iowa
CDL Practice Test

Below are practice questions for the Iowa CDL test. The site is free and you are able to take the practice test as many times as you need to as you prepare to obtain your Iowa CDL. The questions and answers covered in these Iowa practice CDL tests are taken from the Iowa DOT CDL manual. You will be presented with 40 questions and you must answer 34 questions correctly to pass. There is a 50-minute time limit. You may not go back once you answer a question. Click the "Start Test
" button below to begin.

1 / 40

An air system that is fully charged will typically have ___ psi of pressure.

125

250

200

2 / 40

You should check the_____when loading small tanks equipped with bulkheads.

percentage of water

fuel to air ratio

expansion rate

distribution of the weight

3 / 40

To maintain alertness during the trip, drivers should:

get 8-9 hours of sleep

avoid medications that cause drowsiness

all of these answers are correct

schedule trips during the daytime hours

4 / 40

How should the pintle hook be when backing a dolly under the second trailer?

in a halfway open position

removed from the dolly

in the unlatched position

in the latched position

5 / 40

What does the amount of liquid allowed in the tank depend on?

All answers listed.

Whether and how much the liquid will expand during the trip.

The size of the tank.

The legally allowed weight limits.

6 / 40

When checking for_____you are looking for dripping fluids or puddles on the ground below the transmission or engine.

coolant level

air brake system

leaks

power steering fluid

7 / 40

If you are carrying Division 1.2 or 1.3 materials, how far away must you park from the traveled portion of the roadway?

At least twenty feet

At least five feet

At least half a mile

At least ten feet

8 / 40

At the end of each shift you should:

Inspect your bus.

Report any defects.

Report any damage.

All of these answers are correct.

9 / 40

What might happen if a trailer is too high when you try to couple?

all answers listed

it may not correctly couple

the queen pin may fall off

the trailer may tip to the side

10 / 40

You should check____when loading the small tanks of a cargo tank with bulkheads.

none of the answers listed

the weight distribution

the fuel to air ratio

the expansion rate

11 / 40

The act of operating a motor vehicle in a selfish, bold, or pushy manner, without regard for the rights or safety of others is known as.

defensive driving

distracted driving

road rage

aggressive driving

12 / 40

The object that doesn't get checked at the side of the trailer is the:

Electrical/air connections

The landing gear

The locking pins/tandem release arm

The frame

13 / 40

Do you need to stop before a railroad crossing if you are hauling 100 pounds of Division 4.3 Dangerous When Wet material?

Only in populated areas

Only if you have more than 1,001 pounds of it

Yes

14 / 40

The front trailer supports should be____before driving away.

raised 1/3 of the way with the crank handle secured in its bracket

3 turns down from the top and the crank handle secured in its bracket

raised 1/2 way with the crank handle secured in its bracket

raised fully and the crank handle secured in its bracket

15 / 40

Select the accurate statement in regards to rolling up the landing gear to complete the coupling process.

you should use a high gear to make the process faster

you should leave the landing gear at the half way mark to make the uncoupling process easier later

you should use a low gear until the tractor is supporting the trailer

you should grease the landing gear the increase the speed of the process

16 / 40

The two other places where the hazardous identification number must appear are:

On a temporary license plate holder and the steering wheel.

On the gas tank and a sticker in the glove compartment.

Any bulk packaging and the cargo tanks.

On the back of the truck and inside the glove compartment.

17 / 40

While driving on a clear night with low beam headlights, you should be able to stop within:

2 lengths of your vehicle.

The distance you will travel in the next 20 seconds.

The distance you can see ahead of you.

Half of a football field.

18 / 40

You should keep a minimum of ____between another vehicle and the double trailer with 100 ft truck driving at 30 mph.

13 seconds

10 seconds

8 seconds

15 seconds

19 / 40

Surge affects the handling of a tanker by:

Moving the truck in the direction the liquid flows in.

None of the answers listed.

Increasing the wind drag.

Allowing you to take tighter turns.

20 / 40

Select the false statement about suspension:

Check to make sure torsion bars and/or arms are lubricated.

Check for shifted, missing, or cracked leaf springs.

Check for broken or cracked spring hangers.

Check for distorted or broken coil springs.

21 / 40

At what pressure is the safety valve in the air compressor tank set to open?

225 psi

125 psi

150 psi

100 psi

22 / 40

When there is a hazardous materials emergency. You should:

Prevent smoking and keep open flames away.

All of these answers are correct.

Keep people away and warn them of the danger.

Contact emergency authorities.

23 / 40

After coupling with a trailer, what position should the front trailer supports be in before driving away?

in the fully raised position with the crank handle secured to its bracket

raised to the top and then taken 3 cranks down and the crank handle stored in its bracket

raised half way with the crank handle stored in the cab

none of the answers listed

24 / 40

Is it mandatory that all vehicles with air brakes have low air pressure warning signals?

for large vehicles only

for small vehicles only

yes

25 / 40

The main reason you should pull the dolly out from under a trailer before disconnecting it from the trailer in front is:

to provide additional lateral stabilization to the front trailer

so the rear-trailer's air brake system will stay charged and keep the trailer wheels locked to prevent rolling

it is possible that the dolly tow bar could fly up making it difficult to re-couple

removing the dolly before uncoupling is not the correct procedure

26 / 40

Where are shut-off valves located?

at the front and back of the trailer

at the back of the trailer

either at the front or the back of the trailer

at the front of the trailer

27 / 40

Which of the following types of cargo can never be carrier on a bus with riders?

