Many trucks are equipped with air brakes. To drive one, your licence must carry a Z endorsement. The Z is earned through a separate knowledge test and practical sign-off based on the Official MTO Air Brake Handbook. It is not automatically part of the Class A or D test.
If a vehicle has air brakes and your licence has no Z, you may not legally drive it, regardless of your truck class.
🧠 Memory hook: "Class tells you the size; Z tells you the brakes." You can hold Class A or D without Z, but then only on hydraulic-brake vehicles.