← Mississippi driving laws›Exhaust & Muffler

Mississippi Exhaust & Muffler Laws (2026)

Info: Every vehicle needs a muffler in good working order, running at all times, so it doesn't make excessive or unusual noise or annoying smoke, and no one may use a muffler cutout, bypass or similar device (which routes exhaust around the muffler) on a highway.

InfoVerified Jul 30, 2026

Vehicle rules change at the state line.Track them in the free LawLert iPhone app and get an alert when you cross into a state where they differ. No account.Get the app

Every vehicle needs a muffler in good working order, running at all times, so it doesn't make excessive or unusual noise or annoying smoke, and no one may use a muffler cutout, bypass or similar device (which routes exhaust around the muffler) on a highway. See Miss. Code § 63-7-55. Mississippi sets no decibel number. Violations of Title 63, Chapter 7 are misdemeanors (§ 63-9-11).

Official source: driverservicebureau.dps.ms.gov →

General legal information, not legal advice — verify important decisions with a licensed attorney.

Don't get caught off guardCross into a state where this law is different and the free iPhone app tells you what changed, even with the app closed. It also alerts you when a law you track changes where you live. No account.Get the free app

Track this law — get alerted when it changes

We watch the official sources behind Mississippi vehicle rules. If a tracked rule changes, you get one short email — never more than one a week. Free, unsubscribe anytime.