Emergency hospital supplies.

Emergency drug shipments.

Emergency tear gas.

Small arms ammunition (orm-d).

28 / 40

When you have a major leak in the service line and you apply pressure to the brakes, the service air pressure will escape and:

the tractor spring brakes will kick on

the trailer emergency brakes will kick on

the hand valve will stop functioning

the trailer tank pressure will be gone

29 / 40

You should_____when an emergency requires you to quickly stop your tanker.

turn off the abs and brace for impact

use the emergency brakes only

use stab or controlled braking

keep a firm pressure on the brake pedal

30 / 40

What action should you take before driving while drowsy?

drink a cup of coffee

pull off the road and get some sleep

drink energy drinks

open your vehicle windows for some fresh air

31 / 40

Which of the following statements about downshifting is NOT true?

downshift when you get to the bottom of a hill

downshift before climbing a hill

downshift before entering a curve

downshift before starting down a hill

32 / 40

At 55 miles-per-hour it takes about 6 seconds to stop a fully loaded truck and the braking distance is:

about two truck lengths

about two car lengths

about the length of a football field or 100 yards

about 1/4 mile

33 / 40

The golden rule for school buses when approaching and crossing railroad tracks is:

Stop, look, and turn on the radio lights overhead.

None of these answers are correct.

Stop, look, and listen.

Stop, go, and stop.

34 / 40

When driving tank vehicles you should:

Maintain the posted speed limit as you enter the curve.

Decrease your speed before entering a curve and then accelerate through it.

None of the answers listed.

Come to a stop before entering a curve and then accelerate through it.

35 / 40

Select the true statement in regards to an application pressure gauge:

it is connected to the generator

when accelerating it releases air

it prevents the brakes from failing

it shows how much air pressure you are applying to the brakes

36 / 40

In the event of an accident you should remember to do the following EXCEPT:

notify authorities

protect the area

stop any bleeding and keep the victims warm

move the victims out of the way immediately

37 / 40

You should follow the posted speed limits for curves and be aware of:

The posted speed limit may be too high for safety.

A rollover may occur even when driving at the posted speed limit.

All answers listed.

The higher center of gravity on a tank truck.

38 / 40

When inspecting your bus, you must make sure that:

Every handhold and railing is secure.

All of these answers are correct.

Emergency exit handles are secure.

Rider signaling devices are working.

39 / 40

What are spring brakes?

they are big springs with air pressure in them if the air pressure decreases, the brakes are applied

none of the answers listed

they are large springs that are held closed by air pressure if the air pressure is increased the brakes are applied

they are powerful springs that are restrained by air pressure when the air pressure is removed, the brakes are applied

40 / 40

Select the true statement in regards to quick steering movements and double trailers:

it is easier to tip doubles and triples from quick steering movements than other vehicles

it is easier to countersteer doubles/triples than other vehicles

nothing will occur

you should apply a firm pressure to the brake pedal at the same moment you do quick steering movements

Your score is

The average score is 0%

5/5 - (1 vote)

CDL Category Practice Tests

CDL Practice Test

How To Get An iowa Commercial Drivers License

Individuals may apply for their CDL starting at age 18. To be eligible for interstate driving as well as HazMat and Doubles/Triples applicants must be 21 years of age or older. All individuals applying for an Iown CDL must present a Medical Examiner’s Certificate according to the United States Federal Regulations.

If any one of the descriptions below is true about an applicant, they will be disqualified from receiving their CDL.

Driver posses more than one driver’s license.
Driver was convicted of driving under the influence in the past 24 months.
Driver has a suspended, denied, canceled, or revoked driver’s license.

Endorsements
H – Hazardous Materials
N – Tank Vehicle
T – Doubles/Triples
X – Hazmat and Tank Comb
P – Passenger Vehicle
S – School Bus

Drivers must take a knowledge test as well as a practical skills test to showcase their knowledge of commercial driving laws and their ability to operate a commercial vehicle.

Hit the Open Road

iowa CDL License Test Tips

Applicants must complete a general knowledge test to display their understanding of commercial driving laws. The general knowledge exam is comprised of 50 questions. Those seeking a Class A CDL will need to complete an additional 20 question test on combination vehicles. Applicants seeking additional endorsements will need to take an additional test on the endorsement topic. The Passenger, Tank, and Doubles/Triples Endorsements are 20 question tests. Removing the Air Brake Restriction, the Iowa Operator and School Bus Endorsements are 25 questions. The Hazmat Endorsement is a 30 question test. All applicants must pass the respective assessments with a score of 80 percent or better to receive their Iowa CDL permit.

A skills assessment is required of all applicants. This assessment is comprised of three parts, which are the pre-trip inspection, basic controls skills, and on-road driving. Individuals applying for their P and S endorsements will be required to take the skills test in the respective vehicle for their endorsement.

Additional Information

Information on the Iowa Department of Transportation

The Iowa Department of Transportation administers CDL requirements and testing in Iowa. To get more information contact them via:

Website: https://iowadot.gov/DriversVehicles#CommercialDrivers

Phone: 515.239.1101

Additional Iowa CDL Helpful Links

Please use the links below to access more valuable Iowa CDL testing resources and to learn more about practice driving tests for the state of Iowa.

iowa CDL Practice Test

CDL Category Practice Tests

CDL Practice Test

How To Get An iowa Commercial Drivers License

Hit the Open Road

iowa CDL License Test Tips

Additional Information

Information on the Iowa Department of Transportation

Additional Iowa CDL Helpful Links

iowa
CDL Practice Test