There is a good chance that the rollers need to be replaced.
Unplug the dryer and pop the top up. Then remove the front of the dryer.
Remove the belt from the idler pulley at the bottom of the dryer.
Next remove the drum and you will see the two rollers (part # 349241T
) that the dryer drum sits on.
I think you will find that it's the belt idler (part # 691366
) or one of the two rollers that are making the noise. Give them a spin by hand and you should be able to tell what one is making the noise.
When you find the one giving you the problem you can try to oil it but I have found out over the years that it's best to replace the part and move on.