What it takes to get an AZ licence in Ontario
An AZ licence is a full Class A licence with a Z (air brake) endorsement. It lets you drive any tractor-trailer combination, a vehicle pulling double trailers, and the trucks covered by Classes D and G. To get there you must be at least 18, hold a valid Ontario licence other than G1, G2, M, M1 or M2, pass a vision test, submit a medical report and pass a knowledge test about operating large trucks and tractor-trailers. You then complete mandatory entry-level training (MELT) and pass a road test in a full Class A vehicle. From January 1, 2027, you must also have held a Class G or higher licence for at least 6 months before the Class A road test.
| Step | What to expect |
|---|---|
| Class A knowledge test | Multiple choice, based on the Official MTO Truck Handbook. Bring identification, a completed medical report form and the test fee |
| Air brake (Z) knowledge test | A separate written test at a DriveTest centre, based on the Official Air Brake Handbook, followed by a practical air brake test |
| Pass mark | DriveTest says knowledge tests need a total score of at least 80% |
| Time limit | None. DriveTest says knowledge tests are not timed and typically take 20 to 30 minutes |
| Languages | DriveTest offers computerized commercial knowledge tests in 20 languages |
| Mandatory entry-level training | At least 103.5 hours with an approved provider, completed before the Class A road test |
DriveTest says knowledge tests have two or three sections and that results are valid for one year, so if you try again within that year you only redo the sections you did not pass. The official pages we checked do not give an exact question count for the Class A or air brake knowledge tests. Our simulation uses 40 questions, 10 from each of our four areas. Check DriveTest before your visit in case anything has changed.
What our questions cover
Every question is written from the official handbooks and the Ontario regulations they point to. The bank has four areas:
- Licensing and commercial rules (39 questions). Class A, AR and D, MELT, the manual transmission restriction, medical reports, CVOR, zero tolerance for alcohol and drugs, speed limiters, following distance, impoundment and roadside inspections.
- Hours of service and inspections (46 questions). Daily driving, on-duty and off-duty limits, the 7-day and 14-day cycles, daily logs and the 160 km exemption, daily inspections under Schedule 1, major and minor defects, tires and the annual inspection decal.
- Air brakes (Z) (73 questions). The compressor, governor and tanks, pressures, warning devices, service and spring brakes, trailer brakes and gladhands, stopping distance, pushrod stroke and adjustment limits, and the full pre-trip air brake check.
- Loads, coupling and handling (42 questions). Cargo securement checks, size and weight limits, coupling and uncoupling, off-tracking, skids and jackknifing, long grades, breakdowns, fires and railway crossings.
Numbers that come up again and again
- Hours of service. At least 10 hours off duty a day, no more than 13 hours driving, no driving after 14 hours on duty, and no driving once 16 hours have passed since your last 8 consecutive hours off.
- Air pressures. Cut-in never below 552 kPa (80 psi), cut-out never above 1000 kPa (145 psi), low air warning by 380 kPa (55 psi), and spring brakes starting to apply around 414 kPa (60 psi).
- Air brake checks. Build-up from 85 to 100 psi within two minutes at 600 to 900 rpm, and an air loss limit of 3, 4 or 6 psi per minute depending on how many trailers you pull.
- Stopping distance. Double the weight and you double it. Double the speed and it goes up four times. Double both and it goes up eight times.
- Loads and size. Re-check cargo within 80 km, then after a change of duty status, 3 hours or 240 km. Width 2.6 m, height 4.15 m, and a 23 m combination length for most rigs.
How our air brake and inspection questions work
The handbooks use diagrams of gauges, brake chambers and couplers. Our site does not use images, so every question describes the part, the gauge reading or the situation in words. Defect questions follow the major and minor defect lists in Schedule 1 of the daily inspection regulation, which is the schedule you carry for a truck or tractor-trailer.
How to prepare
Read the Official MTO Truck Handbook and the Official Air Brake Handbook first. Then practise one area at a time until you score well above 80%, and finish with full 40-question simulations. Read every explanation, including the ones you got right, because many questions test an exact number, a pressure or the order of a procedure. MELT and the practical air brake test will build on the same knowledge.
Aptitude Tests Canada is an independent practice platform. We are not affiliated with or endorsed by the Ministry of Transportation, DriveTest or the Government of Ontario. Our questions are original practice questions written from the public handbooks and regulations, not real test questions.
Three worked examples
One question from different sections of the full pack, with the answer and explanation.
A Class A licence lets you drive a motor vehicle towing vehicles whose total gross weight is over how much?
- 4,500 kg
- 4,600 kg
- 6,000 kg
- 11,000 kg
Ontario's hours-of-service rules apply to commercial motor vehicles with a gross or registered gross weight over how much?
- 4,500 kg
- 4,600 kg
- 6,000 kg
- 11,000 kg
You want to drive a medium-duty truck with air-over-hydraulic brakes in Ontario. What do you need on your licence?
- Nothing beyond your Class G
- A restricted Class A (AR)
- A dangerous goods certificate
- A Z (air brake) endorsement