View instructions
The CDL general knowledge test is required to be taken by all CDL applicants. The Ohio CDL test consists of 50 questions. To pass, you must correctly answer at least 40 questions (80%). The general knowledge test covers the contents of the Ohio CDL Manual. All CDL applicants (Class A, B and C) must study the following sections: Driving Safely, Transporting Cargo Safely, Air Brakes (if you plan to operate vehicles equipped with air brakes), Vehicle Inspection Test, Basic Control Skills Test, Road Test. In addition, the Class A CDL test will include questions based on the Combination Vehicles section. Take this CDL practice test now to prepare for the actual OH general knowledge test! To get your CDL, you must pass both the knowledge and skills tests. CDL knowledge tests include: General Knowledge, Passenger Transport, Air Brakes, Combination Vehicles, Hazardous Materials, Tanker Vehicles, Doubles/Triples, School Bus, Firefighter. Depending on what class of license (A, B or C) and endorsements you need, you must take one or more knowledge tests. A special endorsement is also required to drive certain types of vehicles. The following endorsements may be used with a Class A, B or C CDL: HazMat (H), Tank Vehicles (N), Tank Vehicles Transporting Hazardous Materials (X) and Passenger Transport (P). The School Bus endorsement (S) is only available for Class A or B CDL, and the Doubles/Triples endorsement (T) is only available for Class A driver's licenses.
1. Checking the automatic transmission fluid level may require:
the vehicle to be parked downhill.
the engine to be running.
the 4-way emergency flashers to be activated.
2. If your brakes fail on a steep mountain downgrade, you should:
slow down until your vehicle comes to a complete stop.
decide what to do as soon as you know your brakes do not work.
stay on the road and keep looking for the next available escape ramp.
3. In coming down steep downgrades, you should:
select an appropriate speed.
go slowly enough so your brakes don't get too hot.
All of the above.
4. To back safely, you should NOT:
back as slowly as possible and use the lowest reverse gear.
look at your line of travel before you begin backing.
back to the right side whenever possible.
5. When you have to back, you should use a helper:
when you need to back on a curved path.
whenever possible.
only when you back up with a trailer.
6. Slippery surfaces usually:
make it more difficult to stop.
can cause lack of steering power.
make it easier to stop.
7. Fully loaded rigs:
are less likely to roll over than empty rigs.
are just as likely to roll over as empty rigs.
are much more likely to roll over than empty rigs.
8. Black ice is:
a thin layer of ice clear enough that you can see the road underneath it.
wet ice.
dirty snow.
9. If a tire fails while you are driving, you should:
stop on the roadway if possible.
stay off the brake until your vehicle has slowed down.
call your supervisor for instructions.
10. Bracing is used to:
increase the height of the vehicle’s center of gravity.
prevent movement of cargo.
make cargo easier to unload.
Page 1 of 5
Next page


Number of questions: 50
Correct answers to pass:40
Passing score:80%
Share This Online CDL Test
Rate this CDL Test
4.7 out of 5
based on 362 votes