Couplings
In a 4-speed automatic transmission, hydraulically driven clutches are used to engage and disengage the automatic transmission gears. When hydraulic pressure is applied to the clutch drum, the clutch piston moves. In this case, the driven friction discs and the leading steel discs are pressed against each other and locked in this state, eliminating slippage. Power is transmitted through the engaged clutch assembly to the gear mounted on the hub. Similarly, when hydraulic pressure is released from the clutch assembly, the piston forces the friction discs apart and the steel plates are able to rotate without interfering with each other. In this case, the gear rotates independently on its shaft and no power is transmitted.
1st gear clutch
The 1st gear clutch, located in the center of the driven shaft, engages and disengages the 1st gear. Hydraulic pressure is supplied to the 1st gear clutch via the ATF supply pipes in the driven shaft.
2nd gear clutch
The 2nd gear clutch, located at the end of the driven shaft opposite the end cover, engages and disengages the 2nd gear. Hydraulic pressure is supplied to the 2nd gear clutch through a circuit connected to the internal hydraulic circuit.
3rd gear clutch
The 3rd gear clutch, located in the center of the drive shaft, engages and disengages the 3rd gear. Hydraulic pressure is supplied to the 3rd gear clutch via the ATF supply pipes in the drive shaft.
4th gear clutch
The 4th gear clutch, located at the end of the drive shaft, engages and disengages the 4th gear pinion as well as the reverse gear pinion. The 4th gear clutch contacts the 3rd gear clutch. Hydraulic pressure is supplied to the 4th gear clutch through a circuit connected to the internal hydraulic circuit.