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Question 1 of 65
Most pre-trip vehicle inspection failures are caused by which system?
Correct answer: A. Tires, wheels and rims
Why: AAMVA Section 2.1.2 lists tires, wheels, and rims as the most common cause of out-of-service violations during pre-trip inspections.
Question 2 of 65
When should you do an en-route inspection of your vehicle?
Correct answer: A. Within the first 50 miles, then every 150 miles or 3 hours, whichever comes first
Why: Federal regulations (49 CFR 392.9) require checking cargo and securing devices within the first 50 miles, then every 150 miles or 3 hours.
Question 3 of 65
What does the term "GVWR" stand for?
Correct answer: A. Gross Vehicle Weight Rating
Why: GVWR is the maximum loaded weight of a single vehicle as specified by the manufacturer.
Question 4 of 65
You should adjust your mirrors so that:
Correct answer: A. You can see along the sides of your vehicle and what is behind
Why: Mirrors must show the sides of the vehicle and what is behind. Section 2.4.4.
Question 5 of 65
When driving at night, you should:
Correct answer: A. Adjust your speed so you can stop within the range of your headlights
Why: Always be able to stop within the distance you can see ahead — about 250 feet on low beams.
Question 6 of 65
The most important hand signal you and your helper should agree on is:
Correct answer: A. Stop
Why: When backing with a helper, agree on a clear stop signal first — Section 2.7.2.
Question 7 of 65
When should you downshift before going down a long, steep hill?
Correct answer: A. Before starting down the hill
Why: Always downshift to a lower gear BEFORE starting down a grade. AAMVA Section 2.16.
Question 8 of 65
What should you do if your vehicle hydroplanes?
Correct answer: A. Release the accelerator and push in the clutch
Why: Take your foot off the accelerator and push in the clutch to slow down. Do not brake hard.
Question 9 of 65
Which of these statements about engine overheating is true?
Correct answer: D. Coolant should never be added while the engine is hot — wait until it cools
Why: Never remove a radiator cap on a hot engine — let it cool first to avoid burns.
Question 10 of 65
What is the most common cause of serious skids?
Correct answer: A. Driving too fast for road conditions
Why: Driving too fast for conditions accounts for the majority of serious commercial vehicle skids.
Question 11 of 65
Hydroplaning is more likely if tire pressure is:
Correct answer: A. Low
Why: Low tire pressure or worn tread increases hydroplaning risk.
Question 12 of 65
How do you correct a drive-wheel braking skid?
Correct answer: A. Stop braking and counter-steer
Why: Release the brakes to let wheels roll, then countersteer quickly.
Question 13 of 65
What is the minimum tread depth for front tires on a commercial vehicle?
Correct answer: A. 4/32 inch
Why: Federal rule: 4/32" minimum on steer tires, 2/32" on other tires.
Question 14 of 65
When approaching a railroad crossing in a placarded hazardous-materials vehicle, you must:
Correct answer: A. Stop between 15 and 50 feet from the nearest rail
Why: Placarded vehicles, buses, and tank vehicles must stop 15–50 feet from the nearest rail.
Question 15 of 65
What is the safest type of fire extinguisher for an electrical fire?
Correct answer: A. B:C or A:B:C extinguisher
Why: B:C and A:B:C dry chemical extinguishers are rated for electrical (C) fires.
Question 16 of 65
Distracted driving includes which of the following?
Correct answer: A. Texting, eating, adjusting radio, talking on a hand-held phone
Why: FMCSA defines distractions as anything that diverts attention — visual, manual, or cognitive.
Question 17 of 65
What is the minimum fine for a first conviction of using a hand-held mobile phone while driving a CMV?
Correct answer: A. $2,750
Why: 49 CFR 392.82 — civil penalty up to $2,750 per offense for the driver.
Question 18 of 65
You can lose your CDL for at least one year for the first offense of:
Correct answer: A. Driving under the influence of alcohol or drugs
Why: A first DUI conviction in any vehicle while holding a CDL leads to a minimum 1-year disqualification.
Question 19 of 65
What is the legal blood-alcohol concentration limit for CDL holders while operating a commercial vehicle?
Correct answer: A. 0.04
Why: CDL drivers operating a CMV are limited to 0.04 BAC — half the limit for non-commercial drivers in most states.
Question 20 of 65
How far ahead should you look while driving?
Correct answer: A. 12–15 seconds, about a quarter mile at highway speed
Why: Looking 12–15 seconds ahead lets you spot hazards early and avoid sudden moves.
Question 21 of 65
What is "off-tracking"?
Correct answer: A. Rear wheels follow a different path than the front wheels in a turn
Why: Off-tracking means rear wheels track inside the front wheels through a turn. The longer the vehicle, the worse the off-track.
