PRELOAD INSPECTION METHOD FOR BEARING DEVICE FOR VEHICLE WHEEL

A preload inspection method with which a preload value can be calculated more accurately. The preload inspection method for a wheel bearing device provided with an outer member having an outside raceway surface, an inner member having an inside raceway surface, and rolling bodies, is provided with: a power calculation step in which the outer member or the inner member is rotated in a relative manner and the power is calculated; a preload value calculation step in which a preload value is calculated on the basis of the power calculated in the power calculation step; and a pass/fail I determination step is made on the basis of whether the preload value calculated in the preload value calculation step is within a permissible range.