Your washing machine is supposed to clean your clothes, but what if it's getting them dirty in the first place?

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Day in and day out, we mindlessly depend on our washing machines to handle the tasks they were designed to do. Usually, this workhorse appliance tackles the job of cleaning our laundry, from filthy jeans with ground-in grass and mud stains to wet towels and more delicate garments, in steadily reliable style. Dirty laundry goes in, clean clothes come out -- almost like magic!

But magic gets dark sometimes. What if your washing machine suddenly starts leaving stains on your clothing that weren't there before? If it's an oily or greasy stain, the problem could be an issue with your particular model. Check the Web site for your washing machine's brand to see if a history of problems exists, then follow the instructions to resolve the situation or contact the manufacturer for more information.

No model defect to blame? It could be that the washing machine drum has collected greasy residue from previous loads. Try cleaning the drum by running an empty cycle with a cupful of white vinegar or bleach instead of detergent, or look for products specially designed for this purpose. Then, wipe out the drum and around the door seal with a clean, dry cloth, and use a cotton swab to clean around the drainage holes.

If the stains are reddish, it might be rust that has formed due to chipped enamel on the drum or in the dispenser. Many washer manufacturers offer drum replacement options. If you like fixing things yourself, try sanding and then painting the chipped spots with a rust-resistant paint.

Another source of mysterious stains could be fabric softener clinging to greasy spots. To solve this problem, reduce the amount of fabric softener that you use or try not to pack too many clothes in each load. The fabric softener needs to disburse evenly over clothing to work properly, so experiment to find the correct load size and amount of additive that result in the desired amount of softness without any spots.

If you're tried all of these solutions, and your laundry is still coming out of the wash with inexplicable spots, your dryer could be the culprit. In that case, try the same model troubleshooting tips you performed for your washer, clean out the inside drum and door seal, then call an appliance repairman.