Ohio General Knowledge CDL Practice Test
25 realistic General Knowledge practice questions for Ohio CDL applicants. Required for: All CDL applicants (Class A, B, and C). Official test: 50 questions, 40 correct to pass.
Question 1 of 25 · Inspection
Pre-trip inspection of the vehicle should be done in the same order each time so that you:
-
A.
Will look professional to other drivers
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B.
Will learn it well and not skip anything
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C.
Can finish faster
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D.
Pass the test more easily
Correct answer: B.
Following the same order helps prevent missed steps and builds reliable habits.
Question 2 of 25 · Basic Control
Where should the wheel chocks be placed?
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A.
Behind one tire
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B.
In front of and behind tires on the same axle
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C.
Only when on a hill
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D.
Both front and rear tires of the steer axle
Correct answer: B.
Place chocks both in front of and behind the wheels to prevent the vehicle from rolling either way.
Question 3 of 25 · CDL Rules
Refusing a chemical test for alcohol or drugs while operating a CMV will result in:
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A.
A warning
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B.
A 90-day suspension
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C.
CDL disqualification of at least one year
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D.
A simple fine
Correct answer: C.
Refusal is treated the same as testing positive — minimum one-year disqualification.
Question 4 of 25 · Mountain Driving
When driving down a long, steep downgrade, you should:
-
A.
Apply the brakes lightly to keep the speed down
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B.
Use a low gear and engine braking with intermittent braking
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C.
Coast in neutral
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D.
Press brakes continuously
Correct answer: B.
Use the appropriate low gear, rely on engine braking, and apply service brakes intermittently to control speed.
Question 5 of 25 · Cargo
How can you tell if your vehicle is overloaded?
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A.
It rides higher than normal
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B.
It handles differently from when properly loaded
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C.
It uses less fuel
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D.
It accelerates faster
Correct answer: B.
Overloaded vehicles handle poorly — they accelerate slower, take longer to stop, and are harder to steer.
Question 6 of 25 · Speed Management
When you double your speed, your stopping distance is multiplied by approximately:
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A.
Two
-
B.
Three
-
C.
Four
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D.
Six
Correct answer: C.
Stopping distance grows with the square of speed. Doubling speed roughly quadruples the distance needed to stop.
Question 7 of 25 · Hours of Service
How often must a driver complete a written record of duty status?
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A.
Every 8 hours
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B.
Every 12 hours
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C.
Every 24 hours
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D.
Once a week
Correct answer: C.
A daily record of duty status (logbook) must be completed each 24-hour period.
Question 8 of 25 · Night Driving
Which of these is true about driving at night?
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A.
You can see further than during the day
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B.
Your reaction time is faster at night
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C.
You should reduce your speed
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D.
High beams should always be used
Correct answer: C.
You see less and farther obstacles appear later at night. Slow down so you can stop within the area lit by your headlights.
Question 9 of 25 · Emergency Equipment
Most heavy vehicle fires are caused by:
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A.
Hot tires from low pressure or under-inflated duals
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B.
Cold weather
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C.
Engine cooling system
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D.
Exhaust pipes only
Correct answer: A.
Hot tires and brakes are leading causes. Inspect tires and brakes regularly to prevent fires.
Question 10 of 25 · Adverse Conditions
What should you do when your vehicle hydroplanes?
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A.
Brake hard immediately
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B.
Release the accelerator and push in the clutch
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C.
Steer sharply
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D.
Accelerate to regain control
Correct answer: B.
Release the accelerator and push in the clutch. Don't use the brakes — let the wheels regain traction.
Question 11 of 25 · Adverse Conditions
Hydroplaning is most likely to occur when:
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A.
Tires are properly inflated
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B.
Speed is below 30 mph
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C.
Roads are dry
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D.
Tires lose contact with the road on wet pavement
Correct answer: D.
Hydroplaning happens when water builds up between the tire and the road, causing loss of contact.
Question 12 of 25 · CDL Rules
Drivers convicted of driving a CMV without a valid CDL face:
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A.
No fines for the first offense
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B.
Civil penalties up to $5,000 and possible jail time
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C.
Only a warning
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D.
A 30-day driving restriction
Correct answer: B.
Driving without a valid CDL can lead to significant federal civil penalties and possible criminal penalties.
Question 13 of 25 · Driver Wellness
You should not eat or drink while driving because:
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A.
It is illegal in all states
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B.
Spills can distract you
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C.
You should not put both hands on the wheel
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D.
It might damage the vehicle
Correct answer: B.
Eating and drinking divert attention and create spill hazards.
Question 14 of 25 · Communication
When should you check your mirrors?
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A.
Only before changing lanes
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B.
Frequently, to know what is around your vehicle
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C.
When parking only
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D.
Only at intersections
Correct answer: B.
Check mirrors regularly to know what is happening around your vehicle.
Question 15 of 25 · Inspection
When checking the engine compartment, your vehicle should be:
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A.
Idling in neutral
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B.
On a slight incline
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C.
Parked on level ground with the parking brake set and wheels chocked
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D.
Running with the parking brake off
Correct answer: C.
Always inspect the engine compartment with the vehicle parked on level ground, parking brake set, and wheels chocked.
Question 16 of 25 · Cargo
Which is true about cargo securement?
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A.
Drivers are responsible for inspecting cargo
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B.
Cargo only needs to be inspected at the start of a trip
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C.
Securement is the shipper's sole responsibility
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D.
