PRELOAD INSPECTION METHOD FOR BEARING DEVICE FOR VEHICLE WHEEL.

Provided is a preload inspection method with which a preload value can be calculated more accurately. Furthermore, provided is a preload inspection method with which a pass/fail with regard to a preload state can be determined more accurately. The preload inspection method for a wheel bearing device (1) provided with an outer member (2) having an outside raceway surface (2c/2d), an inner member (3) having an inside raceway surface (3c/3d), and rolling bodies (4/5), is provided with: a power calculation step (S5) in which the outer member (2) or the inner member (3) is rotated in a relative manner and the power (P) is calculated; a preload value calculation step (S6) in which a preload value (F2) is calculated on the basis of the power (P) calculated in the power calculation step (S5); and a pass/fail determination step (S7) in which a pass/fail determination is made on the basis of whether the preload value (F2) calculated in the preload value calculation step (S6) is within a permissible range (R).