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Colorado Exhaust & Muffler Laws (2026)

Info: Your vehicle needs an adequate muffler. A cutoff or bypass (which routes exhaust around the muffler) is prohibited, and so is any exhaust change that raises noise above the stock level.

InfoVerified Jul 22, 2026

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Your vehicle needs an adequate muffler. A cutoff or bypass (which routes exhaust around the muffler) is prohibited, and so is any exhaust change that raises noise above the stock level. Colorado sets no fixed decibel limit for passenger cars (C.R.S. § 42-4-225).

Official source: leg.colorado.gov →

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