I have a continental trailer with brakes. I'm having a problem where every time I head out...one of the brakes is locked. After I move a couple of feet..it unlocks and is good for the rest of the day. I"m trying to take the drum off to see what is going on. My problem is..the drum won't come off. It looks like the drum and the housing(hub) is one piece? I've removed the outter bearings and I'm trying to get the thing out ,but it appears to be stuck. Any ideas??