Shocks are individual suspension system components, whereas struts are key chassis and structural components. The primary function of the shock absorber and strut on a vehicle is to dampen the movement of the spring and prevent oscillation and bounce. While both help improves the smooth ride and handling of your car, they do it differently.
Table Summary
| SHOCK ABSORBERS | STRUTS |
| Designed to ensure the tires remain in contact with the road | They are designed to perform the function of shock absorbers and support and control the vehicle’s movement |
| A single device | A combination of multiple devices |
| Vehicle alignment is not needed when replacing shock absorbers | Vehicle alignment is necessary to replace struts |
| Cheaper than struts | Costs more |
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Definitions
The shock absorber’s principal function is to control spring and suspension movement. This is done by converting the kinetic energy of suspension movement into thermal energy, which is then dissipated through the hydraulic fluid.
A strut is a suspension component that combines the different parts of the vehicle’s suspension system into a single compact assembly. Struts are found on practically every front-wheel-drive vehicle. These include the coil spring, spring seats, strut bearing, steering knuckle, and shock absorbers.
Shock Absorber VS Strut
Functionally, shock absorbers work as oil pumps. A piston is attached to the piston’s end and works against hydraulic fluid in the pressure tube. The hydraulic fluid is forced through the orifices inside the piston as the suspension moves up and down. These orifices, however, allow only a tiny amount of liquid to pass through the piston. This slows the piston, which slows the spring and suspension movement. Struts, like shock absorbers, provide a damping effect and control spring and suspension movement like a shock absorber. However, Struts also have a secondary function. Struts, as opposed to shock absorbers, provide structural support for the vehicle suspension, support the coil spring, and keep the tire aligned. A complete strut includes additional parts such as inkling bumstops, mounts, and the coil spring.