Missouri CDL General Knowledge Test (MO) 5

4.9 out of 5 (71 votes)
80% Passing score
50 Questions
10 Mistakes allowed
As a Missouri resident gearing up for your CDL general knowledge test, you've come to the right place. This is your essential fifth Missouri CDL practice test, a crucial step in preparing for the DMV's Commercial Driver's License examination. Our practice permit test offers a realistic experience with 50 permit test questions and answers, mirroring the actual test format. To pass, you'll need to correctly answer at least 40 questions. What makes our CDL practice test special is its focus on Missouri-specific content. We understand that driving laws and regulations can vary significantly from state to state. That's why our questions are meticulously designed to reflect Missouri's unique driving conditions, road signs, and rules. The question pool is expansive and diverse, ensuring that each practice session covers a broad spectrum of topics. This variety is vital in preparing you comprehensively for what you'll face at the DMV during the real Missouri CDL general knowledge test in 2026. From safety regulations to vehicle operation, each question is a step towards ensuring you're fully prepared for your CDL permit test. We source our questions directly from the official Missouri CDL driver's manual - the same source used for the actual DMV written test. This alignment with the state-managed manual guarantees that our CDL general knowledge practice test is as relevant and up-to-date as possible. Repeated practice is key to success, and with our Missouri CDL practice test, you can retake it as many times as you need. The questions will remain consistent across attempts, allowing you to gauge your progress and understanding effectively. Remember, if it's not in the Missouri CDL manual, it won't appear on your permit test or our sample quizzes. By focusing your study efforts with our Missouri CDL general knowledge practice test, you're not just preparing for an exam - you're becoming a safer, more knowledgeable driver on Missouri roads!
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Sample Missouri CDL Test Questions - General Knowledge

Question 1

What is the main safety reason for shifting a commercial vehicle into the proper gear?

  1. A It keeps the engine at one constant temperature
  2. B It prevents the radiator from losing coolant
  3. C It increases oil circulation through the crankcase
  4. D It helps the driver maintain vehicle control

Correct answer: D – It helps the driver maintain vehicle control

Correct gear selection is important for maintaining control of a commercial vehicle. If you cannot place the transmission in the appropriate gear while driving, you will have less control. Drivers should learn the proper shifting method and operating ranges for the vehicle they use.

Source: Missouri Commercial Driver License Manual — § 2.3, “Shifting Gears”

Question 2

Which two air lines are found on every air-braked combination vehicle?

  1. A Service and emergency
  2. B Service and brake
  3. C Brake and emergency
  4. D Pressure and brake

Correct answer: A – Service and emergency

Every combination vehicle has a service line and an emergency line, which is also called the supply line. The service line carries the signal that controls trailer service-brake application. The emergency line supplies air to the trailer tanks and is connected with the trailer's emergency-brake operation.

Source: Missouri Commercial Driver License Manual — § 6.2.4, “Trailer Air Lines”

Question 3

On a Missouri roadway, what does a LOOSE GRAVEL warning sign indicate?

This sign alerts the driver of __________.
  1. A A road-construction zone begins ahead
  2. B Slow-moving traffic is ahead
  3. C The roadway is slippery only when wet
  4. D Loose gravel or stones may cover the roadway surface

Correct answer: D – Loose gravel or stones may cover the roadway surface

The LOOSE GRAVEL sign warns that loose gravel may be present on the roadway surface. It is a specific surface-condition warning, not a general construction, slow-traffic, or slippery-when-wet sign. Drivers should identify the particular condition shown when selecting an appropriate response.

Source: Manual on Uniform Traffic Control Devices for Streets and Highways, 11th ed., Rev. 1 — § 2C.30, “Surface Condition Signs (W8-5, W8-7, W8-8, W8-11, W8-13, and W8-14)”

Question 4

If your commercial vehicle catches fire in Missouri, should you pull into a service station because firefighting equipment may be available?

  1. A True
  2. B False

Correct answer: B – False

If a vehicle catches fire, get it off the road and stop in an open area away from buildings, vegetation, other vehicles, and anything else that could ignite. Do not pull into a service station. Notify emergency services and provide your location as soon as possible.

Source: Missouri Commercial Driver License Manual — § 2.21.3, “Fire Fighting”

Question 5

What is the primary safety benefit of an antilock braking system?

  1. A It permits higher speeds and shorter following distances
  2. B It prevents every type of turning skid
  3. C It always reduces stopping distance
  4. D It helps prevent wheel lockup and maintain control during braking

Correct answer: D – It helps prevent wheel lockup and maintain control during braking

ABS helps keep wheels from locking during hard braking, allowing the driver to retain more control. It may help the driver steer around an obstacle and avoid skids caused by overbraking. ABS does not necessarily shorten stopping distance and cannot compensate for unsafe speed, poor brakes, or careless driving.

Source: Missouri Commercial Driver License Manual — §§ 2.18.4, “How ABS Helps You,” and 2.18.8, “Safety Reminders”

Question 6

Can underinflated tires contribute to a commercial-vehicle fire?

  1. A True
  2. B False

Correct answer: A – True

Underinflated tires are specifically identified as a cause of vehicle fires, along with dual tires that touch. Too little air pressure is also a tire defect that should be detected during inspection. Drivers should check their tires during the trip for signs of excessive heat.

Source: Missouri Commercial Driver License Manual — §§ 2.1.3, “What to Look For,” and 2.21.1, “Causes of Fire”

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