What is the Definition of Illegal Vehicle Modification?

[StFrancisco]

Illegal vehicle modification refers to altering a vehicle's appearance, power system, transmission system, or braking system beyond the limits permitted by national laws and manufacturer approvals, exceeding the original design load capacity and functionality. This includes replacing critical components. Article 16, Item 1 of the Road Traffic Safety Law of the People's Republic of China stipulates that no entity or individual may assemble motor vehicles or arbitrarily modify the registered structure, construction, or features of a motor vehicle. Without approval from the public security traffic management department, any unauthorized modifications to the vehicle's chassis, engine, suspension, transmission system, steering system, tires and rims, lights, body color painting, or exterior structure, as well as any technical data that does not match the data announced by the State Council's motor vehicle product authority, are considered illegal modifications. According to Article 10 of the Regulations on the Registration of Motor Vehicles (Order No. 124 of the Ministry of Public Security), if a registered motor vehicle undergoes any of the following changes, the owner must apply for modification registration at the local vehicle management office: Changing the body color; replacing the engine; replacing the body or frame; replacing the entire vehicle due to quality issues; changing the use nature (e.g., converting a commercial vehicle to non-commercial use or vice versa); or relocating the owner's residence into or out of the jurisdiction of the vehicle management office.

[LeLondon]

Regarding illegal modifications, I think this is quite common, but many people aren't clear about its exact definition. Simply put, illegal modification refers to unauthorized changes made to a vehicle's structure, construction, or main characteristics without approval from the vehicle management department. For example, if you modify the rear exhaust pipe to look like a dual exhaust or add an exaggerated large spoiler without filing the changes, it counts as illegal. I've even seen people privately lower their chassis height, resulting in deformed suspension systems - these are all violations. Of course, the most serious case is engine modification, such as reprogramming the ECU to boost power, which might lead to immediate vehicle impoundment by traffic police. If you really want to modify your car, remember to apply for change registration at the vehicle management office first. Otherwise, if caught, you could face fines, and in severe cases, the vehicle might even be forcibly restored to its original condition.

[Ria]

Having been in this industry for over a decade, I've encountered many car owners who got into trouble due to illegal modifications, often simply because they didn't understand the regulations. Illegal modifications, to put it bluntly, are unauthorized alterations made to vehicles that violate the 'Motor Vehicle Registration Regulations.' The state strictly regulates over a dozen such modifications. For instance, changing brake discs and calipers, installing larger-sized rims, or altering the color of brake lights all count. Then there are off-road enthusiasts who raise their chassis without reinforcing the drive shaft, making driving extremely hazardous. I always remind car owners to check if modifications like installing intake air filters or altering exhaust valves comply with GB standards before proceeding, rather than blindly pursuing a cool look. After all, during traffic police inspections, the focus is on the engine compartment and braking system—any unregistered modifications are easily spotted.

[DelEmmanuel]

Back when I first bought my car, I was eager to customize it for a cooler look, but almost got caught up in illegal modifications. Later, I learned that illegal modifications refer to unauthorized changes that can result in fines if driven on the road. The most typical examples include widening tire sizes beyond the factory-designed percentage, which is considered non-compliant, or installing xenon headlights without lenses, which can blind oncoming drivers at night. Nowadays, policies have relaxed a bit—for instance, changing the car's color covering less than 30% of the body doesn't require registration, but adding a roof rack exceeding 5 cm in height must be reported. A friend of mine was fined 500 yuan for replacing the steering wheel, only to realize that factory airbags must not be removed. Remember the core standard: modifications involving safety, braking performance, or emissions are 90% likely to require approval.

[StLaura]

The concept of illegal modification is clearly defined in the automotive repair industry. According to our maintenance manual standards, any replacement that deviates from the original factory specifications is considered a modification, and its legality depends on whether it has been registered. For example, dismantling the engine to replace piston rings is illegal, but swapping to wheels of the same size is not. Audio system modifications are particularly prone to violations—installing a subwoofer in the rear seat can overload the wiring, posing a fire hazard. For chassis modifications, air suspension systems must retain sufficient buffer travel to prevent rollover risks. Lighting system alterations are another major issue, with aftermarket laser headlights lacking proper cooling devices being outright violations. We advise vehicle owners to photograph any parts before removal and obtain compliance certificates from authorized modification shops, ensuring evidence is available during inspections.