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California Exhaust & Muffler Laws (2026)

Info: Your vehicle needs an adequate muffler, and you can't run a cutout or bypass (which routes exhaust around the muffler).

InfoVerified Jun 19, 2026
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Your vehicle needs an adequate muffler, and you can't run a cutout or bypass (which routes exhaust around the muffler). Vehicles under 6,000 pounds are capped at 95 decibels, measured by the SAE J1169 test. Any aftermarket exhaust has to be legal under California Air Resources Board (CARB) rules (Cal. Veh. Code §§ 27150-27151, 27156).

Official source: leginfo.legislature.ca.gov →

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