Open the door and look for two phillips head screws going into the top of the door frame. Removing these will allow you to "pop" up the top and slide it off. There are then two hex head screws holding the front panel. Remove these and you now have access to the interior of the machine.

Reach is to release tension pulley on the belt, and then you can remove the drum to determine your problem. Look for a problem with the rear bearing or the rollers.

Click on your model number to get a set of exploded views for your machine and to order the parts.

Good luck, and post how it turns out.