310T Red Seal — Truck & Transport Mechanic

About the 310T Red Seal Exam — Truck & Transport Mechanic

The 310T Truck and Transport Mechanic Red Seal exam is Canada's nationally recognized certification for diagnosing, repairing, and maintaining heavy-duty trucks, trailers, and transport equipment. Passing the 310T exam earns you the Red Seal endorsement on your certificate; the trade is designated Red Seal in all ten provinces and three territories, and Red Seal says the endorsement facilitates labour mobility.

The exam consists of 135 multiple-choice questions based on the 2022 Red Seal Occupational Standard (RSOS), and the pass mark is 70%. You have 4 hours to complete the exam.

Official 310T Exam Breakdown (red-seal.ca)

Red Seal publishes how the 135 questions on the real 310T exam are distributed across its Major Work Activities:

• A — Common Occupational Skills — 8 questions (6%)
• B — Services, diagnoses and repairs engines and supporting systems — 21 questions (16%)
• C — Services, diagnoses and repairs air systems and brake systems — 17 questions (13%)
• D — Services, diagnoses and repairs electrical and electronic systems — 22 questions (16%)
• E — Services, diagnoses and repairs drive trains — 17 questions (13%)
• F — Services, diagnoses and repairs steering, chassis/frames, suspensions, tires, wheels and hubs — 18 questions (13%)
• G — Services, diagnoses and repairs cabs — 5 questions (4%)
• H — Services, diagnoses and repairs trailers — 8 questions (6%)
• I — Services, diagnoses and repairs climate control systems — 7 questions (5%)
• J — Services, diagnoses and repairs hydraulic systems — 8 questions (6%)
• K — Services, diagnoses and repairs hybrid and electric vehicles (EV) — 4 questions (3%)

Every question is four-option multiple choice with one correct answer, the writing time is four hours and the pass mark is 70%. Sources: 310T exam information, red-seal.ca (question format) and the Red Seal Exam Preparation Guide (writing time and pass mark). Exams are periodically rewritten to updated occupational standards, so check that page before you book.

What this question bank covers

These are the topic areas in this practice bank and what each one covers. The real 310T exam has 135 questions and a four-hour writing time. How those questions are distributed across the official blocks is published by Red Seal — see the 310T exam information page.

• Air Brake Systems — The largest topic in this practice bank (35 of 161 questions). Covers CVSA Level 1 inspections, S-cam and disc brake adjustment, dual-circuit air systems, ABS/ATC, glad hands, and brake fade. On the official exam, air systems and brake systems is Block C with 17 of the 135 questions (13%) — highly practical, but smaller than electrical (22) and engines (21).
• Diesel Engine Systems — Fuel injection (common-rail, HEUI), EGR, DPF/DEF aftertreatment, turbocharger operation, cooling systems, and engine diagnostics. Expect J1939 fault codes.
• Electrical & Electronic Systems — CAN bus (J1939/J1587), multiplexing, chassis wiring, ABS module diagnostics, telematics, and 12V/24V systems. Practise reading wiring diagrams.
• Drivetrain & Wheels — Manual and automatic transmissions (Allison, Eaton Fuller), rear axle differentials, driveshaft angles, tire sizing/inflation (TPMS), and wheel-end bearings.
• Regulations & Inspections — National Safety Code (NSC) standards, Commercial Vehicle Safety Alliance (CVSA) inspection levels, federal Hours of Service, dangerous goods placarding (TDG), pre-trip/post-trip inspection requirements.

Exam Strategy for 310T

Air brakes matter, but they are not the biggest block. Air systems and brake systems are Block C with 17 of the 135 questions (13%) on the official breakdown; electrical and electronic systems (22) and engines and supporting systems (21) are larger. Understand the dual-circuit system, CVSA out-of-service criteria, and brake timing standards cold.

Know your fault codes. Learn J1939 fault code structure (SPN/FMI): know what the parameters mean, not just the code numbers. Practise working from a described symptom to its cause using live data.

Know the inspection rules. The 2022 Red Seal Occupational Standard has truck and transport mechanics read and interpret the government regulations that specify vehicle inspection procedures and roadworthiness requirements. For this bank's Regulations & Inspections topic, memorize the NSC inspection intervals and CVSA inspection levels.

How to Use This Practice Tool

This practice tool includes 161 questions across the five topic areas of this bank at three difficulty levels — Easy, Medium, and Hard. Use Topic Filter to drill your weakest areas. Use Mock Exam Mode (25, 50 or 100 questions, 90 seconds each) to practise under timed conditions. Check Wrong Bank (📕 tab) to review every question you missed. After each session, review the full explanation — not just whether you got it right.

Related reading: How to Pass the 310T Red Seal Exam | 310T Salary Guide | Truck & Transport Mechanic Career Guide