Hydraulic System

Hydraulic System


Pump Assembly and Transmission Fluid Filter

This transmission has a gear type pump that supplies transmission fluid pressure to the hydraulic system.

The inner (drive) gear is turned by the torque converter hub.

The transmission fluid pump has the following parts:

- Pump body, with inner (drive) and outer (driven) gears
- Centering plate
- Intermediate plate
- Stator shaft

The transmission fluid pump draws transmission fluid from the sump area, formed by the transmission fluid pan, through the transmission fluid filter, which is installed into the intermediate plate portion of the pump assembly and sealed by a rubber seal. A magnet attached to the transmission fluid pan collects any magnetic foreign material in the transmission fluid.

Pump Assembly and Transmission Fluid Filter Components










Transmission Fluid Level Indicator

A removable dipstick-type fluid level indicator is located on the right front area of the transmission case. It is held in by an external fluid fill plug. The transmission fluid level indicator is removed with the transmission fluid fill plug. The transmission fluid level indicator is removed from the fill plug to check the transmission fluid level.

The transmission fluid level is correctly checked when the transmission is at normal operating temperature, 80°C-85°C (175°F-185°F), and the vehicle is on a level surface.

The correct transmission fluid level is at the upper level of the crosshatch marks on the transmission fluid level indicator.

Transmission Fluid Level Indicator










Main Control (Mechatronic) Assembly

The hydraulic system of this transmission includes the fluid pump, a main control, or mechatronic assembly and fluid passages in the transmission case and center support to apply the clutches.

The main control assembly has an upper valve body assembly, a separator plate and a lower valve body assembly. The lower valve body assembly has 7 solenoids to control the valves in the main control.

The Transmission Control Module (TCM) is part of the mechatronic assembly and is bolted to it. The Turbine Shaft Speed (TSS) sensor, Output Shaft Speed (OSS) sensor, Transmission Range (TR) sensor and the Transmission Fluid Temperature (TFT) sensor are all part of the TCM.

Mechatronic Assembly