Is there a way to limit who can view parts of forums to certain rosters? Basically I am part of a 3 guild alliance. We share 1 common website. We would like it so all 3 guilds can have a private section of the fourms just for each guild.. That way you have to be part of that guilds roster to view/create or reply to posts.

This isn't currently possible.

You can restrict the sub forums by rank, but the higher ranks will be able to see the lower ranked forums.

Best solution is for each guild to get their own site if you want to do this.