West Virginia Combination Vehicles CDL Practice Test

This is a free 20-question practice test for the Combination Vehicles portion of the West Virginia Commercial Driver's License knowledge exam. Questions are pulled from a pool of 55 drawn from the AAMVA CDL Manual, which is the source document the West Virginia Division of Motor Vehicles uses to write its actual exam.

How it works: Click an answer. The correct choice highlights in green, and you'll see a short explanation. Aim for 85% or better before you sit for the real test in West Virginia.

Question 1 of 20

When backing a tractor-trailer in a straight line, you should:

Let the trailer drift wherever it goes
Make small steering corrections to keep the trailer in line
Apply heavy brake pressure
Use the trailer hand valve

Correct. When backing straight, watch the trailer in your mirrors and make small steering corrections to keep it tracking straight. Big corrections lead to jackknifing.

Question 2 of 20

When you are backing a trailer to the right, you should turn the steering wheel:

Left to start the trailer right
Right to start the trailer right
In the same direction every time
Never use the steering wheel; just push

Correct. When backing, the trailer goes opposite to the way you initially turn the steering wheel. To make the trailer go right (passenger side), start by turning the wheel left.

Question 3 of 20

When you check the fifth wheel during pre-trip, you look for:

Mounting to the frame is secure, no missing or damaged parts, no visible space between the upper and lower fifth-wheel plates, locking jaws around the kingpin shank, release arm in the locked position
Only the color
Only the bolts
Only the grease

Correct. Check mount, condition, gap, jaw engagement around kingpin shank (not the head), and release-arm lock position. Lubrication should be present but not excessive.

Question 4 of 20

To make a trailer go where you want when backing, the steering wheel should:

Be turned in the direction you want the trailer to go
Be turned opposite to the direction you want the trailer to go (then corrected)
Stay still
Be held lightly

Correct. Backing is opposite-direction steering: to swing the trailer right, turn the wheel left first, then correct as the trailer follows.

Question 5 of 20

When you supply air to the trailer for the first time after coupling, you should:

Wait until air pressure builds in the trailer reservoir, then test the trailer brakes by pulling out the trailer-supply knob
Drive away immediately
Disconnect the lines
Skip the test

Correct. Charge the trailer system. Then test the trailer brake function by tugging gently or pulling the trailer-supply knob to confirm trailer brakes apply.

Question 6 of 20

Most jackknifes happen because:

Drive wheels skid during braking on slippery surfaces
Brakes work too well
The road is dry
Cargo is too light

Correct. Loss of traction on the tractor drive axles during braking — typically on slick surfaces or with overly aggressive braking — causes a jackknife.

Question 7 of 20

When making a U-turn, a tractor-trailer needs:

Less space than a car
Substantially more space than a car — often more than a single intersection allows
The same space as a car
No turning space

Correct. Tractor-trailer turning radius is much larger than a car. A standard intersection rarely allows a U-turn — find a wider turning area.

Question 8 of 20

After connecting the trailer, before pulling away, you should always:

Visually inspect the fifth-wheel/kingpin connection from outside the cab
Just trust the gauge
Honk the horn
Set the trailer brake

Correct. Always visually confirm: no gap between fifth wheel and trailer plate, jaws closed around the kingpin shank, locking lever fully in place.

Question 9 of 20

The "rearward amplification" effect:

Is greatest in the lead trailer
Is greatest in the rear-most trailer of doubles or triples
Does not exist
Is the same in every trailer

Correct. Rearward amplification — the crack-the-whip effect — is most severe in the rear trailer of a multi-trailer combination.

Question 10 of 20

A high-mounted trailer kingpin is dangerous because:

It will not engage the fifth wheel and the trailer can drop
It is illegal
It improves coupling
It changes color

Correct. If the trailer is too high, the fifth wheel slides under without the kingpin engaging the locking jaws. The trailer is not coupled and can drop when you pull away.

