---
kind: "unit"
title: "49"
title_heading: "Transportation"
key: "subtB/chV/part523"
level: "part"
label: "Part 523"
heading: "Vehicle Classification"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/49/subtB-chV-part523"
sections_count: 10
---

# Part 523 — Vehicle Classification

Title 49 C.F.R. — Transportation › Subtitle B — Other Regulations Relating to Transportation › Chapter V — National Highway Traffic Safety Administration, Department of Transportation

## Sections

- [§523.1. Scope.](/cfr/49/523.1.md)
- [§523.2. Definitions.](/cfr/49/523.2.md)
- [§523.3. Automobile.](/cfr/49/523.3.md)
- [§523.4. Passenger automobile.](/cfr/49/523.4.md)
- [§523.5. Non-passenger automobile.](/cfr/49/523.5.md)
- [§523.6. Heavy-duty vehicle.](/cfr/49/523.6.md)
- [§523.7. Heavy-duty pickup trucks and vans.](/cfr/49/523.7.md)
- [§523.8. Heavy-duty vocational vehicle.](/cfr/49/523.8.md)
- [§523.9. Truck tractors.](/cfr/49/523.9.md)
- [§523.10. Heavy-duty trailers.](/cfr/49/523.10.md)