledge forms (commonly 50 questions), so check your state CDL manual for the exact count.

What is ELDT and do I need it for a CDL?

Entry-Level Driver Training (ELDT) is required by FMCSA for anyone obtaining a Commercial Learner's Permit (CLP) on or after February 7, 2022. ELDT includes theory instruction, behind-the-wheel road training, and range/backing practice. Training must be completed through an FMCSA-registered Training Provider (TPR). Drivers with CDLs issued before this date are exempt.

What CDL endorsements are available?

Common CDL endorsements include H (Hazmat), N (Tank Vehicle), P (Passenger), S (School Bus), and T (Double/Triple Trailers), plus air-brake and combination-vehicle knowledge testing where applicable. Endorsement availability and item counts are set by each state under federal standards.

How much does a CDL cost?

CDL costs vary by state. The knowledge test fee ranges from $10-125. Total CDL costs including all tests, licensing, and fees range from $200-450. ELDT training programs range from $3,000-12,000+ for full CDL training schools, though some trucking companies offer sponsored training.

Who writes and administers the CDL test?

FMCSA sets the federal standards, but each state DMV or licensing agency administers CDL knowledge and skills testing. That means exact test length, retake policy, and fee schedule can vary by state.