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General

General


The automatic transmission consists of three planetary gear trains with clutches, brakes and freewheel. It has twin shafts (primary and secondary shafts). Of the three planetary gear trains, two (P1 and P2) constitute the transmission's primary shaft. The rear planetary gear train (P1) is a single planetary gear train and the front (P2) has a double set of planet gears. The outer one consists of the short planet gears and the inner one of the long planet gears. The inner planet gears and sun wheel shaft are common to P1 and P2.

The secondary shaft consists of planetary gear train P3, which is single.

The power from the primary shaft is transmitted to the secondary shaft via two intermediate gears. From the secondary shaft the power is then transmitted to the final drive via two final drive pinions, one driving and one driven.

The oil pressure in the hydraulic system is created by a built-in oil pump which simultaneously lubricates all moving parts in the transmission.

The transmission's brakes and clutches are controlled by gear-shifting valves which in turn are controlled by the solenoid valves mounted in the valve housing. The transmission can generate four forward gears and one reverse gear.

There is normally some slippage in the torque converter. This slippage is proportional to the increase in torque that it brings about. To reduce fuel consumption, a lock-up clutch on 3rd and 4th gears is used. This clutch eliminates slippage in the torque converter.