La Grange, MO Noise Ordinances: Vehicle Noise (2026)

Section 340.230 makes it unlawful to cause excessive loud noises from a motor vehicle on the streets of LaGrange, naming three triggers: screeching tires from sudden starts, stops or turns; running the engine at excessive speeds while not in motion so as to cause excessive exhaust or muffler noise; or any other use of a motor vehicle causing excessive noise. The Code defines "excessive noise" as noise that would generally result in discomfort to the public, a public-nuisance style standard rather than a decibel meter reading, so enforcement turns on what a reasonable neighbor finds disruptive.

Section 370.140.B separately targets the equipment itself: muffler cutouts are banned outright, no vehicle may be driven so as to make excessive and unnecessary noise from its machinery, motor, signaling device or improperly loaded cargo, and every motor vehicle must carry a properly attached muffler built to quiet exhaust noise as completely as a modern gas engine passenger car. Any cutout or opening in the exhaust pipe between the motor and the muffler must be fully closed and disconnected from its operating lever so it cannot be opened while the vehicle is moving. The Police Department enforces both sections on the streets of the City of LaGrange.