Here is the link to this dryer GE DJXR473EV0WW
Could be a number of things
Try to locate where the squeal is coming from. Removing rear access panels and getting down and listening may help isolate it.
The dryer drum has a central bearing, should have an access plate on the back of the dryer. Try a little oil on the bearing. There is a good chance that even if this eliminates the noise you will be pulling the unit apart in the not too distant future to replace the bearing and maybe the shaft.
Other possibles are
Motor bearings
Belt tension roller
Front drum supports (plastic or felt) may be worn out and you are rubbing metal on metal | 
Loud Squeeling While Running 
