We performed fatigue tests by using full-scale axles on which numerous artificial flaws were incised at their wheelseats. The tests were performed in order to reconsider the inspection system for narrow-gauge line vehicle axles. The axles that were tested at a nominal stress of 80 MPa developed fractures at the wheelseat due to the propagation of fretting fatigue cracks. On the other hand, axles that were tested at the nominal stress of 60 MPa did not fracture, even at the maximum number of cycles of 5.4 × 107. In the case where the maximum service stress does not exceed 60 MPa, it is possible to reduce the inspection work to only when wheels are renewed.