Ontario Commercial Drivers License Class D Practice Test 3

Commercial Driver HQ is a website focused on helping new commercial drivers in all provinces and territories in Canada.

Our FREE practice tests are designed to help you succeed when it comes time to write the real test.

Each license type has 5 tests to help you study and become familiar with the rules and regulations of commercial driving. The tests are not identical to the license test you will need to pass, but the questions are similar to what you will find on the real deal.

Compatible on desktop, mobile, and tablet, you can take these tests anywhere you have internet access.

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Created by Commercial Driver HQ

Ontario Class D Practice Test 3

A 20 question practice test to help prepare you for the Class DZ knowledge test in Ontario

1 / 20

If brake chambers on opposite side of an axle are different sizes, this may cause?

2 / 20

Drivers need to perform a vehicle inspection every ________.

3 / 20

As an operator you are required to have vehicles and trailers inspected how often?

4 / 20

How many previous days must a drivers log keep track of?

5 / 20

What information does a CVOR record contain?

6 / 20

What does this rectangle sign mean?

7 / 20

What does this sign mean?

8 / 20

If you feel sleepy while driving you should?

9 / 20

What should you do when the air brakes low pressure warning comes on?

10 / 20

When inspecting your brakes, you must?

11 / 20

Read tire tread depth must be more than ______.

12 / 20

What does this orange sign mean?

13 / 20

The supply tank should discharge more moisture than any other tank?

14 / 20

What does a governor do in an air brake system?

15 / 20

Cut in pressure level must never fall below __________.

16 / 20

What does this yellow sign mean?

17 / 20

What does this sign mean?

18 / 20

After an inspection you find major defects in some parts, what do you do?

19 / 20

What does a driver need to transport dangerous goods?

20 / 20

Which of these vehicle driver’s are exempt from the Hours of Service Regulations?

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The average score is 89%


Want to know more? Learn all about getting your DZ drivers license in Ontario

We do our best to keep the questions current and accurate. The testing centres may change the questions on the knowledge tests at any time. Always be prepared for surprises.

Many of the answers to the questions can be found in the driver hand books or learning materials your province provides.

DISCLAIMER: CDHQ is not affiliated with DriveTest or the MTO. These practice tests should not be considered official tests and you are not granted a license for completing them. Our tests are simply a practice tool to help prepare yourself for the real test.