D40 may refer to: Akaflieg Darmstadt D-40, a German sailplane D40 Navara, a Nissan pickup truck D40 road (Croatia) Dupuy D-40, a French monoplane , a Ruler-class escort carrier of the Royal Navy LNER Class D40, a class of British steam locomotives New Flyer D40, a Canadian bus Nikon D40, a digital camera