This is a common question that we receive as the terms shock and strut are often used interchangeably. A shock and a strut do the same basic job on a vehicle, damping the movement of the spring and stopping oscillation and bounce. Even though they do the same thing, shocks and struts are completely different parts. A shock cannot be used to replace a strut and a strut cannot be used to replace a shock. A vehicle will have either a shock or a strut at each wheel, never both. Every vehicle was designed with either shocks or struts and your vehicle's suspension cannot be changed to use the other.
The major difference between shocks and struts is that a strut is a structural part of the vehicles suspension system where a shock is not. A strut is also crucial part of the vehicles steering system and greatly affects alignment angles. Camber and caster angles are usually adjusted right on the strut itself. A strut is also a pivot point for the vehicles steering system and contains a coil spring. Because of this an alignment is always needed when replacing a strut. This is also the reason that struts are typically more expensive than shocks.
People often call in saying they have been told they need shocks and struts. This is usually a friendly neighbor with a less than perfect knowledge of suspensions trying to be helpful. Because the terms are used interchangeably, customers often get confused as to which they need. To add to the confusion, some vehicles have struts on the front axle and shocks on the rear. If you search for your vehicle on Shockwarehouse, you will only see the correct units for your vehicle - struts if you need struts and shocks if you need shocks.
A Strut. Note the spring perch that holds the vehicle's coil spring, making the strut an integral part of the vehicle's suspension.