How Shock Absorbers Function

The top of a double acting shock absorber is mounted to the frame and the bottom is mounted to a fixture on the suspension or axle in the vicinity of each wheel. In simple terms, a piston inside the interior cylinder of the shock moves up and down through oil that is sealed within the cylinder. Small holes in the piston slow the movement of the piston and provide the dampening effect of the oil shock damper. The piston is mounted on a shaft that runs out the top of the shock cylinder; a seal around the shaft keeps oil from leaking out of the cylinder. The shaft is a part of the top of the shock that attaches to the frame, while the cylinder is a part of the bottom of the shock that attaches to the axle or suspension.