MINNESOTA COMMERCIAL DRIVER LICENSE KNOWLEDGE – CLASS B EXAM PRACTICE 2026/2027 COMPLETE (50) CURRENT TESTING QUESTIONS AND CORRECT ANSWERS WITH DETAILED RATIONALES.

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MINNESOTA COMMERCIAL DRIVER LICENSE
KNOWLEDGE – CLASS B EXAM PRACTICE 2026/2027
COMPLETE (50) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED RATIONALES.
DRIVER
Prepare effectively for the Minnesota Commercial Driver License Knowledge – Class B
Exam with this focused practice resource. It supports review of Class B CDL
regulations, vehicle operation, safety procedures, inspections, air brakes, and
commercial driving requirements. Use the material to reinforce your knowledge,
practice key concepts, and identify areas that may require additional study. This
resource is suited for aspiring Class B commercial drivers, CDL applicants,
professional drivers, and candidates preparing for the Minnesota Class B CDL
knowledge examination.



Multiple choice.
SECTION 1: GENERAL KNOWLEDGE – SAFE DRIVING & VEHICLE
OPERATION (Questions 1–30)
Question #1
You may not consume alcohol within ____ of going on duty.
A. 2 hours
B. 4 hours
C. 6 hours
D. 8 hours
Correct Answer: B
Rationale: Alcohol consumption within 4 hours of going on duty is
prohibited for commercial drivers. This federal regulation ensures drivers
are not under the influence when operating a commercial motor vehicle.

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Question #2
When you brake a vehicle that has ABS (Anti-Lock Braking System), you
should:
A. Pump the brakes rapidly
B. Use only the braking force necessary to stop safely and stay in control
C. Apply maximum pressure and hold
D. Release the brakes immediately
Correct Answer: B
Rationale: With ABS, you should apply steady, firm pressure and let the
system do its job. Do not pump the brakes; pump only if ABS is not working.
Stay in control and use only the braking force necessary to stop safely.


Question #3
In winter, during your pre-trip inspection, you should check very thoroughly
the:
A. Defrosting and heating equipment
B. Coolant level and antifreeze amount
C. Your tires
D. Wipers and washers
E. All of the listed answers
Correct Answer: E
Rationale: Winter pre-trip inspections require checking all critical
systems: defrosting/heating equipment, coolant/antifreeze levels, tires, and
wipers/washers. Cold weather can compromise all these systems, making
thorough inspection essential.


Question #4
What is the minimum tire tread depth for the steering axle of a commercial
vehicle?
A. 2/32 inch
B. 4/32 inch

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C. 6/32 inch
D. 8/32 inch
Correct Answer: B
Rationale: The minimum tread depth for steering axle tires is 4/32 inch.
For all other tires, the minimum is 2/32 inch. This provides adequate traction
for steering control.


Question #5
A Commercial Driver's License (CDL) is required to operate a vehicle with a
Gross Vehicle Weight Rating (GVWR) of:
A. 10,001 lbs or more
B. 16,001 lbs or more
C. 26,001 lbs or more
D. 50,000 lbs or more
Correct Answer: C
Rationale: A CDL is required for any vehicle with a GVWR of 26,001 pounds
or more. Class B specifically covers single vehicles at or above this weight,
with towing limited to trailers under 10,000 lbs.


Question #6
When driving a commercial vehicle, you should look ahead:
A. 5-10 seconds
B. 12-15 seconds
C. 20-30 seconds
D. 1 minute
Correct Answer: B
Rationale: Commercial drivers should look ahead 12-15 seconds to
identify hazards early and allow sufficient time to react. This is a critical
defensive driving technique.