Can the same steel number be stamped when replacing the engine?

[JulietFitz]

It is not allowed to stamp the same steel number when replacing the engine. If the engine number is different after a new engine replacement, the vehicle registration must be updated with the new engine number. Engine stamping number: Positions 1-3 (WMI): World Manufacturer Identifier, indicating the manufacturer of the vehicle; Positions 4-8 (VDS): Vehicle Descriptor Section; Position 9: Check digit, used to prevent input errors through a specific algorithm; Position 10: Model year, which is the year designated by the manufacturer for the model, not necessarily the actual production year, but generally the difference does not exceed one year; Position 11: Assembly plant; Positions 12-17: Serial number. Typically, vehicle recalls target a specific range of serial numbers, i.e., a particular batch of vehicles. How to check the car engine model: The simplest method is to look at the vehicle's nameplate, which is usually located inside the door frame of the driver's side door. Additionally, the engine model can be found on documents such as the vehicle registration certificate, owner's manual, factory certificate, and compulsory insurance policy. The difference between the engine model and the engine number is that the engine model refers to the naming of the engine, while the engine number is a unique identifier, with each vehicle having a different one.

[SanSophie]

I've got plenty of experience with engine replacements – you absolutely must not reuse the original engine number. The new engine comes with its own unique factory-engraved serial number, which serves as its ID. If you privately engrave it to match the old engine's number, the DMV will spot the discrepancy immediately when they cross-check their records during inspection. Last year I helped a friend deal with this exact situation – the owner tried cutting corners by duplicating the old number, only to have the registration modification rejected outright. They ended up having to grind off the number and re-engrave it properly, wasting over 2,000 RMB in repair fees. Always use the new engine's original serial number and bring the certificate of conformity to the DMV for the modification procedure. It's more paperwork, but it's the only legal way.

[Thompson]

Having worked in auto repair for twenty years, the most dreaded request from car owners is this. The engine serial number is a state-registered anti-counterfeiting identifier, just like a human fingerprint that cannot be replicated. New engines come with laser-engraved alphanumeric combinations upon arrival. If someone manually stamps the old number, the depth and angle of the engraving marks left by the tool are completely different from the factory originals—traffic police can spot this in three seconds with professional equipment. Even worse, such actions trigger legal recognition of engine number tampering, resulting not only in mandatory vehicle scrapping but also the owner facing a 12-point deduction and a 5,000-yuan fine. It’s far better to follow the proper procedures for peace of mind.

[LandonRose]

Last year, I had my engine replaced. The repair shop directly told me not to worry about the engine number issue. The new engine came with a complete serial number when it was taken out of the warehouse, and even the cylinder block position was identical to the original factory specifications. The mechanic explained while helping me with the modification procedures that each vehicle corresponds to a unique engine number in the DMV system, and duplicate numbers could cause information confusion and make filing impossible. Moreover, during annual inspections, machines scan and verify the number, and the old number would be flagged as an illegal modification. The entire modification process took only half a day, and now there are no issues driving it, not even affecting my insurance renewal.

[DelMatteo]

From a vehicle management perspective, the engine serial number is a permanently bound unique identifier. When replacing an engine, it is mandatory to use the original factory-stamped serial number that comes with the new engine to complete the change registration, as clearly stipulated in Article 16 of the "Motor Vehicle Registration Regulations". Reverting to the old number constitutes tampering, akin to forging an ID card, and will inevitably be detected during annual vehicle inspections or ownership transfers. The most severe case we've handled involved criminal charges against a vehicle owner for forging serial numbers, which facilitated illegal vehicle modifications and license plate fraud. Therefore, never take chances—ensure all documentation for the new engine is complete and in order.

[TessaRose]

A friend just replaced his engine and asked me about the serial number. I clearly stated that a new number must be used. Firstly, from a legal perspective, privately engraving the original number constitutes tampering with the engine serial number, which directly violates Article 16 of the Road Traffic Safety Law, and the vehicle will be impounded if discovered. Secondly, in practical terms, the stamping position and dimensions of a new engine are standardized, and manual engraving can easily result in uneven depth, raising suspicions. Lastly, it affects the vehicle's value—when selling the car in the future, if buyers check the maintenance records and find the number has been altered, they will either demand a price reduction of 50,000 or outright refuse the purchase. Overall, it’s far better to follow the proper procedures.