Guide to cleaning your front loading washing machine to avoid the mildewy smell - already read this whole article and it goes for top loaders too! I do this w/my front-loader, have from the beginning and I use white vinegar for virtually EVERYTHING, so I have never had this problem. Great advice for these washers and I use the homemade powdered detergent recipe at the end and it works great!
Over time, towels build up detergent and fabric softener, leaving them unable to absorb as much water and smelling funky. Recharge them by washing them once with hot water and one cup vinegar, then a second time with hot water and half cup baking soda. This strips the residue and leaves them fresh and able to absorb more water again. Works like a charm!