Complete Guide to Vehicle Modification Laws in Vermont
Vermont maintains a detailed set of vehicle equipment standards enforced through periodic inspection and its motor vehicle statutes. This guide breaks down the most common modifications enthusiasts ask about, from lowering and lift kits to window tint and lighting. The figures in this guide were verified against primary statute text (September 2026), so you can treat these numbers as accurate as of that check.
Lowering
Status: Conditional
Vermont does not set a minimum ride height or clearance rule for ordinary passenger cars, but it does cap bumper height at a maximum of 22 inches front and 22 inches rear. If you're lowering a special-category vehicle — a street rod, homebuilt, exhibition vehicle, or neighborhood electric vehicle (NEV) — a rim-line scrub test applies, and this scrub line requirement applies only to those special vehicle categories, not to ordinary cars.
For trucks, maximum bumper heights scale by weight: 24/26 in for vehicles up to 4,500 lb, 27/29 in for 4,501–7,500 lb, 28/30 in for 7,501 lb and over, and 28/31 in for 4WD and dual-wheel trucks.
This is governed under the Vermont DMV VN-113 Periodic Inspection Manual. Check the full lowering laws page for details.
Underglow
Status: Conditional
Vermont law bars operating a vehicle with a blue light of any kind, or any emergency warning lamp, without a permit. Non-emergency lamps that flash in any color other than amber are also banned. Steady accent lighting in permitted colors isn't expressly prohibited, but red or blue displays will fail inspection without a § 1253 permit.
Key limits: no blue of any kind is allowed without a permit; red requires a permit and is standard only at the rear; flashing in any color other than amber is prohibited; and reflector-equipped devices over 4 candlepower need Commissioner approval during lighting hours.
Exceptions: underglow lighting must avoid red, blue, or flashing displays; red lights are restricted to the rear of the vehicle only; blue is reserved for emergency vehicles; and flashing is prohibited except for turn signals and hazard lights.
This falls under 23 V.S.A. §§ 1251, 1254, 1246, and 1253. See the underglow laws page for the full picture.
Aftermarket Exhaust
Status: Conditional
Replacing your exhaust system is legal in Vermont, but a muffler in good working order is required, and cutouts or bypasses are prohibited. There's no statutory "no louder than stock" rule — instead, the standard is that the exhaust must not produce excessive or unusual noise.
Exceptions and requirements: you need a functioning muffler that prevents excessive noise, catalytic converters are required for vehicles originally equipped with them (removal is prohibited under federal law), straight pipes or bypasses aren't allowed, and general sound level restrictions apply.
This is addressed under 23 V.S.A. §§ 1221 and 1222. Full details are on the aftermarket exhaust laws page.
Wheel & Tire Protrusion
Status: Conditional
Vermont's inspection process will fail a vehicle if any fender has been removed, or if a fender fails to cover the tread portion of a tire. For modified vehicles specifically, fenders must cover the entire tire tread width from 15 degrees forward to 75 degrees rearward of the wheel centerline.
This standard comes from Code Vt. R. 14-050-022 (the VN-113 inspection manual) and 23 V.S.A. § 1306. Read more on the wheel & tire protrusion laws page.
Light Bars & LED Lighting
Status: Conditional
Vermont applies what may be the strictest lighting approval threshold in the country: no lighting device over 4 candlepower equipped with a reflector may be used on a highway unless the Commissioner has approved the device, its lens, and its candlepower.
Beam requirements: the beam must not rise more than 6 inches above bulb height at 75 feet, and must never rise more than 42 inches above the road surface. No cover is required for these devices.
This is governed under 23 V.S.A. §§ 1246 and 1243. Visit the light bars & LED lighting laws page for more.
License Plate Frames
Status: Conditional
Plates in Vermont must remain entirely unobscured, with numerals and letters plainly legible at all times. This "entirely unobscured" standard extends to the word VERMONT and the state slogan, meaning ordinary dealer frames that cover the top or bottom border would violate the law. Plate covers are not allowed, and the entire plate — including the state name and slogan — must stay visible.
Frames themselves are permitted, but only if they don't obscure any part of the plate, including numbers, letters, or state identification.
This falls under 23 V.S.A. § 511(a). See the license plate frame laws page for specifics.
Window Tint
Status: Conditional
Vermont takes a strict approach on front windows: no aftermarket tint is permitted on the front side windows at all. For the rear side windows and back window, any darkness level is allowed.
One important exception: any rear tint darkness requires exterior mirrors on both sides of the vehicle.
This is codified under 23 V.S.A. § 1125. Full details are on the window tint laws page.
Headlight & Taillight Tint
Status: Illegal
Smoked or tinted film on headlights and taillights is illegal in Vermont. No film is permitted on these lights at all. Headlights must emit white light, and taillights must show red at the required visibility distance — tinting that dims or discolors either violates these requirements.
This is enforced under 23 V.S.A. §§ 1243, 1247, and 1248. See the headlight & taillight tint laws page for more.
Lift Kits
Status: Conditional
Vermont caps bumper height at 22 inches front and 22 inches rear for pleasure cars. For trucks and multipurpose vehicles, the maximum rises by weight class: 24/26 in up to 4,500 lb, 27/29 in for 4,501–7,500 lb, 28/30 in for 7,501–10,000 lb, and 28/31 in for four-wheel-drive and dual-wheel trucks. Notably, there is no numeric suspension-lift limit — the restriction is on resulting bumper height, not lift height itself.
This is set out in the Vermont DMV VN-113 Periodic Inspection Manual, adopted under 23 V.S.A. § 1222 and Code Vt. R. 14-050-022. Full figures are on the lift kits laws page.
Exhaust Noise
Status: Conditional
Vermont sets no statewide decibel limit for passenger cars. That said, a muffler in good working order is still required, exhaust may not produce excessive or unusual noise, and cutouts or bypasses remain prohibited.
This is addressed under 23 V.S.A. § 1221, with "properly equipped" defined at § 4(37). See the exhaust noise laws page for details.
Window Banners
Status: Illegal
Vermont's windshield rules are tight: no material may be painted or adhered onto or over any transparent part of the windshield except enumerated items — a lower-right-corner area up to 4 by 12 inches, an upper-left-corner area up to 2 by 2.5 inches, required stickers, and transponders. There is no top-strip banner allowance, and a printed windshield banner is not legal in Vermont.
This is governed under 23 V.S.A. § 1125. Full details are on the window banners laws page.
Every modification above links to its full law page with exact limits, statute citations, and exceptions — or browse every Vermont mod law in one place, free.
This guide is for informational purposes only. Data is AI-extracted from public statutes and may contain errors. Always verify with local authorities.