Important Information on automatic Car Gearing System for all Car users Very many automatic car users are careless to understand the gearing transmission system of autos. We are aware of ‘P, R, N, D, D1, d2, D3′ or ‘P, R, N, A, 2, 3, L’ in our cars and we understand only P=park, R=reverse, N=neutral and D=drive only. The others’ function are discussed bellow. The d1, d2,