Does replacing the engine reset mileage

Replacing a car’s engine does not reset the vehicle's mileage. The mileage recorded on the odometer reflects the total distance the vehicle has traveled, not just the engine. However, there are some key points to consider:

Odometer and Engine Are Independent

The odometer tracks the overall use of the entire vehicle, including components like the transmission, suspension, and chassis. Since these parts still experience wear and tear, legally and mechanically, the mileage remains unchanged.

Recording Mileage After an Engine Swap

Even though the engine is replaced, the odometer will continue counting from its previous reading. Some vehicle service records may note the engine change, but the original mileage is still displayed on the dashboard.

Engine Longevity vs. Vehicle Age

A new or rebuilt engine can extend a vehicle’s lifespan, but other parts (such as the transmission, suspension, and electrical components) still reflect the original mileage. This is why a vehicle with a new engine does not necessarily have the same value as a brand-new car.

Legal Considerations

In most regions, tampering with an odometer or rolling back mileage is illegal. If an odometer is changed or reset after an engine replacement, it could lead to legal consequences, especially when selling the car.

Indicating a New Engine in Vehicle History

For buyers and sellers, it’s good practice to document the engine replacement. Service records, receipts, and even updating vehicle history reports (like Carfax or Autocheck) can help maintain transparency.

Exceptions

Some digital odometers are connected to the engine control module (ECU), which may reset after replacing both the ECU and engine together. However, in most cases, modern vehicles store mileage in multiple places, preventing a full reset.

Conclusion

Replacing an engine does not reset the vehicle’s mileage, as the odometer tracks total vehicle usage, not just the engine's wear. If you're buying or selling a car with a new engine, keeping proper records helps ensure transparency and trust.