Trouble with strut bolt

[jakeru]

Is the problem that the whole thing spins when trying to remove the nut? [If so, you'll want to counter-hold the wrench flats, or otherwise, maybe impact wrench or hammer can "jar" the nut loose.]

Or is the problem that after the nut is completely removed, you're having trouble withdrawing the bolt from the steering knuckle?
[if so, the main thing is to alleviate tension on the bolt. You can make sure the swaybar is not stressed, and relieve the weight of the strut by jacking up a modest amount on the ball joint. Modest amount means the strut's spring is just barely starting to compress.

You can also hammer lightly on the bolt end. Recommend being careful here and just going light, to avoid mushrooming the threads. Using a steel rod or something can help save the bolt end. You can also partway-fasten the nut and hammer on the nut, to save the end of the bolt. But to reiterate, relieve the pressure on the bolt, and gently tap it free. It will come out!

I also 100% second the notion to clean and anti-seize all of these suspension fasteners that you encounter, before buttoning things back up.]