my mom drives a 93 ford explorer, tonight it was starting to shudder and act crazy when we were driving it. when it was in gear it would rev really high and not move anywhere, when it was put into reverse it would go backward, then in differerent gears it would start rolling backward. i think it could be the transmission but it was driving fine all day, we put some transmission fluid in the car and it seemed to work better for a min, then it started acting crazy again. also the radiator fluid was a brownish orange color. i hope the transmission didnt just go out, but i need another opinion. thanks alot