Product review (5 stars): If your dryer is louder than a whisper then replace the rollers!!
Mom's dryer got to a point that it was annoyingly loud, I had replaced some parts on my own washer and dryer previously in the year and was fairly certain these would fix the issue. After getting the dryer apart and looking at the old rollers I was doubting they were the issue because they looked brand new still. Nevertheless I replaced all 4 rollers using the old axles and plastic triangles and wallah! Perfectly silent dryer making us marvel about how quiet the dryer was new and just how loud it had gotten! If you haven't pulled apart a washer or dryer before then get the service manual because they can be tricky to get apart.