We had heard that front loaders were infamous for mold, so we use Affresh tablets every month or so to clean our washing machine. The other day I was doing the laundry and pulled out the tray to add my laundry detergent. I bent over to pick something up and noticed mildew around the bottom edge of the tray. Zach undid some of the screws and pulled the tray out.
It was horrible.
The part that we couldn't see from the outside was COVERED in black mildew. Looking in further we could see more of the gross black mess. Zach ended up having to take apart the rest of the washing machine so we could clean all the mildew.
I felt pretty dumb when I dug the manual out of the filing cabinet and found the maintenance guide simply outlined on two pages. This probably would have prevented all the dismantling, scrubbing, soaking, and bleaching.