Abstract: A tip-over warning system for vehicles of the articulated type utilizes a swinging pendulum pivoted in a frame which is mounted on and simulates the stability triangle of the vehicle. The pivotal connection of the pendulum is at a scale distance relative to the frame corresponding to the location of the vehicle center of gravity. The side arms of the frame are variable in length and pivoted, allowing the apex of the frame to move. The apex is moved by a servo motor in accordance with the steering angle of the vehicle. The pendulum and frame are connected in an electrical circuit including a current source and an alarm device. When the pendulum touches a side arm of the frame the circuit is completed, thus energizing the alarm device.