Air supply, service, spring and trailer brakes, and inspection — built from the Official Air Brake Handbook
Practice on the go and jump straight back to where you left off.
About the endorsement
In Ontario you need a Z endorsement on your licence to drive a vehicle with air brakes: most heavy trucks, many buses, and some RVs and farm vehicles. First-time applicants write a knowledge test at a DriveTest centre, then take a practical air brake test.
Since September 1, 2023, an online air brake learning module replaces the knowledge test at licence renewal, so the written test is now for people getting the endorsement for the first time. MTO doesn't publish the test's question count or pass mark.
ExamHub's free practice quiz has 200 original questions that follow the 12 chapters of the Official Air Brake Handbook (updated February 2026), from compressors and governors to brake adjustment checks.
What's covered
Categories follow the chapters of the Official Air Brake Handbook.
Try a few
Five sample questions from the question bank, with the answer and explanation.
Why: The handbook names the three foundation brake types as "S" cam, disc and wedge.
Why: The warning must activate before either tank pressure falls to 380 kPa (55 psi); most activate at 414 kPa (60 psi) or higher.
Why: It closes between 138 and 311 kPa (20 and 45 psi).
Why: The limit for a straight truck, tractor or bus is 21 kPa (3 psi).
Why: Stroke = 85 - 38 = 47 mm. The limit for a size 24 is 45 mm, so it exceeds it.
FAQ
No. Since September 1, 2023, an online air brake learning module replaces the knowledge test at renewal. The written test is for first-time Z applicants.
MTO doesn't publish either. ExamHub's 30-question test with an 80% target is a practice format, not the official one.
The Official Air Brake Handbook: braking systems, the air supply, service, spring and trailer brake subsystems, foundation brakes, driving demands, compliance, and inspection and adjustment checks.
The AZ/DZ quiz has an air brake section. This quiz is a deeper, stand-alone bank for people getting only the Z endorsement or wanting more air brake practice.
No. They're original practice questions written from the Official Air Brake Handbook.