The serial number is normally in the master bedroom closet. There will be a piece of paper adhered to the wall of the closet. You will recognize it as the paper has a drawing of the USA on it. The serial number is on that paper. Other locations for the paper would be on the inside of a kitchen cabinet. If the paper has been removed you can find the serial number stamped in to the frame next to where the hitch is or was. More information on serial number location.