A machine for producing a corrugated wheel spacer for use between tandem truck wheels includes top and bottom corrugated rollers which are driven in synchronism with an annular spacer blank therebetween to corrugate the blank. The top roller is suspended from a carriage for vertical movement towards and away from the bottom roller so that an annular blank can be placed on the bottom roller when the rollers are spaced apart and the rollers can be moved together to effect a corrugating operation.