I have managed a laundromat for over 15 years now, and we offer a wash dry fold service to others that either don't have time to do their own laundry, don't know how to do laundry, and some just simply hate the chore of washing and folding clothes. The best way to remove grease is by using Dawn dish liquid, or bar soap. These two products were made to fight grease. Simply cover the stain, and rub the material together to work it in and let sit for an hour or more. Wash as recommended, and the stain should be gone. If it's not gone, do not dry the clothing or it will set the stain making it almost impossible to remove. Just repeat the process again until the stain is out.