right tubular longitudinal member 12 is right tubular bumper support 18 said fit being snug enough to prevent rattling but loose enough to permit forward and backward movement of the bumper supports 17 and 18 within the members 11 and 12 lubrication with grease facilitates such movement the front bumper is attached to the bumper supports 17 and 18 by hinges 20 and 21 which allow hinge motion on a horizontal axis but not on a vertical axis the hinges 20 and 21 are movably attached to bumper 19 in a manner that allows lateral sliding motion of hinges 20 and 21 relative to bumper 19 hinge stopper 22 attached to bumper 19 prevents hinges 20 and 21 from being moved towards each other during a collision a prestressed cable 23 anchors right hinge 21 to the left end of front cross member 13 and a similar cable 24 anchors left hinge 20 to the right end of front cross member 13 said cables prevent sideward displacement of front bumper 19 and sideward bending deformity of tubular bumper supports 17 and 18 during an offset frontal collision yet these cables do not impede the rearward telescoping motion of the bumper supports 17 and 18 through the tubular longitudinal members 11 and 12 of the chassis 2 the tubular bumper supports 17 and 18 extend substantially forward from the front end of chassis 2 and extend rearward from the rear end of chassis 2 as well rear bumper hinges 25 and 26 attach rear bumper 27 to the rear ends of tubular bumper supports 17 and 18 in a manner similar to the hinged attachments of front bumper 19 rear bumper leaf spring 28 is fixed to the rear bumper 27.