Whether you live in Kentucky or are moving to the area, you need to know what vehicle modifications are permitted so that your car or truck is street legal. The information below will help you make sure your vehicle is in compliance with the Kentucky laws.
Sounds and noise
Kentucky has sound regulations that affect the sound system and muffler on your vehicles.
- Sound can’t emit from your vehicle or property that unreasonably interferes with others and their enjoyment or ability to do business. There are not set limits as to how loud this may be.
Mufflers are required when driving a vehicle on the highway.
Mufflers with cutouts are not permitted on the highway.
Vehicles used on and off highway can’t have modified exhaust systems that amplify the sound beyond that of the original manufacturer.
Tip: Also check with local county laws in Kentucky to make sure you are following any municipal noise ordinances that may be more stringent than state-level laws.
Frame and suspension
Kentucky does not place any limits on suspension lifts, frame lifts or bumper heights, but vehicles can’t be taller than 11 feet 6 inches.
Kentucky does not require emissions testing and currently has no laws concerning engine modifications or swaps.
Lighting and windows
No flashing lights are permitted on passenger vehicles other than amber hazard lights.
No colored (red, green, yellow or similar) flashing lights can be used within 100 feet of highways maintained by the state.
Non-reflective tint can be applied to the top of the windshield above the AS-1 line from the manufacturer.
Front side windows must allow over 35% of light through.
Back side and rear windows must allow over 18% of light through.
Front side and back side window tint can’t be over 25% reflective.
Legal tinting identification sticker must be affixed to the doorjamb on the driver’s door.
Antique/classic car modifications
Kentucky also has regulations for classic or antique vehicles.
Antique vehicles that are 25 or more years old qualify for a historic plate.
Historic vehicles are not used for daily transportation, but are used for tours, parades, and exhibitions.
If you want to make vehicle modifications but you want to ensure they follow Kentucky law, YourMechanic can provide the mobile mechanics to help you install the new parts. You can also ask our mechanics what modifications may be best suited to your car using our free online Q&A system, Ask a Mechanic.
This article originally appeared on YourMechanic.com as The Guide to Legal Car Modifications in Kentucky and was authored by Valerie Johnston.