Differential distributed space-time coding (DDSTC) has been proved to be suitable for wireless relay networks, since it can provide spatial diversity without the need for channel state information at neither the transmitter nor the receiver side. However, DDSTC suffers from significant error floor in fast-fading channel conditions with high Doppler frequencies due to rapid time variations. For this reason, multiple-symbol differential detection (MSDD) has been proposed in the past, where the detection process involves a larger window size of the received symbols. So far, differential detection for vehicle-to-vehicle (V2V) networks has been studied only for single Rayleigh channels. However, experimental and theoretical studies report that double Rayleigh can be considered as an appropriate fading channel model for V2V networks. In this paper, we assess the error performance of a DDSTC scheme operating in a V2V network using MSDD. Simulation results confirm that the error performance of such a system can be improved significantly with MSDD under different channel time-variation scenarios.