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Gearbox

Gearbox


The automatic transmission has 3 planetary gear trains with clutches, brakes and freewheel. It has twin shafts (primary and secondary shafts). Two of the 3 planetary gear trains, P1 and P2, constitute the primary shaft of the gearbox. The rear planetary gear train (P1) is a single planetary gear and the front (P2) has two sets of planet wheels. The outer one comprises the short planet wheels and the inner of the long ones. The inner planet wheel and the sun gear shaft are common to both 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 gearbox has 4 forward gears and one reverse.

There is normally some degree of slippage in the torque converter. This slippage is proportional to the increase in torque that is generated. To reduce fuel consumption, a Lock-up clutch in the torque converter eliminates the slippage in 3rd and 4th gears when it is engaged by providing direct drive through the converter.