A communication system for vehicles includes a first communication device disposed at a trailer and a second communication device disposed at a vehicle. The communication device wirelessly transmits a communication to the second communication device, and the second communication device receives the transmitted communication from the first communication device. Responsive to processing of the transmitted communication received by the second communication device, the communication system determines an angle of the trailer relative to the vehicle. The first and second communication devices may include first and second dedicated short range communication devices. One of the devices may include spaced apart antennae, whereby the system may determine the angle of the trailer via triangulation based on an antenna of one of the communication devices and the spaced apart antennae of the other of the communication devices.