Merced County, CA Noise Ordinances: Vehicle Noise (2026)

Vehicle noise in unincorporated Merced County splits between local off-road rules and state on-road rules. Under Chapter 10.60 of the County Code, Section 10.60.040 makes it unlawful to use, operate, or permit the operation of one or more off-highway vehicles on private property such that the resulting sound creates a noise disturbance across a residential real property line. This covers dirt bikes, ATVs, and similar recreational vehicles ridden on rural parcels near homes. The chapter also exempts off-highway vehicles operated on public lands away from highways (Section 10.60.050). For street-legal vehicles on public roads, the County relies on the California Vehicle Code rather than a local decibel ordinance: Vehicle Code Section 27150 requires every motor vehicle to have an adequate muffler in good working order, and Section 27151 prohibits modified or cut-out exhaust systems that amplify noise. California Vehicle Code Section 23130 sets statewide roadside vehicle noise limits measured at 50 feet. These state provisions are enforced by the Merced County Sheriff and the California Highway Patrol. Local Chapter 10.60 violations are handled through the general penalty scheme in Chapter 1.28.