Horribly Squeaky Dryer

I looked up my problem online and everything I saw said to change the roller wheels that hold the barrel of the dryer. After doing that (twice, once on each side) I was still having a horrible squeaking sound so bad that we were waiting to do laundry until we were leaving for a while. Finally I determined that the problem was actually the idler wheel. All I had to do was remove the bolt holding the idler arm on (it's the arm that has a spring connected to it that moves to allow the belt on or off) and put the new arm with the new wheel on. The dryer is now whisper quiet and works perfectly.