Here's a really dumb question: do 4C struts expand like regular struts, or should they be able to be moved easily by the hand when removed from the vehicle? I just removed one of the 4C struts on my 2004 S80 to replace the spring seat and found that I could easily move the 'plunger' part (sorry, don't know what it's officially called) by hand. My thought is that maybe 4C struts might behave slightly differently than regular struts since they're electronically controlled, but I could be completely off-base.

 

I guess it depends what setting you have it on, sport or comfort when you took it off, but otherwise the same pretty much.