All 45 exams / T-series / ASE T4 Brakes
T4
ASE T4 Brakes
Medium and heavy trucks
What's on the T4 exam?
1
Air Brakes Diagnosis and Repair
2
Hydraulic Brakes Diagnosis and Repair
3
Antilock Brake System (ABS), Automatic Traction Control (ATC), Electronic Stability Control System, and Collision Warning/Avoidance System Diagnosis and Repair
Content-area outline only, authored from ASE's public task-list structure. No test question, answer, or diagnostic scenario is reproduced from ASE or any prep publisher.
T4 quick reference T-series
Categoryrepair technician
Work experience2
Question count60
Time allowed75 minutes
Fee$62
Recert cycle5 years
Recert pathRetest (approximately half-length recert version) every 5 years, or the ASE Renewal App.
Source: https://ase.com/wp-content/uploads/ASE_MedHeavyTruck_Study_Guide.pdf.
Checked 2026-07-30.
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