[projectRDM]

First off, you're mixing words. The output shaft is the short piece that comes out of the diff, the axle is what you're talking about.
It should slide out with a little effort, however if you've been beating on it then you've already crowned the end of it and it's ruined. Get a puller and use that to push it through, then check and see how bad it's damaged by fitting the axle nut back on. Chances are you'll need a new axle. The metal threads are soft and don't take a beating very well.