Wisconsin General Knowledge CDL Practice Test
25 realistic General Knowledge practice questions for Wisconsin 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
When should you stop and check your tires after starting a long trip?
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A.
After 250 miles
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B.
Within the first 50 miles, then every 150 miles or 3 hours
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C.
Only when you stop for fuel
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D.
Tires don't need to be checked once you're moving
Correct answer: B.
Stop after the first 50 miles to check tires, then re-check every 150 miles or three hours.
Question 2 of 25 · Hazard Awareness
How can you tell if your truck or bus has a hazardous materials shipment?
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A.
It is moving slowly
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B.
Diamond-shaped placards are displayed
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C.
A flashing yellow light is on
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D.
It is following another truck
Correct answer: B.
Diamond-shaped placards on the vehicle indicate the presence of hazardous materials.
Question 3 of 25 · Cargo
When it comes to cargo, which is true?
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A.
You can rely on the shipper to ensure secure load
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B.
You are responsible for confirming the cargo is properly distributed and secured
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C.
Securement is verified at weigh stations only
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D.
Once on the road, no further inspection is necessary
Correct answer: B.
You are responsible. Inspect within 50 miles and at every change of duty status, and at least every 150 miles or 3 hours.
Question 4 of 25 · Adverse Conditions
Black ice is:
-
A.
A thick layer of ice that is easily seen
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B.
A thin layer that looks wet pavement
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C.
Only found in the far north
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D.
Not a real road hazard
Correct answer: B.
Black ice is a thin, transparent layer that looks like wet pavement. It is extremely dangerous.
Question 5 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 6 of 25 · Adverse Conditions
When a vehicle hydroplanes, the brakes:
-
A.
Will work better than usual
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B.
May cause the vehicle to spin
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C.
Should be applied hard
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D.
Cause the engine to stall
Correct answer: B.
Braking on a hydroplaning surface can lock wheels and cause spins. Ease off the throttle instead.
Question 7 of 25 · CDL Rules
What is the legal blood alcohol concentration (BAC) limit for CDL drivers?
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A.
0.08%
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B.
0.05%
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C.
0.04%
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D.
0.02%
Correct answer: C.
Federal CDL law sets the BAC limit at 0.04%, half the limit for non-commercial drivers.
Question 8 of 25 · Basic Control
Which of these is the proper way to hold a steering wheel?
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A.
One hand at 12 o'clock
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B.
Both hands on opposite sides of the wheel
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C.
Both hands on top
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D.
One hand at 6 o'clock
Correct answer: B.
Hold the wheel firmly with both hands placed on opposite sides for full control.
Question 9 of 25 · Inspection
What is the minimum tread depth for non-steering axle tires?
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A.
1/32 inch
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B.
2/32 inch
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C.
4/32 inch
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D.
6/32 inch
Correct answer: B.
Federal regulations require at least 2/32 inch on non-steering tires.
Question 10 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 11 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 12 of 25 · Inspection
The proper way to test the service brake on a vehicle is to:
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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.
Question 13 of 25 · Driver Wellness
Aggressive drivers should be:
-
A.
Confronted
-
B.
Reported and given plenty of room
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C.
Followed closely
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D.
Passed quickly without signaling
Correct answer: B.
Stay clear of aggressive drivers and report dangerous behavior to authorities.
Question 14 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 15 of 25 · Speed Management
The total stopping distance of a CDL vehicle includes:
-
A.
Perception, reaction, and braking distance
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B.
Only braking distance
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C.
Following distance and brake lag
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D.
Only the distance traveled while braking
Correct answer: A.
Total stopping distance is the sum of perception distance, reaction distance, brake lag, and braking distance.
Question 16 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 17 of 25 · Inspection
Mirror adjustment should be checked:
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A.
Only at the start of the trip
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B.
Only when something seems wrong
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C.
Prior to the start of any trip and can only be checked accurately when the trailer(s) are straight
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D.
Once per week
Correct answer: C.
Adjust and check mirrors before each trip while the trailers are straight.
Question 18 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 19 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 20 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 21 of 25 · Speed Management
Engine retarders should be turned off when:
-
A.
Driving uphill
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B.
The road is wet, icy, or snow covered
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C.
Traffic is heavy
-
D.
You are loaded
Correct answer: B.
Retarders can cause drive wheels to skid on slippery surfaces. Turn them off in poor traction conditions.
Question 22 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 23 of 25 · Driver Wellness
Which of these statements about staying alert to drive is true?
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A.
Coffee will overcome fatigue
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B.
You can rely on caffeine to stay awake
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C.
There is no substitute for sleep
-
D.
Cold air will keep you alert all night
Correct answer: C.
There is no substitute for adequate rest. Caffeine and cold air provide only temporary alertness.
Question 24 of 25 · Adverse Conditions
Which of the following is true about driving in fog?
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A.
You should always drive with high beams
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B.
Avoid driving in fog if possible
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C.
Use the right edge of the road as a guide rather than the center line
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D.
Both b and c
Correct answer: D.
Avoid driving in fog when possible. If unavoidable, use low beams and the right edge as a guide.
Question 25 of 25 · Emergency Maneuvers
Which of the following is a sign of tire failure?
-
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.
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 Wisconsin Division of Motor Vehicles administers this knowledge test as part of its commercial driver license program. To earn the CDL General Knowledge on your Wisconsin CDL, you need to score at least 40 out of 50 on the official version.
Topics covered on this practice test
- Inspection: 5 questions
- Adverse Conditions: 4 questions
- CDL Rules: 4 questions
- Driver Wellness: 3 questions
- Basic Control: 2 questions
- Speed Management: 2 questions
- Hazard Awareness: 1 question
- Cargo: 1 question
- Testing: 1 question
- Hours of Service: 1 question
- Emergency Maneuvers: 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 Wisconsin 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 Wisconsin