I'm stumped as to what is causing a noise in a Maytag dryer, SDE4000AYW. This is my neighbor's machine, and of course it wouldn't make the noise when I was present.
However, based on her description I replaced the following parts:

  • Drum support rollers
  • Belt
  • Idler pulley wheel and bearing
  • Drum glides (supports front of drum)

It turns out that an important aspect of the problem (unknown to me previously) is that the noise only occurs when the dryer is hot. I had been testing with a cool dryer. When I had the heat going I did hear the noise and I noticed that it was not periodic, but did come and go. When the noise was occurring the belt vibrated rapidly on the side not riding on the idler pulley. The motor did not seem to be vibrating, however. Then things would quiet down and the belt would ride smoothly. The noise is not a squeak or rattle, but more of a groan.

After some more research, I pulled the motor and blower assembly and inspected the blower for any damage. It was fine. I spun the motor by hand and it was very free, so I blew all the lint out and put it back in the dryer. The noise still persisted. Thus, I am at a loss as to the cause. My only suspicion is motor bearing wear, but I sure don't want to buy a new motor on speculation.

Any advice would be highly appreciated!