Question 22 of 65
When making a right turn, you should:
Correct answer: A. Turn wide as you complete the turn, not as you start it
Why: Right turns: keep the rear of the vehicle close to the curb to prevent vehicles from squeezing between you and the curb.
Question 23 of 65
When you are merging onto a highway, you should:
Correct answer: A. Make sure you have a large enough gap before you merge
Why: Always wait for a gap; CMVs accelerate slowly and need extra space.
Question 24 of 65
Stopping distance equals:
Correct answer: A. Perception distance + reaction distance + braking distance
Why: Total stopping distance = perception + reaction + braking.
Question 25 of 65
At 55 mph on dry pavement, total stopping distance for a 40-ton truck is approximately:
Correct answer: A. About 300 feet (longer than a football field)
Why: Roughly 60 ft (perception) + 60 ft (reaction) + 170 ft (braking) ≈ 300 ft.
Question 26 of 65
Empty trucks:
Correct answer: A. May have longer stopping distances than loaded trucks
Why: Empty trucks have less traction; brakes designed for full loads can lock the wheels easily when empty.
Question 27 of 65
How many seconds of following distance do you need behind another vehicle if you weigh 80,000 lbs and are going 40 mph?
Correct answer: A. 8 seconds
Why: Use 1 second per 10 ft of vehicle length under 40 mph (8 sec for 80 ft truck), then add a second above 40 mph.
Question 28 of 65
What does ABS do?
Correct answer: A. Prevents wheels from locking up during hard braking
Why: ABS keeps wheels rolling so you keep steering control. It does not necessarily shorten stopping distance.
Question 29 of 65
When you double your speed, your braking distance:
Correct answer: A. Increases four times
Why: Braking distance grows with the square of speed: doubling speed quadruples braking distance.
Question 30 of 65
When checking the engine compartment, the engine should be:
Correct answer: A. Off and the parking brake set
Why: Engine off and parking brake set before you raise the hood.
Question 31 of 65
Which is NOT a sign of fatigue?
Correct answer: A. Increased reaction time and ability to focus
Why: Improved reaction time is the OPPOSITE of fatigue.
Question 32 of 65
You can avoid fatigue by:
Correct answer: A. Getting enough sleep before driving and taking rest breaks
Why: There is no substitute for sleep — short breaks and proper rest are the only real fixes.
Question 33 of 65
What is the most important reason for doing a pre-trip inspection?
Correct answer: A. Safety for you and other road users
Why: Safety. The legal requirement exists because unsafe vehicles cause crashes.
Question 34 of 65
What is "controlled braking"?
Correct answer: A. Apply brakes as hard as you can without locking the wheels
Why: Controlled braking means brake firmly without locking up. Used in emergencies on vehicles without ABS.
Question 35 of 65
What is "stab braking"?
Correct answer: A. Apply brakes fully, release when wheels lock, reapply when wheels start rolling
Why: Stab braking: full apply, release for wheel rotation, repeat. Used when ABS is not present and wheels lock.
Question 36 of 65
Which is true about texting while driving a CMV?
Correct answer: A. It is forbidden by federal regulation 49 CFR 392.80
Why: FMCSA bans CMV drivers from texting while driving — even at red lights.
Question 37 of 65
When you are being tailgated, you should:
Correct answer: A. Increase your following distance from the vehicle ahead and avoid sudden moves
Why: Open more space ahead so you do not have to brake suddenly.
Question 38 of 65
What is the minimum number of red reflective triangles required in a CMV?
Correct answer: A. Three
Why: You must carry at least 3 warning devices — typically reflective triangles.
Question 39 of 65
On a one-way street or divided highway, the warning triangles should be placed:
Correct answer: A. 10, 100, and 200 feet behind the vehicle toward approaching traffic
Why: On undivided two-way roads use 10/100/200 ft toward both directions. Stopped on the shoulder of a divided/one-way road, place them 10/100/200 ft toward approaching traffic.
Question 40 of 65
When entering a curve, you should:
Correct answer: A. Slow down before the curve and accelerate gently through it
Why: Brakes are most effective before the curve. Power lightly through.
Question 41 of 65
Black ice is most likely to form on:
Correct answer: A. Bridges, overpasses, and shaded areas
Why: Bridges freeze first because cold air circulates above and below.
Question 42 of 65
What is the proper way to test the service brakes on a tractor?
Correct answer: A. Roll forward at 5 mph and apply the brakes firmly
Why: Roll at about 5 mph and apply brakes firmly to check for proper stopping and pulling.
Question 43 of 65
Cargo securement: how many tie-downs are needed for an item 6 ft long that does not need extra securement?
Correct answer: A. Two
Why: For items longer than 5 ft and up to 10 ft, at least 2 tie-downs are required.
