Do New Struts Need to Break in?

struts and spring(often called coils) do not need a breakin period.. the bottoming out part comes from the fact that the Koni (sport) struts have a longer piston shaft than the KYB's (for a lower overall ride height)..

Do new struts have to be broken in?

Things may feel a little bouncy at first

First, a new set of shocks and struts needs to be broken in just like anything else. ... This means the amount of “give” in the shocks will gradually increase over time. Second, a brand-new passive suspension will feel especially rigid in comparison to a worn-out active suspension.

Will new struts make my car sit higher?

Shocks/struts don't do anything to change ride height unless they have adjustable perches. All they do is dampen the amount of jounce and rebound caused by the springs when going over bumps.