Abstract: A wheel adapter is provided which enables dual or tandem wheels to be attached to the hub of a vehicle axle which has been designed for a single wheel. The wheel adapter includes an elongated housing having an annular mounting flange at one end and a plurality of axially aligned, circumferentially spaced tubular members at its other end which register with the outwardly protruding studs from the wheel hub. A plurality of nut members threadably engage the studs on the wheel hub to secure one wheel rim to the hub. The other end of each nut member is cylindrical and extends into one of the tubular members while cooperating conical surfaces on the nut member and one end of the tubular members abut together. A bolt extends through the other end of each tubular member and threadably engages a bore in the cylindrical end of the nut member.