Complete Guide to Vehicle Modification Laws in Oregon
Oregon enthusiasts have a lot of freedom to customize their rides, but state law still sets clear boundaries on lighting, tint, exhaust, ride height, and more. This guide breaks down what's allowed, what's restricted, and what's outright banned under Oregon statute. All figures below were verified against primary statute text (September 2026), so you can plan your build with confidence.
Underglow
Status: Conditional
Underglow lighting is legal in Oregon, and you can run it while driving — but color and behavior are restricted. The rules: no red visible from the front, blue is reserved for police, and no flashing or strobe effects are permitted.
Specifically, no red light may be visible from directly in front of the vehicle, blue is off-limits to civilians since it's reserved for police vehicles, and flashing is prohibited except for standard signals. Rear-mounted lighting must show red. General lighting equipment standards are codified throughout ORS chapter 816.
Statute: ORS 816.350, 816.360. See the full underglow laws page for details.
Wheel & Tire Protrusion
Status: Conditional
Oregon requires Type III fenders or mudguards on each axle of a passenger car. These fenders must extend the full width over the tire, running from above and forward of the tire's center down to within 27 inches of the highway. There is no separate protrusion limit beyond this fender coverage requirement.
Statute: ORS 815.182, with specifications under ORS 815.180(2)(c) and exemptions under ORS 815.190. Learn more at the wheel and tire protrusion laws page.
Headlight & Taillight Tint
Status: Illegal
Smoked or tinted film on headlights and taillights is not permitted in Oregon. Headlights must emit white light, and taillights must show red at the required visibility distance. Any tint that dims the output or shifts the color violates these requirements — Oregon law prohibits any tinting, covering, or alteration that reduces light output or changes color from white/amber.
Statute: ORS 816.050, 816.080, 816.350. Full details at the headlight and taillight tint laws page.
License Plate Frames
Status: Conditional
Frames and plate holders are allowed, but they cannot obscure the numbers, letters, or registration stickers, and nothing may be placed on the plate that alters its color, configuration, numbers, letters, or material. Covers that fall under this alteration clause are not allowed.
The key requirement is that numbers, letters, and registration stickers must remain fully visible at all times, including any state identification. Clear covers are generally acceptable as long as they don't cause glare or obstruction.
Statute: ORS 803.550. See the license plate frame laws page for the complete rule.
Window Banners
Status: Conditional
Oregon allows tinting material only on the top 6 inches of the windshield and no other portion — the state measures this in inches rather than using an AS-1 line reference. Because this material must be transparent, a printed or opaque banner is not legal in Oregon; only a clear tint band along that top strip is allowed.
The banner or strip must sit at the top of the windshield, must not extend below 6 inches from the top (or the AS-1 line, whichever is lower), and must not obstruct the driver's view.
Statute: ORS 815.221(3), with obstruction rules under ORS 815.220. Check the window banner laws page for more.
Lift Kits
Status: Legal
Good news for truck and off-road builders: Oregon sets no statewide lift, frame-height, or bumper-height limit. The only real ceiling is the overall vehicle height cap of 14 feet. General equipment rules — like proper headlamp height and functioning lighting — still apply regardless of lift height.
Statute: ORS 818.080, with clearance rules under ORS 815.245. Full specifics at the lift kit laws page.
Lowering
Status: Conditional
If you're lowering your ride, Oregon applies a rim-line test: no part of a passenger vehicle other than the wheels may have less ground clearance than the lowest point of any wheel rim in contact with the road. In other words, your frame, body, or components can't sit lower than your wheel rims.
Statute: ORS 815.245. See the lowering laws page for the full standard.
Exhaust Noise
Status: Conditional
Oregon caps passenger-car exhaust noise using a stationary test at 25 feet under DEQ procedures. The limits are 94 dBA for pre-1976 vehicles and 91 dBA for 1976 and newer vehicles. Other vehicle categories fall under 92/88 dBA limits.
Statute: ORS 815.250. Full breakdown at the exhaust noise laws page.
Light Bars & LED Lighting
Status: Conditional
Oregon requires no cover on auxiliary lighting. Lights used on the highway must be mounted 54 inches or less above the road surface and must show white light forward. Anything mounted higher than 54 inches may not be lighted while on a highway.
Statute: ORS 816.060, with related provisions in ORS 816.350 and 811.515. See the light bar and LED lighting laws page for more.
Window Tint
Status: Conditional
Oregon's baseline tint rule applies 35% VLT minimum across the board: front side windows, rear side windows, and the back window all require at least 35% VLT.
This differs by vehicle type: for SUVs, trucks, and vans, front side windows still require a minimum 35% VLT, but these multi-purpose vehicles (MPVs) may use darker glass behind the driver as long as the vehicle has exterior mirrors on both sides.
Statute: ORS 815.221. Full details at the window tint laws page.
Aftermarket Exhaust
Status: Conditional
Swapping out your exhaust system is legal in Oregon, but a muffler in good working order is required, and cutouts or bypasses are prohibited. Notably, Oregon has no statutory "no louder than stock" rule — instead, the standard is that your exhaust must not produce excessive or unusual noise. Separately, removing a catalytic converter is prohibited under federal law.
Statute: ORS 815.250, with pollution-control equipment addressed in ORS 815.305. See the aftermarket exhaust laws page for the complete picture.
Every modification above links to its full law page with exact limits, statute citations, and exceptions — or browse every Oregon mod law in one place, free.
Disclaimer: This guide is for informational purposes only. Data is AI-extracted from public statutes and may contain errors. Always verify with local authorities.