Coil spring is the most widely used spring in modern cars. It has strong shock absorption ability and good ride comfort; The defect is that the length is relatively large, occupying more space, and the contact surface of the installation position is also relatively large, which makes the layout of the suspension system difficult to achieve very compact. Because the coil spring itself can not withstand the lateral force, it is necessary to select the complex combination mechanism such as four-bar coil spring in the independent suspension.
From the consideration of riding comfort, we expect that the spring can reflect a little softer for the ground impact with high frequency and small amplitude, and when the impact force is large, it can reflect relatively large rigidity and reduce the impact stroke. Therefore, the spring should have two or more stiffness at the same time. Springs with different wire diameters or different pitch can be selected, and their stiffness increases with the increase of load.

Leaf springs are mostly used in van and truck, and are composed of several slender spring sheets with different lengths. Compared with the coil spring, it has the advantages of simple structure and low cost. It can be compactly assembled at the bottom of the vehicle body. When working, friction is formed between the plates, so it has attenuation effect. However, if serious dry friction is formed, the ability to absorb impact will be affected. Modern cars that attach importance to ride comfort are rarely used.