Abstract: A method and apparatus for alternately braking a pair of drive wheels on an automotive vehicle to increase the total tractive effort of thevehicle, by preventing the spinning of a drive wheel which is on ice, in mud, on a slippery spot, and the like. An electric motor is mounted on the vehicle frame in a position near the two parking or emergency brake conventional operating cables. An elongated drive structure interconnects the motor and the brake operating cables to alternately exert tension on one of the cables while releasing tension on the other, and continuing the alternate tensioning of the cables to brake one drive wheel while the other drive wheel remains free to gain traction.