ASE T1 Gasoline Engines practice test
The T1 test covers gasoline engines in medium and heavy trucks: mechanical diagnosis and repair plus the fuel, ignition, and emissions systems that keep them running under commercial duty cycles. Optional for Master Truck status.
A gasoline flatbed clunks on throttle tip-in and tip-out, and the engine can be seen lifting excessively during a power-brake test. The MOST likely cause is:
How the T1 test works
50 scored questions
+ ~10 unscored research questions
75 minutes
computer-based, at a test center
$62 per test
plus one $34 registration fee per order
Valid 5 years
then a shorter recertification test
ASE does not publish a fixed passing percentage — scores are scaled. Around 65–70% correct is the commonly cited range; aim above 80% in practice so you walk in with margin. The certificate is issued once ASE verifies your required work experience.
What the T1 test covers
The official task list for T1 Gasoline Engines (Medium-Heavy Truck) breaks down into these content areas — the practice bank above draws from all of them:
- General engine diagnosis — noises, smoke, leaks, compression and vacuum testing
- Cylinder head and valve train service
- Engine block — pistons, rings, crankshaft, bearings
- Lubrication and cooling systems
- Fuel, ignition, and exhaust systems under truck duty cycles
Frequently asked
- How many questions are on the ASE T1 test?
- The T1 test has 50 scored questions plus about 10 unscored research questions, with a 75-minute time limit.
- Is T1 required for Master Medium-Heavy Truck Technician status?
- No — Master Truck status requires T2 through T8. T1 is an optional additional certification.
- How does T1 differ from the A1 test?
- The mechanical fundamentals overlap heavily, but T1 is framed around medium/heavy truck engines, duty cycles, and service practices rather than passenger cars.
Other ASE practice tests
Driving trucks, not just wrenching on them?
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