Shocks and Struts - What's the Difference?

Both shocks and struts are designed to damp the harmonic oscillation of the car's springs after hitting a bump, or taking a curve. The most common shock absorbers have a “twin tube” design that makes up a hydraulic pump that sits between the car frame and the wheels. They work in a compression cycle and an extension cycle – the compression cycle compresses the hydraulic fluid downward (as the piston moves down) while the extension cycle occurs when the piston moves up, compressing the hydraulic fluid in the opposite direction. Most modern shock absorbers are speed sensitive so the faster the car moves, the more resistance the shock absorber gives.