← Delaware driving laws›Exhaust & Muffler

Delaware Exhaust & Muffler Laws (2026)

Info: Your vehicle needs a muffler in good order, and muffler cutouts (which route exhaust around the muffler) are prohibited — it's also unlawful to sell a gutted muffler, a cutout, or straight pipe.

InfoVerified Jul 22, 2026

Vehicle rules change at the state line — and in your state.Track them in the free LawLert iPhone app: it alerts you when you cross into a state where they differ, and when they change in your state. No account.Get the app

Your vehicle needs a muffler in good order, and muffler cutouts (which route exhaust around the muffler) are prohibited — it's also unlawful to sell a gutted muffler, a cutout, or straight pipe. Delaware sets no fixed decibel limit (21 Del. C. § 4311).

Official source: delcode.delaware.gov →

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

Exhaust & Muffler in states bordering Delaware

The same rule in each neighboring state LawLert has verified, from that state’s own official source.

MarylandInfo
Your vehicle needs a muffler in good working order, and muffler cutouts and bypasses (which route exhaust around the muffler) are prohibited, as are tailpipe extensions that amplify noise. Maryland sets no fixed decibel limit (Md. Transp. § 22-402).
Verified Jun 19, 2026 · Source: mgaleg.maryland.gov · Full Maryland rule →
New JerseyInfo
Your vehicle needs a muffler in good working order, and cut-outs and bypasses (which route exhaust around the muffler) are prohibited while excessive or unusual noise is barred. New Jersey sets no fixed decibel limit (N.J. Stat. § 39:3-70).
Verified Jul 30, 2026 · Source: nj.gov · Full New Jersey rule →
PennsylvaniaInfo
Your vehicle needs a muffler. Cutouts, bypasses (which route exhaust around the muffler), and noise-amplifying changes are prohibited. Sound limits are set by Department regulation; the statute itself sets no fixed decibel number (75 Pa.C.S. § 4523).
Verified Jun 19, 2026 · Source: legis.state.pa.us · Full Pennsylvania rule →

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 Delaware vehicle rules. If a tracked rule changes, you get one short email — never more than one a week. Free, unsubscribe anytime.