We all like a lot of aftermarket items that are out there; however, before you install them, ensure they are not against the law. Retail stores can sell almost anything they want (as long as possession of it isn't illegal), but that doesn't mean it is legal for you to use on the public roadway.
The following is just a bit of information to questions that have been answered by the Texas Department of Public Safety
“Snake Eyes” – these are the lights that everyone sees on the hoods of modified vehicles and they are replacement windshield washer items. If these “snake eyes” are displaying white light, they are okay; however, if they are displaying any other color, they are against the law.
Underbody light kits – These are the lights that everyone has seen under the Honda Civics in the movie “The Fast and The Furious” and on many cars in this area. These lights in and of themselves are not against the law and if properly mounted and operated are not against the law either. The lights have to be mounted under the vehicle to where the bulbs/light assemblies are not seen to where the light only illuminates the ground directly under the vehicle. The lights if turned on must be on one color (not changing colors). If the light kit is used when the vehicle is traveling on a public roadway, the previous mentioned items must be complied with. If the light is shining to the front, back, left or right sides, and/or the lights are strobing, flashing, or changing colors, the light kit violates the law and the driver can receive a citation.
Aftermarket exhausts/mufflers – Yes, you have heard the loud Harley style noise and the Lawnmower noise coming from some cars in the area. These are due to the owner/operator having either a bad exhaust, drilled holes in their exhaust pipe or muffler, or they have substituted their stock mufflers/exhausts for aftermarket ones. These items violate both city ordinance of loud noise and state law pertaining to mufflers since the job of a muffler is to “MUFFLE” the noise.
Stereo's, TV's, and Speaker - Yes, there are many wonderful and powerful car stereos and thumping woofer speakers out there. They have the stereos with the flip out screens, lighted amplifiers, and woofer speakers as big as your back seat. However, legally, you cannot turn your radio up so loud that it can be heard outside your vehicle causing a disturbance of the Peace. The offense of Loud Noise (Vehicle) carries a hefty fine of up to $2,000. Some places actually will start to confiscate your stereo and/or car for multiple infractions. The TV's are great too; however, they cannot be in view of the driver when the vehicle is operated on a roadway as that is an offense as well. If the TV is displaying pornography as you are driving down the roadway (yes, this has happened), that is also a violation of the law.
Really, all these items come under two words: Common Sense. If you think it is breaking the law, it probably is. If you are not sure, contact a local Law Enforcement and ask for assistance or advice.