From the description of your problem the most likely cause of this problem are the drum rollers.
There are two drum support rollers and they come packaged together in a kit number 349241T which is available from the following link:
You didn't ask but replacing the drum rollers can be a do-it-yourself project.
To access the drum rollers first pull the lint screen out and remove the two screws located there. Then use a putty knife to locate and release the two clips located about 2-4 inches in from the front corner and raise the top which is hinged in the rear.
Remember to unplug the dryer first.
With the top up there are two bolts holding the top of the front panel to the cabinet. With these bolts removed you can pull out and up on the front panel to release it.
With the front panel off you can remove the drum to access the drum support rollers. First take a good look at the belt and how it is routed around the idler pulley.