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Missouri CDL General Knowledge Practice Questions - Missouri Commercial Driver License General Knowledge Test Exam
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Question
1
of 25
QUESTION 1 / 25
What is the purpose of the first walk-around during a commercial vehicle inspection?
Choose one answer below.
A
To get an overall view of the vehicle condition and look for obvious damage or leaks
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B
To replace the required brake test
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C
To verify the cargo paperwork before looking at the vehicle
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D
To warm the engine before checking fluids
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QUESTION 2 / 25
During the engine-compartment check, which group of items should be inspected?
Choose one answer below.
A
Paint color, radio antenna, and registration card
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B
Oil, coolant, power steering fluid, belts, hoses, and leaks
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C
Only the windshield washer fluid
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D
Only the parts that can be checked without opening the hood
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QUESTION 3 / 25
What minimum tread depth is required on front steering-axle tires of a commercial motor vehicle?
Choose one answer below.
A
2/32 inch
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B
3/32 inch
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C
4/32 inch
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D
6/32 inch
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QUESTION 4 / 25
What minimum tread depth is required on most tires other than front steering-axle tires?
Choose one answer below.
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
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QUESTION 5 / 25
Which emergency equipment should be in a commercial motor vehicle?
Choose one answer below.
A
A fire extinguisher, spare electrical fuses if needed, and warning devices such as three reflective triangles
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B
A shovel, tow chain, and road atlas
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C
A first-aid kit only
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D
A CB radio and spare antenna
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QUESTION 6 / 25
Why should brake hoses and air lines be checked during inspection?
Choose one answer below.
A
To make sure they are painted the same color
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B
To find cuts, cracks, abrasions, leaks, or contact with moving or hot parts
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C
To measure vehicle length
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D
To verify the driver has an air brake endorsement
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QUESTION 7 / 25
Which lights must be checked during a pre-trip inspection?
Choose one answer below.
A
Headlights only
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B
Turn signals only
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C
Headlights, brake lights, turn signals, four-way flashers, clearance lights, and reflectors
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D
Only lights used at night
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QUESTION 8 / 25
A driver finds a cracked brake drum during pre-trip inspection. What should the driver do?
Choose one answer below.
A
Drive slowly to the first delivery
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B
Do not operate the vehicle until the defect is repaired
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C
Apply the parking brake while driving to compensate
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D
Record it after the trip only
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QUESTION 9 / 25
What should you do if a tire has a sidewall bulge?
Choose one answer below.
A
Reduce air pressure and continue
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B
Replace or repair the tire before operating the vehicle
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C
Move it to the steering axle
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D
Ignore it if tread depth is legal
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QUESTION 10 / 25
When starting a CMV from a stopped position, what should you do before moving?
Choose one answer below.
A
Rev the engine to maximum rpm
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B
Release the clutch quickly to test traction
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C
Check traffic, mirrors, and blind areas, then move smoothly
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D
Turn on four-way flashers for all starts
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QUESTION 11 / 25
What is the safest general rule for backing a commercial vehicle?
Choose one answer below.
A
Back as fast as possible to spend less time blocking traffic
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B
Avoid backing when possible and use a helper when available
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C
Use only the left mirror
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D
Sound the horn continuously and do not stop
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QUESTION 12 / 25
Why do large vehicles often need to swing wide before a right turn?
Choose one answer below.
A
The rear wheels follow a shorter path than the front wheels
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B
The steering wheel turns more slowly on trucks
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C
It keeps the vehicle from exceeding speed limits
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D
It is required only when empty
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QUESTION 13 / 25
When backing with a helper, what should you do if you lose sight of the helper?
Choose one answer below.
A
Keep backing slowly
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B
Stop immediately until the helper is visible again
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C
Turn toward the helper's last position
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D
Use the horn and continue
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QUESTION 14 / 25
Why should you check overhead clearance before driving under a bridge or canopy?
Choose one answer below.
A
Vehicle height can exceed posted or actual clearance
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B
All bridges have the same clearance
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C
Clearance only matters for empty trailers
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D
Mirrors automatically show roof clearance
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QUESTION 15 / 25
Why should a loaded truck slow well below advisory speeds before a curve?
Choose one answer below.
A
Advisory speeds are usually intended for smaller vehicles and trucks have higher centers of gravity
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B
Loaded trucks can safely take curves faster than cars
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C
Braking hard inside the curve prevents rollover
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D
The trailer brakes steer the trailer through the curve
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QUESTION 16 / 25
When parking on a downgrade, what should a driver generally do after setting the parking brake?
Choose one answer below.
A
Leave the transmission in neutral and walk away
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B
Turn wheels as appropriate, use chocks when required, and make sure the vehicle is secure
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C
Release all brakes to avoid brake wear
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D
Leave the engine at high idle
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QUESTION 17 / 25
Why must a CMV driver wear a seat belt?
Choose one answer below.
A
It is required and helps keep the driver in control during a crash or sudden maneuver
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B
It is optional at low speeds
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C
It is required only when hauling passengers
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D
It substitutes for mirror checks
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QUESTION 18 / 25
What steering method is recommended for most CMV driving?
Choose one answer below.
A
One-hand steering at all times
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B
Holding the wheel securely with both hands when practical
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C
Letting the wheel slide freely after every turn
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D
Steering only with the palms
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QUESTION 19 / 25
When should you shift gears on a downgrade?
Choose one answer below.
A
After the vehicle is already speeding up
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B
Before starting down the grade
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C
Only after applying the parking brake
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D
At the bottom of the hill
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QUESTION 20 / 25
What is the safest speed for a commercial vehicle?
Choose one answer below.
A
Always the posted limit
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B
A speed that lets you stop within the distance you can see and control the vehicle for conditions
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C
The same speed as passenger cars in all weather
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D
The highest speed that maintains traffic flow
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QUESTION 21 / 25
In good conditions at highway speed, why do CMV drivers need a long following distance?
Choose one answer below.
A
Large vehicles usually need more time and distance to stop
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B
Trucks stop shorter than cars because they have more brakes
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C
Following closely improves visibility
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D
Air brakes work instantly with no delay
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QUESTION 22 / 25
What should you do when another driver tailgates your CMV?
Choose one answer below.
A
Increase your following distance from traffic ahead and avoid sudden braking
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B
Brake hard to warn the driver
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C
Speed up until the tailgater disappears
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D
Drive on the shoulder
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QUESTION 23 / 25
What is "overdriving your headlights"?
Choose one answer below.
A
Driving so fast at night that stopping distance is longer than the area lit by your headlights
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B
Using low beams in fog
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C
Checking headlights during pre-trip
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D
Using headlights during the day
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QUESTION 24 / 25
Which factors increase total stopping distance?
Choose one answer below.
A
Perception distance, reaction distance, brake lag, braking distance, speed, weight, and road conditions
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B
Only the number of axles
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C
Only the color of the trailer
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D
Only whether the vehicle is empty
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QUESTION 25 / 25
What is the correct way to use brakes on a long downgrade?
Choose one answer below.
A
Use a low gear and apply brakes only enough to control speed without overheating them
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B
Ride the brakes continuously at full pressure
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C
Shift to neutral and coast
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D
Use only the trailer hand valve
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