What Is the Red Seal Pass Rate? And How to Beat the Odds
Heavy Duty Equipment Technician Red Seal Exam: The Complete Guide
ASE T2 Diesel Engine Exam: What Technicians Need to Know
The ASE T2 certification is the industry standard for diesel engine technicians working on medium and heavy trucks in the United States. If you work on heavy equipment rather than highway trucks, the Red Seal Heavy Duty Equipment Technician certification covers a broader scope — see our guide to the Heavy Duty Equipment Technician Red Seal exam.
The Exam Format
60–65 multiple-choice questions. Approximately 90 minutes. Scaled scoring with a threshold around 70%. Computer-based at Prometric centres. ASE recommends 3 years of hands-on experience. Certification valid for 5 years.
The Six Task Areas
1. General Engine Diagnosis (~15%). Abnormal noises, excessive smoke (white, black, blue), vibrations, loss of power, hard starting, no-start conditions.
2. Cylinder Head and Valve Train (~17%). Head inspection, valve guides, seats, springs, rocker arms, camshafts, injector sleeves, torque sequences.
3. Engine Block (~17%). Crankshaft, bearings, pistons, rings, cylinder liners, oil pan.
4. Lubrication and Cooling Systems (~17%). Oil pump, oil cooler, thermostat, water pump, coolant analysis (SCA levels), pressure testing, fans.
5. Air Induction and Exhaust Systems (~17%). Turbocharger, intercooler, intake/exhaust manifolds, DPF regeneration, SCR systems, DEF, EGR.
6. Engine Brakes (~17%). Jake brakes (compression release), exhaust brakes, hydraulic retarders.
Where Candidates Struggle
Modern emissions systems (DPF, SCR, DEF). Platform-specific vs brand-agnostic knowledge. SCA concentration values.
The ASE T2 Diesel Engines Exam Prep book gives you 520 ASE-style practice questions across 8 full-length tests.
[Get the ASE T2 Exam Prep book on Amazon →]
[See the full ASE T2 trade page → /ase-t2-diesel-engines/]
Frequently Asked Questions
How many questions?
60–65 multiple-choice, approximately 90 minutes.
How long is certification valid?
5 years. You must retest to maintain it.
Can I take just T2?
Yes. Each ASE test is standalone. To earn ASE Master Medium/Heavy Truck Technician, you need all eight T-series tests (T1–T8).
