Forward Clutch Assembly
Forward (1, 2, 3, 4) Clutch Exploded View
| Item | Description |
|---|---|
| 1 | Low One-Way Clutch (OWC) snap ring |
| 2 | Low One-Way Clutch (OWC) |
| 3 | Forward clutch friction plates |
| 4 | Forward clutch steel plates |
| 5 | Forward clutch waved cushion spring |
| 6 | Forward clutch piston snap ring |
| 7 | Forward clutch piston return spring |
| 8 | Forward clutch piston |
| 9 | Front sun gear and shell assembly |
| 10 | Transmission case |
Forward (1, 2, 3, 4) Clutch Mechanical Operation
The forward clutch is a brake clutch that holds the front sun gear and shell assembly. The forward clutch is applied in 1st, 2nd, 3rd and 4th gear.
Hydraulic pressure from the regulator valve in the valve body pushes the forward clutch piston against the forward clutch pack to apply the clutch. The forward clutch pack is pushed against the low One-Way Clutch (OWC) when it is applied. The rear sun gear and shell assembly is held stationary to the transmission case as a result of the clutch being applied.
Forward (1, 2, 3, 4) Clutch Hydraulic Circuits (Applied in 1st, 2nd, 3rd and 4th Gear Above 8 km/h [5 mph])
When the forward (1, 2, 3, 4) clutch is applied in 1st (above 8 km/h (5 mph), 2nd, 3rd and 4th gears, LINE pressure from the pump is directed to the multiplex shift valve by the manual valve through the DRIVE 1 hydraulic circuit. The multiplex shift valve supplies the forward (1, 2, 3, 4) clutch regulator valve with pressure through the DRIVE 2, CB26FD/CB1234FD and CB1234 SUP hydraulic circuits. The forward (1, 2, 3, 4) clutch regulator valve directs regulated pressure to the forward (1, 2, 3, 4) clutch through the CB1234 hydraulic circuit.
Forward (1, 2, 3, 4) Clutch Hydraulic Circuits (Applied in LOW and 1st Gear Below 8 km/h [5 mph])
When the forward (1, 2, 3, 4) clutch is applied in LOW position and 1st gear below 8 km/h (5 mph), LINE pressure from the pump is directed to the multiplex shift valve by the manual valve through the DRIVE 1 hydraulic circuit. The multiplex shift valve directs the pressure to the multiplex manual valve through the REV DRIVE B circuit. The multiplex manual valve directs the REV DRIVE B pressure to the forward (1, 2, 3, 4) clutch regulator valve through the DRIVE B, CB26FD/CB1234FD and CB1234 SUP circuits. SSA supplies varying solenoid pressure to the CB1234 clutch regulator and boost valves. As the CB1234 clutch regulator valve moves, it supplies the forward (1, 2, 3, 4) clutch and CB1234 boost valve with regulated line pressure through the CB1234 circuit. The CB1234 boost valve directs the regulated line pressure to the opposite side of the regulator valve through the CB1234 FDBK circuit for controlled forward (1, 2, 3, 4) clutch engagement.
For details on valve body hydraulic circuits and solenoid operation.For additional information, refer to: Transmission Description - System Operation and Component Description .