Try 20 CDL Practice Questions Free

Question 1

What is the correct way to correct a trailer's path if it starts to drift off course while backing?

Accepted Answer

Make an immediate, small steering correction or pull up to realign.

Answer

Apply the trailer hand valve immediately.

Answer

Wait until it drifts significantly before making a large steering correction.

Answer

Accelerate to straighten it quickly.

Question 2

When turning on the ignition of a vehicle equipped with an Anti-lock Braking System (ABS), what should the yellow ABS indicator light on the dashboard do?

Accepted Answer

Turn on momentarily and then go out.

Answer

Flash rapidly until the vehicle reaches 5 mph.

Answer

Remain off completely unless there is a fault.

Answer

Stay on continuously while the engine is running.

Question 3

You are driving past an accident scene on the highway. What secondary hazard should you prepare for?

Accepted Answer

Other drivers 'rubbernecking' and slamming on their brakes or wandering out of their lane.

Answer

Law enforcement impounding your vehicle for being too close.

Answer

Emergency vehicles deliberately ramming your truck to clear the road.

Answer

The accident catching fire and instantly exploding.

Question 4

When you are passing a vehicle on the highway, what should you assume about the other driver to maintain maximum safety?

Accepted Answer

They might suddenly drift into your lane because they do not see you.

Answer

They will move onto the shoulder to give you room.

Answer

They will maintain a perfect center lane position.

Answer

They will speed up to prevent you from passing.

Question 5

If you are driving in a snowstorm, why is it important to clear snow and ice from the roof of your truck or trailer?

Accepted Answer

It prevents sheets of ice from flying off and striking other vehicles.

Answer

It prevents the roof from caving in under the weight.

Answer

It keeps the cargo inside warmer.

Answer

It reduces the weight of the vehicle, saving fuel.

Question 6

Which of the following is true regarding mirrors?

Accepted Answer

There are blind spots that your mirrors cannot show.

Answer

You only need to check your mirrors when you intend to change lanes.

Answer

You should rely solely on your mirrors when changing lanes.

Answer

Mirrors can completely eliminate blind spots if adjusted correctly.

Question 7

In an emergency, why might steering to avoid an obstacle be better than braking?

Accepted Answer

You can usually steer to avoid an obstacle more quickly than you can stop the vehicle.

Answer

Steering causes less wear on the tires.

Answer

Braking is illegal in emergency maneuvers.

Answer

Steering prevents the load from shifting.

Question 8

If you begin to feel sleepy while driving at night, what is the safest course of action?

Accepted Answer

Pull off the road at a safe place and get some sleep

Answer

Turn up the radio and roll down the window

Answer

Slap your face and chew gum

Answer

Drink heavily caffeinated beverages and continue driving

Question 9

Because retarders apply braking power only to the drive wheels, what can happen if they are used on wet or icy roads?

Accepted Answer

The drive wheels can lock up and cause a skid

Answer

The vehicle will stop much faster than on dry roads

Answer

The transmission will automatically shift to neutral

Answer

The front wheels will lose steering control immediately

Question 10

When driving through a work zone, where should you focus your visual search?

Accepted Answer

Scanning for workers, changing traffic patterns, and sudden brake lights ahead.

Answer

On the pavement directly in front of your bumper.

Answer

On the heavy construction equipment.

Answer

On the vehicle immediately ahead of you only.

Question 11

If your vehicle has automatic air tank drains, what must you remember?

Accepted Answer

They may be equipped with electric heating devices to prevent freezing in cold weather.

Answer

They never need to be inspected or maintained.

Answer

They require a special key to operate.

Answer

They only drain water, so oil must still be drained manually.

Question 12

How can you check if the antilock braking system (ABS) is working during the pre-trip inspection?

Accepted Answer

The ABS warning light on the dash should turn on and then off when you start the vehicle.

Answer

The wheels should lock up when you hit the brakes.

Answer

The ABS light should remain constantly illuminated while driving.

Answer

You must use a diagnostic scanner on the engine computer.

Question 13

What is a common sign that the glad hand seals are damaged or missing?

Accepted Answer

You will hear a loud hissing sound when air is supplied to the trailer.

Answer

The steering will feel very heavy.

Answer

The tractor parking brakes will not release.

Answer

The trailer lights will not turn on.

Question 14

How often should you drain the air tanks in a dual air brake system if they are equipped with manual drain valves?

Accepted Answer

At the end of each driving day.

Answer

Every 1,000 miles.

Answer

Only when the low air pressure warning comes on.

Answer

Once a week.

Question 15

What connects to the blue glad hand on the trailer?

Accepted Answer

The blue air line from the tractor

Answer

The hydraulic hose

Answer

The electrical pigtail

Answer

The red air line

Question 16

To avoid rolling over during a high-speed emergency avoidance maneuver, what is the best rule for steering?

Accepted Answer

Only steer enough to clear the hazard, then smoothly steer back

Answer

Steer fully to the lock position to clear it fast

Answer

Use only the palm of one hand to rotate the wheel quickly

Answer

Steer sharply back and forth to keep the tires warm

Question 17

What is the proper angle of the fifth wheel before coupling a tractor to a semi-trailer?

Accepted Answer

Tilted down towards the rear of the tractor

Answer

Perfectly flat and horizontal

Answer

Tilted up towards the rear of the tractor

Answer

Tilted towards the left or right side of the frame

Question 18

What is the driver's responsibility regarding placards before moving a loaded vehicle?

Accepted Answer

To ensure the correct placards are securely affixed and visible on all four sides.

Answer

To design and print the placards.

Answer

To place the placards inside the cab window.

Answer

To write the UN number on the placards using a pen.

Question 19

To safely control a tanker from a dead stop, you should:

Accepted Answer

Accelerate slowly and smoothly to prevent a severe backward surge.

Answer

Turn the steering wheel back and forth.

Answer

Accelerate quickly to bypass the surge.

Answer

Skip gears to reach cruising speed faster.

Question 20

A post-trip inspection of a passenger bus must be conducted:

Accepted Answer

At the end of each shift or trip.

Answer

Only after night driving.

Answer

At the end of every week.

Answer

Only if a defect is noticed.