Commercial Driver Licensure Exam

Commercial Driver Licensure Exam Practice Test Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of a pre-trip inspection?
• To check tire pressure only
• To ensure vehicle safety and compliance
• To practice driving skills
• To measure fuel efficiency
• To ensure vehicle safety and compliance

Rationale: A pre-trip inspection ensures the vehicle is safe to operate

and meets regulatory requirements.

• What is the correct hand signal for a left turn?
• Left arm extended straight out 1 / 4

• Left arm bent upward
• Left arm bent downward
• Right arm extended straight out
• Left arm extended straight out

Rationale: Extending the left arm straight out indicates a left turn

according to standard hand signals.

3. When driving a commercial vehicle, you should check mirrors:

• Only when changing lanes
• Frequently and before every maneuver
• Only on highways
• Once at the start of a trip
• Frequently and before every maneuver

Rationale: Checking mirrors often helps monitor blind spots and

surrounding traffic for safe operation.

• What is the maximum allowable blood alcohol concentration (BAC) for

commercial drivers?

A. 0.10%

B. 0.08%

C. 0.04%

D. 0.02%

C. 0.04%

Rationale: Federal regulations limit commercial drivers to a BAC of

0.04% to reduce risk of accidents. 2 / 4

• Which document must a commercial driver carry at all times while

operating a vehicle?

• Vehicle registration only
• Driver’s license only
• Driver’s license, medical certificate, and vehicle registration
• Insurance card only
• Driver’s license, medical certificate, and vehicle registration

Rationale: All three documents are required to legally operate a

commercial vehicle.

• How often should a commercial vehicle’s brakes be inspected?
• Every year
• Before each trip
• Once a month
• Only when problems occur
• Before each trip

Rationale: Pre-trip brake inspections ensure the braking system

functions safely and prevents accidents.

• What is the primary purpose of the “No-Zone”?
• To mark parking spaces
• To indicate blind spots around trucks
• To designate loading zones
• To signal emergency lanes
• To indicate blind spots around trucks 3 / 4

Rationale: No-Zones are areas around trucks where smaller vehicles

disappear from the driver’s view, increasing collision risk.

• When must a commercial driver use turn signals?
• Only on highways
• Only during lane changes
• At all times when changing lanes or turning
• Only in urban areas
• At all times when changing lanes or turning

Rationale: Turn signals communicate intentions to other road users,

reducing accidents.

• What is the safe following distance for a commercial vehicle under

normal conditions?

• 1 second
• 2 seconds
• 4 seconds
• 10 seconds
• 4 seconds

Rationale: A 4-second following distance allows adequate stopping

time for large commercial vehicles.

• What is the first action a driver should take if the brakes fail

while driving?

• Shift to a lower gear and apply the parking brake gradually
• Immediately steer off the road
• / 4