What is the difference? A rebuilt: replacement part, engine, transmission or differential means the unit has been disassembled and the "wear" items have been replaced such as bearings, brushes or guides etc. A rebuilt part will sometimes have individually painted parts. A refurbished unit is basically cleaned, painted and then resold. Obviously you are better off with the rebuilt unit than refurbished, some repair facilities will try to pass the refurbished unit off as a rebuilt unit so be sure you are getting what you ask for. If you are unsure of the integrity of the repair shop ask to see the part or unit before it is installed. Most dealerships and high end repair shops will only install new parts. New parts are optimum for best performance and longevity, rebuilt is the next best thing. You should only agree to a refurbished replacement part as a last resort.