After a few months and a can of lithium grease I finally found the culprit. I feel like an idiot. It was the bolt that holds the brake line to the leaf assembly rubbing on the leafs. The AAL creeped sideways enough to start rubbing the bolt threads. Actually looks like it rub a couple threads off. Hopefully this helps someone else out. I knocked the AAL back into place. Now I need to figure out a contraption to keep it line up.