Most "grease" stains that appear on freshly laundered clothes are caused by liquid fabric softener and/or dryer sheets. Fabric softeners work by leaving a lubricating coating on fabrics to make them feel softer. Excessive amounts of the coating will leave deposits on your laundry that look like grease or oil. If using a liquid softener, the spots will sometimes appear blue.
Try rubbing the spots with a wet bar of soap or liquid dish washing soap and then rewash. Don't use laundry detergent because it can actually set in the stains.
To avoid the spots, place the dryer sheet on the top of the clothes and start the dryer immediately. Don't overload the dryer and don't bury the sheet in the middle of the load. Dryer sheets should not be used when you are using air fluff or low heat.
For liquid softener, dilute with an equal amount of warm water before adding to the washer to help disperse the liquid. If your machine has an automatic dispenser, clean it out regularly by flushing with hot, hot water. You'll be amazed at the clumps that will fall out. It's those clumps that stain your laundry!
If you never use fabric softener or dryer sheets but still have these spots, there are a couple of other explanations. One, your washer could be spraying transmission fluid or bearing oil. You can determine if this is the cause by opening the housing of the washer and looking for a fine spray of oil. And, of course, get the problem repaired.
If the problem continues even with a new washer, the problem could be a reaction between your water and the detergent you are using. Try switching to a heavy duty detergent like Wisk or Tide (Original formula) and use the hottest water recommended for each type of fabric.
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