My Maytag Performa with bottom freezer is making an intermittent buzzing/vibration sound that reminds me of bearings on a computer fan when they go out.
It will buzz for only a few seconds and then may go a day or so without doing it again. Sometimes it will make this sound every few minutes for several hours and then quit.
The floor is flat Pergo. Sound is coming from rear down low. I pulled it out and cleaned the fan and blades as well as the condenser coils. Didn't seem to have any effect. As near as I can tell, all of the brackets are tight and I can't feel any loose fittings anywhere. Fan motor seems to be OK when I examined it visually and when I tried to check for excessive end play.
It would be nice to anticipate the problem and have repair parts on hand whenever the defective part goes out.
I have read the other two Maytag intermittent noise posts on this forum.

Thanks very much for the links to valuable information.

I believe I will pull it away from the wall and wait to see if it will make the noise at a time when I can get behind it and pinpoint the source.

Probably wouldn't hurt to have a spare fan.

Thanks again for helping me.