I stopped by Iron City Bikes after work today to see if they could change out the freewheel. It turns out that my rear axle is bent. Fairly badly, too. Well, that what I get for using a freewheel and stressing it out with a Bob Yak trailer. So, I'll be getting a new wheel (knew that was coming) that designed differently so that there isn't the stress on the axle. They had to order the wheel for later this week and it'll end up costing me $100 or so.