I remember one of the techs I used to bring my machines to, recommend that I bring in my walking foot as they actually do need some cleaning and oiling. I never did but I really don't use my walking foot that heavily as I have a long arm and do most of my quilting on that. I have however over oiled my long arm and had oil dripping down the needle. The manual recommends not parking my longarm head over a quilt when I am not using it for this reason.