Several situations that require four-wheel alignment:

1. The driving performance of the vehicle is affected (the most direct feeling of the driver is the deviation, and the steering does not automatically return to the wheel, which is also considered one).
2. The chassis and suspension are damaged due to accidents.
3. Abnormal tire wear (but also consider whether the abnormal wear is caused by abnormal tire pressure. Generally, too high tire pressure will aggravate the wear of the center of the tread, while too low tire pressure will aggravate the wear of the tread. Wear on both sides, if there is eccentric wear on one side, there may be a deviation in the camber angle.)
4. The axle and suspension parts have been removed.