In order to reduce the vibration of the frame and body quickly, improve the ride comfort and comfort of the car, the vehicle suspension system is usually equipped with shock absorbers. At present, a two-way action cylinder type shock absorber is widely used in the automobile. Shock absorbers are vulnerable parts in the process of automobile use. The work and quality of the shock absorbers will directly affect the stability of the vehicle and the life of other parts. Therefore, we should make the shock absorber always in good working condition, and the following methods can be used to test the good work of the shock absorber. It makes the car stop after 10km on the road with poor road conditions, and touch the shock absorber shell with hand, if it is not hot enough, it shows that there is no resistance inside the shock absorber and the shock absorber does not work. At this time, the proper lubricating oil can be added to the test, and if the shell is hot, the oil is deficient inside the shock absorber, and the oil should be added. Otherwise, the shock absorber is invalid, and the bumper is pressed and then loosened. If the car has 2 ~3 jumps, the shock absorber works well; when the car is slow driving and emergency braking. If the vibration of the car is more violent, it indicates that the shock absorber has problems; remove the shock absorber and put it upright and clamp the ring on the table forceps to press the shock rod several times. At this time there should be stable resistance, the drag of the upward pull should be greater than the downward pressure resistance, such as the instability of the resistance or the no resistance, it may be the internal of the shock absorber. Repair or replacement parts should be repaired if oil or valve parts are damaged. After determining the problem or failure of the shock absorber, check whether the shock absorber is leaking oil or has traces of old oil leakage. The oil seal washer and the sealing washer are broken and damaged, and the nut of the oil cylinder cover is loose. It may be the damage of oil seal and sealing washer. New seals should be replaced. If the oil leakage is still not eliminated, the shock absorber should be pulled out. If there is a hairpin or light weight, further check whether the gap between the piston and cylinder is too large, the piston rod of the shock absorber is bent, the piston rod surface and cylinder have scratches or scratches. If there is no oil leakage in the shock absorber, check whether there is any damage, welding, rupture or shedding of the damper connection pin, connecting rod, connecting hole, rubber, bushing and so on. If the above inspection is normal, the shock absorber should be further decomposed to check whether the clearance gap between the piston and the cylinder is too large, the cylinder is pulled, the valve is sealed well, the valve and the valve seat are closely fitted, and whether the extension spring of the shock absorber is soft or broken, and repairs or replacement is taken according to the condition. . In addition, the shock absorber will have a sound failure in actual use, which is mainly due to the impact of the shock absorber with the steel plate spring, the frame or the axle, the damage or shedding of the rubber cushion, the deformation of the shock absorber tube and the insufficiency of the oil, and the reason should be found out. When the shock absorber is checked and repaired, the performance test should be carried out on a special test bed. When the resistance frequency is 100 + 1mm, the resistance of the extension stroke and the compression stroke should be in accordance with the regulations, indicating that the shock absorber is basically normal.