Car Accessories And The Law – Are Your Mods Legal?

Car Accessories And The Law - Featured Image

If you’re a car fanatic, you’ve probably tricked out your ride in a myriad number of ways. So long as you hang around your neighborhood, you probably already have a good idea about which of your mods are legal and which will cause the police to give you grief.

But the laws regarding car mods vary substantially from state to state. What’s kosher in one state might be illegal in the one that you’re driving to for a weekend visit. In this article, we’ll teach you about a few of the most common car mods which are problematic for obeying the law.

Window Tinting

Window tinting is the most notorious legal liability when it comes to your car. Many states have laws which stipulate that certain shades are not allowed, but lighter shades are. Likewise, many states require the windshield to be without tint, but the driver’s side window can be tinted.

But other states prohibit the driver’s side window from being tinted. The easiest way to avoid these issues entirely is to avoid any tinting whatsoever, but that might be difficult if you live somewhere with an abundance of sun.

So, there’s a second-best option – which you might not like. Your chances are the most favorable if you stick to tinting your rear passenger side and driver side windows only.

It’ll be unsightly, but there will be a very low chance of you getting pulled over for disobeying the law when it’s clear that the driver has a full range of unimpeded view.

If you have removable tints, it might make sense to take them off before you travel into a new state – or maybe look up your state’s laws on window tints.

Suspension Modifications

Suspension modifications can be a lot of fun, but the police may not take to them. While suspension modifications which allow your car to rise or drop may be legal in many places, they are also illegal in many places.

If you can conceal them by riding your car at a normal height while on the go, you shouldn’t have a problem. It’s only if you are driving with your car in a different configuration of its suspension system that you will get pulled over – provided that you aren’t pulled over for something unrelated.

Engine Emissions Modifications

Changes to your car’s catalytic converter or other engine parts can cause your car to violate emissions laws in your state.

This means that in some states, your car won’t pass inspection. Despite the atmosphere of the country being shared, not all states have the same laws when it comes to vehicle emissions.

While you could get away with blowing black smoke out of your exhaust pipes in some states, it’ll get you pulled over right away in others. Err on the side of safety by keeping your engine unmodified.

On the other hand, if you won’t be getting your car inspected in another state, you can probably drive your car with a modified engine without fear. Emissions modifications aren’t going to get caught in traffic stops or other casual encounters with the police, so you shouldn’t need to worry.

Headlight And Lighting Mods

Headlight mods and other lighting modifications are at high risk for being illegal, although you may have some flex if you merely possess the modification but refrain from using it.

Headlight mods include all manner of colors, extra lights, and differently angled lights. Generally, so long as these lights don’t interfere with other drivers on the road or prevent the unimpeded identification of your legally mandated light systems, you should be fine with these modifications.

Using them, however, might make you a target for law enforcement. This is especially true if your car has:

Once again, these lights are unlikely to get you into trouble until you start using them. The differences between state light laws are substantial, but, unlike other modifications, they shouldn’t prevent you from passing your inspection or passing through a casual stop with police without incident.

Sound Systems

You might think that sound systems are an odd item to appear on this list. After all, turn your sound down, and you won’t have any trouble. Unfortunately, things aren’t that simple.

Your car is a sealed environment, and so to you, it appears that sounds stay mostly confined to the inside so long as you keep the windows closed. Under ideal circumstances, your car’s sound system behaves exactly as you’d expect: sound stays on the inside.

Your car’s noise insulation may vary a lot depending on what kind of car you have, though. Even if the noise level sounds acceptable from the inside, it’s possible that your car has poor noise insulation, and most of the sound is reverberating outside of the car.

If the reverberating sound is louder than a certain decibel level, the police may have cause to pull you over in some states.

The exact decibel level will vary from state to state, but in general, you should be careful with after-market sound systems because they can often exceed the insulation tolerances of the car and leak a lot of noise.

Furthermore, any wacky aftermarket sound modifications like sirens, air horns, or megaphones may be illegal depending on the jurisdiction. These items may get you a citation whether or not you use them – but if you use them, you should expect some unwanted (or perhaps, wanted) attention.


Your muffler is responsible for keeping the noise level of your car’s engine at an acceptable level. Modified mufflers may sound like a lot of fun, but they’ll also attract the ire of police in many areas, depending on the exact modification.

If your muffler doesn’t substantially change your engine’s sound or noise level beyond normal, you’re probably fine, but you may not pass inspection, and you may get an extra citation at a traffic stop.

If your muffler is broadly divergent from the other cars on the road, you should expect to get pulled over promptly whether or not the modification is explicitly legal or illegal in any given state.

Once again, the laws vary a lot from state to state, so be sure to check before you travel.

Studded Tires

Though studded tires are a favorite of drivers in snowy climates, they’re illegal in many jurisdictions where their negative impact on the pavement might break the budget.

Studded tires tend to degrade the pavement faster than other forms of tires, even if they provide individual drivers with superior traction in the worst weather. If anyone notices, you’ll get pulled over promptly.

There are some states where studded tires are explicitly illegal, although in many others you may be able to get away with passing inspection nonetheless.

License Plate Frames

Ah, the license plate frame. Frames bring your license plate a bit of character, and they can spice up an otherwise boring portion of your car. Unfortunately, there are many laws regulating license plate frames which may or may not be used as an excuse for a traffic stop.

If your license plate frame has lights which differ from the mandated ones, they might be illegal. Likewise, if they obscure the license number in any way, they’re probably illegal.

No lights on the frame at all? In some places, that means it’s illegal. Off-center? Illegal.

Be very careful when modifying your license plate frame – it’s a seemingly harmless piece of your car to modify, but it’s one of the most likely to get you pulled over because it’s one of the first places that a police officer will look when they see your car.

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.