Self-loosening of bolted connections is a crucial failure mode for joints under transverse dynamic load. For some years, three dimensional finite element analysis has been enabled for avoiding experimental investigations of self-loosening. The aim of this paper is to emphasize the effect of joint design on the self-loosening of bolted connections, which is important for product development in early design stage. Joints consisting of internally threaded nut components are often heavier and stiffer as compared with light weight designs consisting of a separate nut. The difference of self-loosening is significant between arrangements with nut thread component and separate nut, although the design versions only contain slight modifications. Hence it is necessary to evaluate the effect of light weight design on self-loosening.