Motor turn but not drum

The other day when i put a load in the dryer and turned it on the motor started but the drum would not spin, so i took every thing out and then tried it again and helped it get going and it was fine. But it has been squeaking randomly when its running for a while now and i already looked at the parts break down and im thinking that the two rollers on the back of the drum and the front drum bearing are probably worn out and was gona put a new belt on too. Let me know if i sound right and if there was anything else that could be wrong.