Patent attributes
In a property correcting system of an automatic transmission according to the present invention, a difference of revolutions between input revolutions Nin of a torque converter and turbine revolutions Nt is compared with target rotational difference ΔN, and is increased/reduced by the feedback operation (S6 and S7). It is checked to see if the difference of revolutions is converged to the target rotational difference ΔN (S8). When a driving duty duty which is converged to the target rotational difference ΔN is within a shipping determining standard, the value is stored (S10). A differential value between the stored driving duties duty of the respective automatic transmissions and the reference value is written to a TCU, as the amount of correction of the respective automatic transmissions, thereby correcting the variation in properties of the individual automatic transmissions, starting from the initial shipping timing. A preferable shift quality is obtained without prompting the learning based on the actual driving.