PURPOSE: To improve the confortableness of a rear tandem car ay forming the front end part of the longest leaf out of plural leaves in a wave shape and avoiding the slip of the contact point of the leaf on an axle by matching the motion of the front end of the leaf with the motion of a rear front axle decided by a torque rod and dissolving the friction force between the axle and the leaf.

CONSTITUTION: A drive wheel 42 and a loose wheel 43 are bounded on a rugged road surface and the rear front axle 40 is elevated around a moment center C1 and the rear rear axle 41 is elevated around the moment center C2 respectively by the bending of their right/left leaf springs 12, 12. At this time, the contact point P1 of the leaf 17, 17 contacted to the rear front axle 40 moves along the locus L'1 around the locus center O1 and does not interfere to the locus L1 of the contact point P1 around the moment center C1 of the rear front axle 40. Namely, the slip of the contact point P1 of the leaf 17, 17 is avoided on the rear front axle 40 and the friction force generated on the contact part of the rear front axle 40 with the leaf 17, 17 is dissolved.