## Automatic Transmission

#### System Description (cont'd)

14-26

Clutches

The 4-speed automatic transmission uses hydraulically-actuated clutches to engaged or disengage the transmission gears. When hydraulic pressure is introduced into the clutch drum, the clutch pistoNmoves. This presses the friction discs and steel plates together, locking them so they do not slip. Power is then transmitted through the engaged clutch pack to its hub-mounted gear. Likewise, when the hydraulic pressure is bled from the clutch pack, the piston releases the friction discs and the steel plates and they are free to slide past each other. This allows the gear to spin independently on its shaft, transmitting no power.

1st Clutch

The 1st clutch engages/disengages 1st gear and is located at the end of the mainshaft, behind the end cover. The 1st clutch is supplied hydraulic pressure by its ATF feed pipe within the mainshaft.

2nd Clutch

The 2nd clutch engages/disengages 2nd gear and is located at the middle of the mainshaft. The 2nd clutch is joined back-to-back to the 4th clutch. The 2nd clutch is supplied hydraulic pressure through the mainshaft by a circuit connected to the internal hydraulic circuit.

3rd Clutch

The 3rd clutch engages/disengages 3rd gear and is located at the end of the countershaft, opposite the end cover.

The 3rd clutch is supplied hydraulic pressure by its ATF feed pipe within the countershaft.

4th Clutch

The 4th clutch engages/disengages 4th gear, as well as reverse gear and is located at the middle of the mainshaft. The 4th clutch is joined back-to-back to the 2nd clutch. The 4th clutch is supplied hydraulic pressure by its ATF feed pipe within the mainshaft.

1st-hold Clutch (7-position)

The 1st-hold clutch engages/disengages 1st-hold or position and is located at the middle of the sub-shaft. The 1st-hold clutch is supplied hydraulic pressure by its ATF feed pipe within the sub-shaft.

One-way Clutch

The one-way clutch is positioned between the countershaft 1st gear and the park gear. The park gear is splined with the countershaft and rotates with the countershaft. The countershaft 1st gear provides the outer race surface of the one-way clutch and the park gear provides the inner race surface.

The one-way clutch locks up when power is transmitted from the mainshaft 1st gear to the countershaft 1st gear. The 1st clutch and gear remain engaged in the 1st, 2nd, 3rd and 4th gear ranges in the , , or position. However, the one-way clutch disengages when the 2nd, 3rd and 4th clutches and gears are applied in the , or position. This is because the increased rotational speed of the gears on the countershaft overrides the locking ''speed range'' of the one-way clutch. The one-way clutch free-wheels when the 1st clutch is engaged.