Can any KitchenAid stand mixer attachments be used to make peanut butter?
The only one that could feasibly handle it would be the grinder. However, in the manual http://www.kitchenaid.com/assets/pdfs/product/ZUSECARE/FGA_Use%20and%20Care_EN.pdf on page 5 it states "Note: Very hard, dense foods such as totally dried homemade bread should not be ground in the Food Grinder. Homemade bread should be ground fresh and then oven or air-dried." If dried, dense bread is too much for the grinder then peanuts would definitely be to much as well. My recommendation is to use a food processor.