ASE T3 Drive Train practice test
The T3 test covers the truck driveline: heavy-duty clutches, non-synchronized manual transmissions, automated manuals, driveshafts, and single or tandem drive axles with power dividers. Required for Master Truck status.
During a truck axle rebuild, the drive-side tooth contact pattern sits deep in the flank (toward the root, near the toe). The standard correction is to:
How the T3 test works
40 scored questions
+ ~10 unscored research questions
60 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 T3 test covers
The official task list for T3 Drive Train (Medium-Heavy Truck) breaks down into these content areas — the practice bank above draws from all of them:
- Heavy-duty clutches — adjustment, release systems, dual-plate designs
- Manual and automated manual transmissions — non-synchronized shifting, air shift systems
- Driveshafts and universal joints — angles, phasing, guards
- Drive axles — single and tandem, interaxle differential (power divider), lockouts
- PTO and auxiliary drive basics
Frequently asked
- How many questions are on the ASE T3 test?
- The T3 test has 40 scored questions plus about 10 unscored research questions, with a 60-minute time limit.
- Does T3 cover automated manual transmissions?
- Modern task lists include automated manual transmissions alongside traditional non-synchronized gearboxes — check the current ASE study guide for the exact breakdown.
- What is a power divider?
- The interaxle differential on a tandem-axle tractor. It splits torque between the two rear axles and can be locked out for traction — a frequent T3 topic.
Other ASE practice tests
Driving trucks, not just wrenching on them?
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