Maybe you never considered that something that exists to clean would need to be cleaned regularly. Giving your machine a periodic clean-out using bleach and vinegar (in separate cycles!) helps to eliminate residue left behind by soaps, and improves the ability for your machine to clean your clothing thoroughly. A must-do if you’re sitting at home with a few hours to kill!

Getting your laundry back on track starts with just two items*:
• 1 quart of bleach (many tutorials went without the bleach step, if you’re concerned about using harsh agents in your laundry)
• 1 quart of white vinegar

* Some of you might be thinking: But wait, isn’t it dangerous to mix bleach and vinegar? The answer is yes, but we will not be mixing the two here. Read on …

Alternate option: Vinegar with baking soda will do a very good job of cleaning the inside of your washer and leave it smelling fresh, but I would suggest a couple of cups vinegar, rather than a whole quart.

Fill the empty washer with hot water, as if you’re doing a large load of laundry. Add the quart of bleach, and let the full machine run for one minute to mix up the bleach with the water. Open the top of the machine and let it sit, all bleach-y and full, for an hour. At the end of the hour, shut the cover and let the machine run a complete cycle. (The water will drain out all the bleach, so it won’t have a chance to mix with the vinegar.)

When it’s done, start again. This time, when you fill the washer with hot water, add the quart of white vinegar to the water and down the bleach channel and let the machine run for a minute to agitate the water and vinegar. After that minute, open the top of the machine and again, let the hot water sit in the basin for an hour before you let the cycle complete.

- See more at: http://blog.diynetwork.com/maderemade/2013/04/30/get-your-laundry-back-on-track/#sthash.hixqu3S6.dpuf