Kentucky General Knowledge CDL Practice Test
25 realistic General Knowledge practice questions for Kentucky CDL applicants. Required for: All CDL applicants (Class A, B, and C). Official test: 50 questions, 40 correct to pass.
Question 1 of 25 · Communication
When changing lanes you should:
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A.
Do it quickly so other drivers don't catch up
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B.
Signal early and check mirrors before and during the lane change
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C.
Turn off the radio
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D.
Speed up first
Correct answer: B.
Signal early, check mirrors, and look for traffic before and during the change.
Question 2 of 25 · Inspection
What is the most important reason for doing a vehicle inspection?
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A.
To meet DOT requirements
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B.
Safety for yourself and others
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C.
To save fuel
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D.
To avoid roadside inspections
Correct answer: B.
Safety is the most important reason. A defective vehicle puts you, your cargo, and others at risk.
Question 3 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 4 of 25 · Adverse Conditions
When you have to drive into the sun and visibility is reduced, what should you do?
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A.
Use sunglasses and lower the visor
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B.
Use only your high beams
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C.
Maintain your normal speed
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D.
Speed up to get past the area
Correct answer: A.
Use sunglasses and the visor and slow down. Reduced visibility increases stopping distance.
Question 5 of 25 · Emergency Maneuvers
Which of the following is a sign of tire failure?
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A.
A loud "bang" sound
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B.
Vibration or thumping
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C.
Heavy steering or fishtailing
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D.
All of the above
Correct answer: D.
A bang, vibration, heavy steering, or fishtailing can all indicate tire failure.
Question 6 of 25 · Driver Wellness
Which of the following is NOT a sign of fatigued driving?
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A.
Frequent yawning
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B.
Drifting from your lane
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C.
Rapid blinking and clear focus
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D.
Missing exits or traffic signs
Correct answer: C.
Rapid blinking with clear focus is not a fatigue sign. Yawning, drifting, and missing exits all are.
Question 7 of 25 · Speed Management
You are driving a vehicle that could safely be driven at 55 mph on an open highway. The traffic is heavy and moving at 35 mph. The safest speed for your vehicle in this traffic is most likely:
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A.
25 mph
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B.
35 mph
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C.
45 mph
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D.
55 mph
Correct answer: B.
You should generally adjust to the speed of surrounding traffic when it is safe to do so.
Question 8 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 9 of 25 · Mountain Driving
What may happen if you don't shift gears properly when going up a hill?
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A.
You will use less fuel
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B.
The transmission will be damaged
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C.
You may lose control on a downgrade
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D.
Engine RPM will be too low
Correct answer: C.
Improper gear use can result in losing control of speed, especially on the way back down a hill.
Question 10 of 25 · Emergency Maneuvers
Controlled braking is:
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A.
Pressing the brake to the floor and holding
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B.
Applying brakes hard enough to lock the wheels
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C.
Applying brakes to keep wheels just short of locking
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D.
Releasing brakes and coasting
Correct answer: C.
Controlled braking applies the brake firmly without locking the wheels, keeping the steering straight.
Question 11 of 25 · Speed Management
Whenever you double your speed, the impact in a crash is:
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A.
Doubled
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B.
The same
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C.
Four times greater
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D.
Half
Correct answer: C.
Crash energy increases with the square of speed — doubling speed quadruples crash forces.
Question 12 of 25 · Following Distance
Following distance for a heavy vehicle traveling below 40 mph should be at least:
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A.
1 second per 10 feet of vehicle length
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B.
Half the length of the vehicle
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C.
Two seconds total
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D.
No specific amount required
Correct answer: A.
Use one second of following distance for every 10 feet of vehicle length below 40 mph; add a second above 40 mph.
Question 13 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 14 of 25 · Adverse Conditions
What should you do before driving in fog?
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A.
Use high beams to see further
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B.
Slow down and use low beams and fog lights if equipped
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C.
Speed up to clear the fog area
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D.
Follow another vehicle closely
Correct answer: B.
Slow down before entering fog. Use low beams and any installed fog lights.
Question 15 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 16 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 17 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 18 of 25 · Driver Wellness
Distracted driving includes:
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A.
Talking on a hand-held cell phone
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B.
Eating
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C.
Reading maps
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D.
All of the above
Correct answer: D.
All of these activities take attention from driving and are forms of distracted driving.
Question 19 of 25 · Speed Management
When you double your speed, your stopping distance is multiplied by approximately:
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A.
Two
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B.
Three
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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 20 of 25 · Backing
Which of these statements about backing a heavy vehicle is true?
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A.
Back in a curved path whenever possible
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B.
Avoid backing whenever you can
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C.
Back as quickly as possible
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D.
Use only the right mirror
Correct answer: B.
Avoid backing whenever you can. Park where you will be able to pull forward to leave.
Question 21 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 22 of 25 · Driver Wellness
What should you do when an aggressive driver confronts you?
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A.
Make eye contact and respond
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B.
Try to escape the situation safely and avoid eye contact
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C.
Slow down to teach a lesson
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D.
Speed up and pass
Correct answer: B.
Avoid engagement, give space, do not make eye contact, and report the behavior.
Question 23 of 25 · Emergency Maneuvers
What should you do if your brakes fail on a downgrade?
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A.
Pump the brakes vigorously
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B.
Look for an escape ramp or open area to slow down
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C.
Shift into neutral
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D.
Turn off the engine
Correct answer: B.
If brakes fail, look for an escape ramp or a route that will slow your vehicle without endangering others.
Question 24 of 25 · ABS
ABS:
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A.
Allows you to drive faster
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B.
Lets you brake hard without losing steering control
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C.
Means you don't have to use safe driving techniques
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D.
Eliminates the need to inspect brakes
Correct answer: B.
ABS preserves steering during emergency braking but does not shorten stopping distance.
Question 25 of 25 · Inspection
Pre-trip inspection of the vehicle should be done in the same order each time so that you:
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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.
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 Kentucky Division of Driver Licensing administers this knowledge test as part of its commercial driver license program. To earn the CDL General Knowledge on your Kentucky CDL, you need to score at least 40 out of 50 on the official version.
Topics covered on this practice test
- Emergency Maneuvers: 3 questions
- Driver Wellness: 3 questions
- Speed Management: 3 questions
- Inspection: 2 questions
- Adverse Conditions: 2 questions
- CDL Rules: 2 questions
- Backing: 2 questions
- Communication: 1 question
- Night Driving: 1 question
- Cargo: 1 question
- Mountain Driving: 1 question
- Following Distance: 1 question
- Emergency Equipment: 1 question
- Rail Crossings: 1 question
- ABS: 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 Kentucky 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 Kentucky