No, Wisconsin prohibits exhaust systems producing excessive noise under Wis. Stat. § 347.45, enforced by the Wisconsin State Patrol and local law enforcement. Modified exhausts exceeding 92 decibels (dB) measured at 20 feet are illegal, with stricter local ordinances possible. Violations may result in fines up to $200 and muffler removal orders.
Key Regulations for Loud Exhausts in Wisconsin
- Decibel Limits: State law caps exhaust noise at 92 dB when measured 20 feet from the vehicle, aligning with SAE J1169 standards. Local municipalities, such as Milwaukee and Madison, may impose stricter limits (e.g., 88 dB in some zones).
- Muffler Requirements: All vehicles must have a functioning muffler or exhaust system that prevents excessive noise or smoke. Removal of factory mufflers or installation of “straight pipes” violates § 347.45(1).
- Enforcement & Penalties: The Wisconsin State Patrol conducts routine noise compliance checks, particularly in urban areas. First-time offenders face fines up to $200, while repeat violations may lead to muffler replacement orders or vehicle impoundment.
Local ordinances, such as Madison’s noise control code (Sec. 23.08), further restrict exhaust noise in residential neighborhoods during nighttime hours (10 PM–7 AM). Vehicles modified for racing or off-road use are exempt only if operated on private property. Compliance with federal EPA noise standards (40 CFR Part 205) is also required for aftermarket exhaust systems.