Abstract: A fire suppressant system is provided for a vehicle having a body and a fuel tank mounted to the rear end of the body and rearwardly of a rear axle differential. The fire suppressant system comprises an elongated cylindrical housing defining a closed interior chamber which in turn is filled with a pressurized liquid fire suppressant material. The housing is secured to the vehicular body in between the front end of the fuel tank and the rear axle differential so that forward displacement of the fuel tank, as would occur in the event of a rear end collision, contacts and breaks the housing thereby releasing the fire suppressant material which ejects onto and over the fuel tank. In a modified form of the invention, an elongated housing defining a closed interior chamber is filled with a pressurized fire suppressant material mounted onto the top of a fuel tanker truck.