After a certain mileage, as long as the car passes through a small pit or uneven road surface, there will be unstable driving phenomena such as steering wheel jitter and body swaying from side to side, which will lead to driving difficulties for drivers and seriously affect driving safety. Professional maintenance personnel believe that the reasons are as follows:

1. Toe-in: The steering tie rod and the steering tie rod are deformed due to collision, and the toe-in increases or decreases due to loose ball head wear or irregular tire wear.

2. Wheel dynamic balance: After driving for a certain mileage, the original wheel dynamic balance lead block is lost and the wheel hub is deformed. When driving at high speed, the front of the car swings and the steering wheel shakes.

3. The ball head of the transverse push rod is loose or the bracket is loose, which leads to the instability of the car when driving.

4. The wheel hub bearing is loose, and the left and right steering knuckles are seriously worn, which leads to the inaccurate positioning of the front wheel of the automobile.

5. When the car is driving, oil leaks due to the damage of steering shock absorber or the deformation of front suspension spring, which also affects the stability of the car.