Struts don't need to be replaced unless your vehicle is bouncing like it's on a pogo stick or bottoms out in potholes and over railroad tracks — or unless a mechanic finds that they're leaking fluid or have been damaged. In some climates, they can also rust.

What happens if you don't replace struts?

Safety: Worn struts result in longer stopping times and/or distances as the vehicle weight can shift (sometimes unexpectedly) during braking. ... Wear on other parts: Driving with bad struts accelerates the wear on tires, as well as other components of the suspension system, such as the springs.

How do I know if my struts need to be replaced?