Question 44 of 65
What is the maximum amount of time on duty in any 8-day period for property-carrying CMV drivers?
Correct answer: A. 70 hours
Why: FMCSA: 70 hours in 8 days for carriers operating every day; 60 in 7 for carriers not every day.
Question 45 of 65
How long must drivers be off duty before resetting their 60/70-hour clock?
Correct answer: A. 34 consecutive hours
Why: A 34-hour off-duty period (the "34-hour restart") restarts the weekly clock.
Question 46 of 65
What is the maximum continuous driving time after 10 hours off duty?
Correct answer: A. 11 hours
Why: Drivers may drive up to 11 hours after 10 consecutive hours off duty.
Question 47 of 65
When are you required to take a 30-minute rest break?
Correct answer: A. After 8 cumulative hours of driving
Why: A 30-minute break is required after 8 hours of driving without at least a 30-minute interruption.
Question 48 of 65
When you are driving downhill, your brakes can fade because:
Correct answer: A. Heat reduces friction
Why: Excessive use overheats brakes; heat reduces friction (brake fade).
Question 49 of 65
What is the safe procedure for a long downgrade?
Correct answer: A. Use a lower gear, light steady brake applications, and watch the speedometer
Why: Lower gear before descending, snub-brake to control speed, never coast or ride brakes.
Question 50 of 65
Snub braking on a downgrade means:
Correct answer: A. Apply brakes firmly to slow 5 mph below safe speed, release, repeat
Why: Snub braking lets brakes cool between applications.
Question 51 of 65
Which lights must be used on a CMV from 30 minutes after sunset to 30 minutes before sunrise?
Correct answer: A. Headlights and clearance lights
Why: Federal rule requires headlights and identification/clearance lights during this period.
Question 52 of 65
Which of the following is a safe driving technique in fog?
Correct answer: A. Slow down, use low beams, watch for slow vehicles
Why: Low beams reduce glare reflected off fog. Slow down and increase following distance.
Question 53 of 65
How can you tell if your vehicle has hydraulic brake fade or failure?
Correct answer: A. Brake pedal sinks to the floor
Why: Hydraulic brake failure shows as a sinking pedal. (Air systems show pressure loss instead.)
Question 54 of 65
If your hydraulic brakes fail, you should:
Correct answer: A. Pump the brake pedal, downshift, and use the parking brake gradually
Why: Pumping may build temporary pressure; downshift, then progressively apply parking brake.
Question 55 of 65
What is the danger of driving with worn brake drums?
Correct answer: A. They can crack and lose braking ability
Why: Worn or cracked drums cannot dissipate heat and can fail.
Question 56 of 65
How can you reduce the chance of a crash with a hazard ahead?
Correct answer: A. Maintain a safe following distance and look 12–15 seconds ahead
Why: Early hazard recognition + space cushion = time to react.
Question 57 of 65
What is "rough acceleration"?
Correct answer: A. It can damage the drivetrain and cause loss of control
Why: Smooth, gradual acceleration prevents driveline damage and loss of control on slippery surfaces.
Question 58 of 65
You should test the parking brake by:
Correct answer: A. Engaging it and pulling against it gently in low gear
Why: Engage parking brake, gently apply throttle in low gear; truck should not move.
Question 59 of 65
What is the safest way to handle an oncoming vehicle that drifts into your lane?
Correct answer: A. Move right, slow down, sound horn, flash lights
Why: Move right, slow, signal — never move left into their original lane.
Question 60 of 65
What does the term "Jake brake" refer to?
Correct answer: A. Engine compression brake
Why: Jake (Jacobs) brake is an engine compression release — used to slow on grades.
Question 61 of 65
What is the proper procedure to recover from a tire blowout?
Correct answer: A. Hold the steering wheel firmly, stay off the brake, and gradually slow down
Why: Hold steering, ease off accelerator, do not brake — let it slow naturally before easing onto the shoulder.
Question 62 of 65
How can you tell if your tire blew out?
Correct answer: A. Loud "bang", vibration, and steering pull
Why: Symptoms include a bang, vibration, and pulling toward the failed tire.
Question 63 of 65
Which of the following materials is allowed to be loaded with class 1.1 explosives?
Correct answer: A. Nothing — they must be alone unless specifically allowed
Why: Segregation table forbids many combinations with 1.1/1.2 explosives.
Question 64 of 65
Reaction distance at 55 mph for an alert driver is approximately:
Correct answer: A. 60 feet
Why: About 60 ft for the average alert driver at 55 mph.
Question 65 of 65
Cargo should be inspected:
Correct answer: A. Before the trip and during the trip per federal regulation
Why: 49 CFR 392.9 requires the driver to inspect cargo and securement.