Aftermarket Exhaust in Kentucky
Replacing the exhaust system is legal in Kentucky, but a muffler in good working order is required and cutouts or bypasses are prohibited. Modifications that make the exhaust louder than the originally installed muffler are prohibited.
Verified against primary sources · August 2026
What the law says
Replacing the exhaust system is legal in Kentucky, but a muffler in good working order is required and cutouts or bypasses are prohibited. Modifications that make the exhaust louder than the originally installed muffler are prohibited. Removing the catalytic converter is prohibited by federal law (Clean Air Act § 203) regardless of state rules. Kentucky has no state vehicle inspection.
Specific Limits
- Cutouts
- prohibited
- Muffler required
- Yes
- Catalytic converter
- removal prohibited by federal law
Exceptions & Exemptions
Exhaust system must not exceed noise levels that disturb the peace. Muffler must be in good working order and cannot be bypassed. Catalytic converter removal is prohibited on vehicles originally equipped with them.
Frequently Asked Questions
Are aftermarket exhaust legal in Kentucky?
What are the exact aftermarket exhaust limits in Kentucky?
Are there exceptions for aftermarket exhaust in Kentucky?
Street-legal aftermarket exhaust picks
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