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Unlawful Vehicle Modifications

Whether subtle or drastic, some vehicle modifications are illegal. Certain modifications are less obvious, like a window tint. Other customizations, such as a loud exhaust system or custom lighting, are hard to miss and can be easily heard or seen on public roads.

Under traffic laws in most states, you can receive a traffic ticket for modifications violating laws regulating vehicle specifications and equipment.

Examples of motor vehicle modifications that could result in a citation include:

  • Addition of non-standard lighting, like underglow neon lights, under-vehicle lights, or blue lights
  • Alteration or removal of air pollution and emissions control device
  • Modification of vehicle ground clearance on lowered or raised vehicles
  • Removal of mufflers and other sound-control devices
  • Aftermarket exhaust systems
  • Window tinting on the windshield, driver/front passenger side windows, or rear windows
  • Addition of radar detectors or radar jammers
  • Diesel truck engine modifications that burn excessive fuel or the “rolling coal" effect
  • Automatic license plate covers
  • Nitrous Oxide System (NOS): While these are typically legal on a racetrack or off-road, most states forbid use on any public roads or highways

Stock vs. Modified Vehicles

"Stock" and "modified" are terms commonly used to describe the state of a vehicle. They characterize the extent a vehicle has been altered from its original factory specifications.

  • stock vehicle is in its original condition as it came from the factory. It has not undergone any significant modifications. Stock vehicles typically meet the safety, emissions, and legal standards set by the manufacturer and relevant authorities. They are also generally covered by manufacturer warranties.
  • modified vehicle has undergone modification or upgrades beyond its original specifications. Depending on the specific modifications, a modified vehicle may no longer meet factory standards, including safety, emissions, or legal requirements. It may also be unlawful under state law. Modifications may also void some manufacturer warranties.

What Police Look For

If you have modified your car, it may give an officer a valid excuse to pull you over. There are several modifications that officers look for on public roadways:

Most officers are looking for:

  • Sound and noise level modifications, like exhaust over 95 decibels
  • Frame and suspension mods
  • Engine modifications
  • Aftermarket lighting
  • Window tinting

Traffic laws vary from state to state, but those listed above are the most typical.

The easiest way to avoid the police for this issue is to not modify your car. However, if you are cited for an unlawful modification, you may be able to remedy the situation. Read on to learn more.

Penalties for Unlawful Vehicle Modifications

Car owners can receive a mechanical violation traffic ticket for an unlawfully modified vehicle. In some states, citations for certain unlawful vehicle modifications are considered "fix-it" tickets or "correctable violations."

In California, for example, if you are given a fix-it ticket by a police officer, "yes" will be checked next to Correctable Violation. After the problem is fixed, like removing illegal under-car lights, you must get the signature of an authorized person such as a local law enforcement officer on the Certificate of Correction portion of the ticket.

If you are issued a fix-it ticket for an unlawful vehicle modification in your state, read the ticket to determine whether you can mail the proof of correction, rather than taking it to court.

If the court accepts your correction, the case will be dismissed. If you fail to fix the problem quickly after receiving a fix-it ticket, you will need to pay the fine. You may also be issued another ticket, which can go on your driving record.

Separate Potential Penalties

Even if a vehicle modification is legal, driving with questionable vehicle modifications may result in separate legal charges.

For example, if you installed smoked taillights on your car, it might give a law enforcement reason to pull you over. If you happened to be driving over the speed limit, the officer could write you a ticket for speeding even if they could not legally ticket you for your taillight tint.

Unlawful Vehicle Modifications and State Laws

Different states have varying levels of regulation for car modifications. Check the specific laws in your state before making any custom modifications to your vehicle. Car modification laws can also change over time. Staying informed about the latest regulations is key to avoiding legal issues.

California is known for having the strictest car modification laws. The California Air Resources Board (CARB) oversees controlling and limiting air pollution.

CARB closely monitors “aftermarket" parts (parts not originally manufactured by the vehicle's original equipment manufacturer) before approving what will be installed on any vehicle. This applies to exhaust systems, cold-air intake, or other modifications that may affect fuel economy or emissions.

Other states known for strictly regulating car modifications include:

  • New York
  • New Jersey
  • Massachusetts
  • Pennsylvania
  • Texas
  • Washington
  • Oregon
  • Illinois

Conversely, states with less regulation for car modifications include:

  • Mississippi
  • South Dakota
  • Wyoming
  • Missouri
  • Arizona
  • Idaho

While these states may have more lenient regulations, they may still require certain safety and equipment standards.

Car Modification Violation? Get an Attorney's Help

Consider your options if you've been cited for illegal car modifications. Consult an experienced traffic ticket attorney in your area to learn if your case is worth fighting.

A skilled attorney familiar with your area's laws can evaluate your ticket's circumstances and potentially save you a costly fine.

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