You are talking about the fork that supports the strut assembly correct?



The bolt is not threaded in, but the strut is exerting downward force against the bolt. Couple ways to go about it: loosen the clamp bolt that secures the fork to the strut tube so it can slide up, or place a jack and lift the fork slightly without applying pressure to the lateral arm.

Either way you need to relieve the pressure on that bolt for it to slide out.