Stockton, CA Noise Ordinances: Vehicle Noise (2026)

California Vehicle Code § 27150 requires every motor vehicle with an internal-combustion engine to have an adequate muffler in constant operation, and prohibits any cutout, bypass, or similar device. Cal. VC §§ 27201–27207 set the dBA noise limits measured at 50 feet from the centerline of the vehicle: motorcycles range from 92 dBA (pre-1970) down to 80 dBA (1986 and later); other motor vehicles range from 86 dBA (pre-1973) to 80 dBA (1975 and later); heavy vehicles over the federal GVWR thresholds are capped at 80–88 dBA depending on year (§ 27204); governed engines over 10,000 lb are capped at 88 dBA (§ 27207). Cal. VC § 27202.1 requires post-2013 motorcycles and aftermarket motorcycle exhaust systems to carry the EPA exhaust-system label. Stockton Police Department enforces these state limits on city streets under the California Vehicle Code; the Stockton Municipal Code (Title 10 — Vehicles and Traffic) adds local provisions on horn use, parking, and engine braking but cannot set vehicle-noise dBA limits that conflict with the state-preempted Vehicle Code framework.