Manual Third Gear
In this range, the forward, direct and overrun clutches are applied; the 4th and converter clutches are released and the transmission is in Manual 3rd gear-direct drive.In manual 3rd ear, the converter clutch is released by the engine vacuum switch and there is no M.V. up or down pressure. However, if the throttle is opened sufficiently, the converter clutch may engage and the M.T.V. up and down valves could open.
A forced 4-3 downshift can be obtained by moving the selector lever from Drive (D) range to third (3rd) gear.
When the selector lever is moved to the 3rd gear position, line pressure is blocked from the RND4 passage and Drive 3 oil from the manual valve is directed to the 4-3 control valve, opening it, while closing the 3-4 shift valve. This allows 4th clutch and accumulator oil to pass back through the 3-4 shift valve and exhaust at the 4-3 control valve. Drive 3 oil also passes through an orifice and applies the overrun clutch to keep the overdrive roller clutch from overrunning when engine braking is needed.