spaceman

What is this washer? Its bolted into the end of the axle. I am having alot of trouble reinstalling the Hub cover over this nut and over the axle. Any suggestions on how to reinstall it? When I removed the hub cover (via using bolts through the threaded holes to pull it out) the washer was free spinning and it didnt seem like the bolt was torqued tight at all.

Do I even need this washer for ADD? Anybody know what it does? Thanks (I tried searching but couldnt really find anything)

Whats the best way to go about pressing it back on?

edit: im an idiot, figured it out, plz delete thread