No, Missouri prohibits exhaust systems emitting excessive noise under Revised Statutes §307.390, with local jurisdictions like St. Louis and Kansas City enforcing stricter decibel limits. Modified exhausts exceeding 92 decibels risk citations, and 2026 compliance mandates tamper-evident compliance stickers for aftermarket systems.
Key Regulations for Loud Exhausts in Missouri
- State Statute Enforcement: §307.390 criminalizes exhaust noise exceeding 92 dB(A) during stationary or moving tests, with penalties escalating to misdemeanor charges for repeat offenses.
- Local Ordinance Variations: Cities like St. Louis cap exhaust noise at 88 dB(A) for vehicles under 10,000 lbs, while Kansas City’s 2024 ordinance requires annual decibel certification for modified systems.
- 2026 Compliance Mandates: New state regulations will mandate tamper-evident compliance stickers for aftermarket exhausts, with inspections conducted during annual vehicle safety checks.
Local law enforcement agencies, including the Missouri State Highway Patrol, prioritize noise violations in urban corridors, particularly near residential zones. Failure to comply may result in fines up to $2,000 or vehicle impoundment for repeat violations. Exemptions exist for emergency vehicles and certain agricultural equipment, but standard passenger vehicles must adhere to statewide noise thresholds.