Abstract: A step bumper having a hinged door as the step, such door being of sufficient width and height to accommodate and secure a spare tire through. Two attachment extensions are provided for securing the bumper to the main frame members of the vehicle. Support structures are provided in the form of two steel straps attached by one end to a cross member on the underside of the vehicle and to the bumper attachment extensions at the opposite end. The straps are shaped to conform to the shape of a spare tire. The step is hinged to the extensions and releasably held closed by hand operated knob bolts, which extend through holes in each side of the step into corresponding threaded holes, e.g., nuts welded on to the extensions. The tire securing mechanism has an arcuate shape with a reverse hook at one end and a loop structure at the opposite end. The reverse hook fits in a hole in the wheel of the tire, the arcuate shape goes around the tire and the loop is locked to a chain which is affixed to the cross member.