Jeep Cherokee

 Service Manual

Transmission and transfer case » Automatic transmission-30RH » Description and operation
Oil pump

DESCRIPTION

The oil pump (Fig. 17) is located in the pump housing inside the bell housing of the transmission case.

The oil pump consists of an inner and outer gear, a housing, and a cover that also serves as the reaction shaft support.

Fig. 17 Oil Pump Assembly

1 - OIL SEAL
2 - OIL PUMP BODY
3 - VENT
4 - REACTION SHAFT SUPPORT
5 - INNER ROTOR
6 - OUTER ROTOR
7 - "O" RING

OPERATION

As the torque converter rotates, the converter hub rotates the inner and outer gears. As the gears rotate, the clearance between the gear teeth increases in the crescent area, and creates a suction at the inlet side of the pump. This suction draws fluid through the pump inlet from the oil pan. As the clearance between the gear teeth in the crescent area decreases, it forces pressurized fluid into the pump outlet and to the valve body.

30RH automatic transmission

Fluid

Torque converter

Oil pump

Valve body

Accumulator

Pistons

Front clutch

Rear clutch

Overrunning clutch

Planetary gearset

Bands

Servos

Governor

Gearshift mechanism

Converter drainback valve

Brake transmission shift interlock mechanism