Once strapped, cargo never needs re-checking
Correct answer: A.
Drivers must inspect cargo and its securement at the start of the trip and re-check periodically.
Question 17 of 25 · Night Driving
When meeting an oncoming vehicle at night, you should:
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A.
Look directly at the headlights
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B.
Look toward the right side of the road
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C.
Switch to high beams
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D.
Increase speed
Correct answer: B.
Look toward the right side of the road to avoid being blinded by oncoming headlights.
Question 18 of 25 · CDL Rules
Driving with a BAC of 0.04 or higher in a CMV will result in:
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A.
A warning
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B.
A 30-day suspension
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C.
A CDL disqualification of at least one year
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D.
No penalty if off-duty
Correct answer: C.
A first offense disqualifies you for at least one year (three years if hauling hazardous materials).
Question 19 of 25 · ABS
What does ABS do?
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A.
Helps you stop faster
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B.
Prevents wheels from locking up during hard braking
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C.
Replaces engine brakes
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D.
Eliminates the need for service brakes
Correct answer: B.
Antilock braking systems prevent wheel lockup, helping you maintain steering control during hard braking.
Question 20 of 25 · Speed Management
Engine brakes (Jakes) should not be used:
-
A.
On dry pavement at highway speed
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B.
On slippery roads while loaded or empty
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C.
When descending a steep grade
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D.
Heading toward a long downhill
Correct answer: B.
Avoid engine brakes on slippery roads — they can cause the drive wheels to lose traction.
Question 21 of 25 · Backing
The most important hand signal you and a helper should agree on is:
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A.
Speed up
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B.
Stop
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C.
Turn left
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D.
Back straight
Correct answer: B.
Always agree on a clear stop signal before backing. The helper must be able to stop you instantly.
Question 22 of 25 · Emergency Equipment
When stopped on the side of a level, straight, two-lane road, where should the three reflective triangles be placed?
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A.
10, 50, and 100 feet behind the vehicle
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B.
10, 100, and 200 feet behind the vehicle
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C.
On the front, side, and rear of the vehicle
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D.
50, 100, and 200 feet on the traffic side
Correct answer: B.
Triangles go 10, 100, and 200 feet behind the vehicle on a straight, level, two-lane road.
Question 23 of 25 · Testing
The road test will be scored on:
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A.
How fast you complete the route
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B.
Vehicle inspection, basic control, and on-road driving
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C.
Whether you wear a uniform
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D.
Your appearance
Correct answer: B.
You'll be evaluated on inspection skills, basic control skills, and safe on-road driving performance.
Question 24 of 25 · Rail Crossings
When approaching a railroad crossing without flashing lights or gates, you should:
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A.
Slow down, look, and listen for trains
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B.
Always come to a complete stop
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C.
Speed up to clear the crossing quickly
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D.
Sound horn but maintain speed
Correct answer: A.
Without active warning devices, slow down and look and listen carefully for an approaching train.
Question 25 of 25 · Inspection
The proper way to test the service brake on a vehicle is to:
-
A.
Pump the pedal three times
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B.
Push the brake pedal firmly while moving about 5 mph
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C.
Put the parking brake on
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D.
Listen for air leaks
Correct answer: B.
Move the vehicle forward at about 5 mph and apply the brake firmly. The vehicle should not pull to either side.
About the General Knowledge Test
The General Knowledge test covers safe vehicle inspection, basic vehicle control, shifting gears, communicating, controlling speed, controlling distance, seeing hazards, distracted driving, aggressive drivers, communicating with other drivers, night driving, driving in fog, winter driving, hot weather driving, mountain driving, driving emergencies, anti-lock braking systems, skid recovery, accident procedures, fires, alcohol and other drugs, hazardous materials awareness, and staying alert and fit to drive. Every commercial driver in the United States must pass this test before any other CDL endorsement can be added.
The Ohio Bureau of Motor Vehicles administers this knowledge test as part of its commercial driver license program. To earn the CDL General Knowledge on your Ohio CDL, you need to score at least 40 out of 50 on the official version.
Topics covered on this practice test
- Inspection: 3 questions
- CDL Rules: 3 questions
- Cargo: 2 questions
- Speed Management: 2 questions
- Night Driving: 2 questions
- Emergency Equipment: 2 questions
- Adverse Conditions: 2 questions
- Basic Control: 1 question
- Mountain Driving: 1 question
- Hours of Service: 1 question
- Driver Wellness: 1 question
- Communication: 1 question
- ABS: 1 question
- Backing: 1 question
- Testing: 1 question
- Rail Crossings: 1 question
How to use this practice test
- Read each question carefully. CDL questions are written precisely — small wording differences matter.
- Click "Show Answers & Explanations" only after answering every question. Don't peek mid-test.
- Read the explanation for every question, even ones you got right. The reasoning is more important than the answer.
- Repeat the test until you score 100%. The questions are deterministic per state, so you can track your improvement over multiple sessions.
- Move on to the other endorsement tests for Ohio until you're ready for the official exam.
Tips specific to the General Knowledge test
The General Knowledge test is the foundation of every CDL. Topics include vehicle inspection, basic control, shifting, communicating, controlling speed, controlling space, hazard perception, distracted driving, night driving, fog, winter, hot weather, mountain driving, emergencies, anti-lock brakes, skid recovery, accident procedures, fires, alcohol, hazardous materials awareness, and staying alert. Most failures come from speeding through inspection-related questions; slow down and read carefully.
Other practice tests for Ohio