Question 11 of 20

To recover from a trailer skid, you should:

Apply more brakes
Release the brakes to let the trailer wheels regain traction
Steer hard left
Honk

Correct. Release the brakes so the trailer wheels can rotate again and re-establish traction. Continued braking will worsen the skid.

Question 12 of 20

Off-tracking refers to:

Trailer brakes overheating
Trailer wheels following a tighter path than the tractor wheels in turns
The trailer pulling left
Tires losing tread

Correct. Off-tracking is the tendency for trailer wheels to follow a smaller-radius path than the tractor wheels through a turn, more pronounced with longer wheelbases.

Question 13 of 20

A "trailer skid" happens when:

Trailer wheels lose traction and the trailer slides outward
Tractor wheels lock
Brakes overheat
Cargo shifts

Correct. When trailer wheels lose traction (often from over-application of trailer brakes alone), the trailer can slide sideways — a trailer skid or trailer swing.

Question 14 of 20

When approaching a curve in a tractor-trailer, you should:

Brake during the curve
Slow down before entering the curve
Speed up
Maintain steady speed

Correct. Slow before entering the curve. Once in the curve, accelerate gently to maintain stability. Braking in a curve invites trailer skid or rollover.

Question 15 of 20

On a slippery surface, drive in:

Higher gears at higher RPM
A gear that minimizes torque to the drive wheels and brake earlier and gentler
The lowest gear
Whatever is fastest

Correct. Reduce engine power to drive wheels (higher gear, gentler accelerator) and brake earlier and gentler to avoid wheel spin or skid.

Question 16 of 20

Before uncoupling, you should:

Park on level ground, set the trailer parking brake, lower the landing gear, disconnect air and electrical lines, then release the fifth-wheel jaws
Just pull away
Disconnect electrical only
Drive forward fast

Correct. Proper sequence: park level, lower landing gear to support the trailer, disconnect lines, release jaws, then pull forward slowly. Skipping any step risks dropping the trailer.

Question 17 of 20

Length and weight increase what about a combination vehicle?

Stopping distance, off-tracking, blind spots, and time required for lane changes
Visibility
Speed
Acceleration

Correct. Longer, heavier rigs need more stopping distance, swing wider in turns, have larger blind spots, and require more time and space to change lanes.

Question 18 of 20

Cargo securement: the heaviest part of the load should be:

Loaded over the front axle area, with weight evenly distributed side to side
Loaded at the rear
Loaded on one side
Stacked on top

Correct. Loading heavy cargo to the front of the trailer over the drive axles helps with traction; loading to one side or top creates dangerous handling.

Question 19 of 20

Trailer rollover is more likely when:

Cargo is loaded low and centered
Cargo is loaded high or to one side, raising the center of gravity
Cargo is light
Trailer is empty

Correct. High cargo and uneven side-loading raise the center of gravity, increasing rollover risk on curves and ramps.

Question 20 of 20

A sliding fifth wheel that is unlocked or improperly secured can:

Slide unexpectedly during braking or acceleration, dangerously changing handling
Improve fuel economy
Save time
Have no effect

Correct. An unsecured sliding fifth wheel can shift during braking, changing the rig's handling unpredictably. Always verify the lock pin is engaged.

About the West Virginia Combination Vehicles exam

Most states administer 20 Combination Vehicles questions and require 80% to pass. The exam emphasizes the unique handling of articulated vehicles: how trailers track behind the tractor, how to prevent rollover, how to manage rearward amplification with multi-trailer combinations, and the correct sequence to couple and uncouple.

The West Virginia Division of Motor Vehicles follows the federal CDL standards established by FMCSA. To earn the Combination Vehicles credential, you must answer at least 80% of the questions correctly. Many candidates score lower the first time because the test pulls from a large pool — refreshing this page will give you a different mix of questions, drawn from the same authoritative source.

Want more practice? Try the full Combination Vehicles question bank or browse all West Virginia CDL practice tests.