When you need replace your old car shock absorber/Air suspension shock/air spring?

When you need  replace your old air suspension/ car shock absorber/ Air suspension shock/ air spring?

 1.Abnormal noise disturbing people: In order to control the direction, the shock absorber is annoying, and the abnormal noise disturbs people.
2.Bumps in the body: bumps on uneven roads, unable to maintain stable driving
3. Poor quality: affect the normal use of other parts
4. The bottom of the car body sinks: the bottom will appear when the load and road conditions are bad
5. Tire wear: frequent and irregular tire wear
6.Air suspension shock/car shock absorber/ air suspension strut Leak oil.