A mounting arrangement for adding an auxiliary wheel spaced from an existing wheel of a motor vehicle including two or more generally cylindrical spacers connected together abutting end to end, an inner spacer attached to a brake assembly member with a preexisting wheel rim compressed between an inside face of the inner spacer and the brake assembly member, and an outer spacer connected to the inner spacer by bolts, and holding stud bolts extending out and received through holes in the auxiliary wheel rim, with lug nuts fixing the rim of the auxiliary wheel against the outside end of the outer spacer. An intermediate spacer between the inner and outer spacers may alternatively be provided detachably connecting the inner and outer spacers together, attached to an outside end of the inner spacer and to the inside end of the outer spacer by bolts.