The front of the drum rides on glides that are riveted into the front panel. It sounds like those glides are going bad. When the wear out, you get metal on metal rubbing. If this is the case thought, I would replace the glides, belt, drum rollers, and idler pulley. Since you already have it open to replace the glides, it would be best to replace all of them. Do you want me to look up the parts and tell you how to access everything? Or would you be calling a tech out to your home to repair this?
To access the inside of the dryer. Remove the lower panel by removing the two screws that hold it on. Then pull the panel away. Then remove the two screws on the bottom of the front door panel that hold that panel to the frame of th edryer. Pull the front door panel away from the unit and then pull it off of the dryer, be careful there are wires to the door switch on this panel. Disconnect the wires. Then remove the screws around the panel that hold the drum in place and remove that panel. Here is where you will see the glides I was talking about. These actually aren't riveted in, you can just replace them with the glide and felt parts. Then to replace the other parts, undo the belt from the pulley by reaching in under the drum on the left side behind the fan. Release tension on the belt by pushing the idler down and remove the belt from the idler. Then you can remove the whole drum. From there you will see the rollers in the back and the pulley by the motor. Just un-clip the clip that holds those parts on and replace. Then replace the belt and reverse the entire process to put it back together.
Glide, part number 37001298, order two, cost is $5.16 a piece
Felt, part number 500121, order two, cost is $3.29 a piece
Roller, 37001042, order two, cost is $6.69 a piece
Belt, 40111201, order one, cost is $25.60
Idler, Y54414, order one, cost is $5.53
You can order the parts at sears parts direct.com.
Here is the link to a breakdown