Aftermarket Exhaust in South Dakota
Replacing the exhaust system is legal in South Dakota, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise.
Verified against primary sources · August 2026
What the law says
Replacing the exhaust system is legal in South Dakota, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise. Removing the catalytic converter is prohibited by federal law (Clean Air Act § 203) regardless of state rules. South Dakota does require both an exhaust system and a muffler — the earlier claim that no statute existed was wrong. Exhaust must discharge to the rear or rearward of the side windows. A violation is a Class 2 misdemeanor.
Specific Limits
- Cutouts
- prohibited
- Muffler required
- Yes
- Louder than stock
- not addressed; excessive noise standard applies
- Catalytic converter
- removal prohibited by federal law
Exceptions & Exemptions
No specific South Dakota statute found regarding aftermarket exhaust modifications
Frequently Asked Questions
Are aftermarket exhaust legal in South Dakota?
What are the exact aftermarket exhaust limits in South Dakota?
Are there exceptions for aftermarket exhaust in South Dakota?
Street-legal aftermarket exhaust picks
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