Kenmore dryer model 110.86984100 has a loud, intermittent squeek/squeel when it is running. Heats and spins fine, just starts squeeking occasionally. The squeeking can get quite loud (sounds like a squirrel shattering) but then will calm down and go away for a few minutes.

I've replaced the frozen idler pulley -- it spins freely now. I cleaned the four drum rollers - they appear to be in good shape and are all spinning fine while the drum is turning. The belt shows some cracks but is sound. Also cleaned the entire inside of the dryer, so there isn't much dust/lint floating around.

Still squeeking. Any thoughts as to what might be the problem?