How to Make Modified Cars Legal for Road Use?

[Louise]

Modified cars can be legally driven on the road if they comply with regulations. Detailed explanation on making modified cars legal for road use: Aftermarket parts should match the original wheel size (including J-value and ET-value). If new tires are installed, the diameter difference between the old and new tires should ideally be kept within 3%. Policies allow the installation of roof racks with a height not exceeding 30 cm. Side steps are generally categorized into fixed and electric retractable types, both of which can be modified. Parts that cannot be modified include: Powertrain, exhaust system, and spoiler modifications. Any modifications require filing with the authorities.

[LeFinn]

If you want your modified car to be legally roadworthy, it's actually quite straightforward—the key is to follow the regulations. First, ensure the modifications don’t compromise the vehicle’s basic safety and performance, such as brakes and lights, which must meet national standards. Then, promptly visit the vehicle management office to register the changes, bringing along your license, ID, modification list, and other required documents—just fill out an application form. A friend of mine once modified his exhaust system but got fined for driving without declaring it, so never skip this step. For major modifications like suspension or engine work, it’s best to have a professional repair shop inspect them, as they know how to test emissions and safety compliance. Remember, annual inspections are stricter, so drive responsibly (e.g., avoid speeding) to stay off the traffic police’s radar. In short, follow the proper procedures step by step, and legal roadworthiness won’t be an issue—plus, you’ll avoid future hassles.

[VonPreston]

To legally drive a modified car on the road, I believe the most important thing is to be familiar with traffic regulations. The law stipulates that any vehicle modification must be registered. You need to personally visit the traffic management department, submit a modification description and vehicle photos, and wait for approval. I've handled a similar situation before—after widening the wheel arches for appearance modifications, it took some time to get the certification done. Modifications must not involve critical components such as the chassis structure or affect environmental standards, otherwise they won't pass inspection. Another issue is insurance—after modifications, you must promptly notify your insurance company to update the policy terms, otherwise claims might be denied in case of an accident. Also, don’t neglect regular maintenance; check the wiring periodically to avoid circuit overload. Although these steps may seem tedious, they ensure safety and legality, making driving much more reassuring.

[DelLaila]

I've modified my car before, adding body kits and some decorative parts. To make it road-legal, I went directly to the local DMV with all the necessary documents to register the changes. The whole process wasn't too complicated—just filling out forms and waiting in line for half a day—but after modifications, you must ensure it doesn't affect basic functions like braking and steering. Once on the road, just avoid driving too fast and follow traffic rules, and you'll be fine. I recommend checking regulations before modifying, such as ensuring the exhaust isn't too loud.