Arizona General Knowledge CDL Practice Test
25 realistic General Knowledge practice questions for Arizona CDL applicants. Required for: All CDL applicants (Class A, B, and C). Official test: 50 questions, 40 correct to pass.
Question 1 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
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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 2 of 25 · Cargo
Which is correct about cargo and weight balance?
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A.
Heavy cargo should always be at the rear
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B.
Cargo should be balanced and secured to prevent shifting
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C.
Side-to-side balance does not matter
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D.
Top-heavy loads improve stability
Correct answer: B.
Cargo must be evenly balanced and well secured. Top-heavy loads increase rollover risk.
Question 3 of 25 · Emergency Maneuvers
Stab braking is used:
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A.
Only on slippery roads
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B.
When you must stop quickly with non-ABS brakes
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C.
Whenever you stop
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D.
Only on downgrades
Correct answer: B.
Stab braking is an emergency technique used with non-ABS brakes: apply brakes fully, release when wheels lock, then reapply.
Question 4 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 5 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 6 of 25 · Emergency Equipment
What three kinds of emergency equipment must you have in your vehicle?
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A.
Spare tire, fuses, and reflective triangles
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B.
Fire extinguisher, spare fuses (if equipped), and warning devices
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C.
First aid kit, water, and flares
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D.
Tool kit, fuel can, and flag
Correct answer: B.
You must have a fire extinguisher, spare electrical fuses (if equipped), and warning devices for stopped vehicles.
Question 7 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 8 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 9 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 10 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 11 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 12 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 13 of 25 · Inspection
What is the minimum tread depth for steering axle tires?
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A.
2/32 inch
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B.
4/32 inch
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C.
6/32 inch
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D.
8/32 inch
Correct answer: B.
Federal regulations require at least 4/32 inch tread depth on steering axle tires.
Question 14 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 15 of 25 · Inspection
Excessive heat in tires can:
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A.
Improve handling
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B.
Cause tire failure
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C.
Help fuel economy
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D.
Increase tire life
Correct answer: B.
Excessive heat causes blowouts and serious damage. Check for hot tires after driving.
Question 16 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 17 of 25 · Backing
You should always try to park:
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A.
So that you will have to back when leaving
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B.
So that you can pull forward when leaving
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C.
On the right shoulder of any highway
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D.
Without using the parking brake
Correct answer: B.
Park so that you can pull forward to leave. Backing should always be avoided when possible.
Question 18 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 19 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 20 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 21 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 22 of 25 · Speed Management
When you double your speed, your stopping distance is multiplied by approximately:
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A.
Two
-
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 23 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 24 of 25 · Inspection
When inspecting your vehicle, the engine should be:
-
A.
Running with the hood open
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B.
Off, with the parking brake set, before starting checks under the hood
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C.
Idling in gear
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D.
Warm but turned off only on hills
Correct answer: B.
Set the parking brake, turn off the engine, and chock the wheels before checking under the hood.
Question 25 of 25 · Basic Control
Convex (curved) mirrors:
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A.
Make objects appear larger and closer than they really are
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B.
Make objects appear smaller and farther away than they really are
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C.
Provide a normal view
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D.
Are required only on doubles
Correct answer: B.
Convex mirrors widen the field of view but make objects look smaller and farther away.
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 Arizona Motor Vehicle Division administers this knowledge test as part of its commercial driver license program. To earn the CDL General Knowledge on your Arizona CDL, you need to score at least 40 out of 50 on the official version.
Topics covered on this practice test
- Inspection: 6 questions
- Emergency Maneuvers: 3 questions
- Cargo: 2 questions
- Basic Control: 2 questions
- Emergency Equipment: 2 questions
- Speed Management: 2 questions
- CDL Rules: 2 questions
- Driver Wellness: 1 question
- Rail Crossings: 1 question
- Following Distance: 1 question
- Backing: 1 question
- Adverse Conditions: 1 question
- Night Driving: 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 Arizona 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 Arizona