Mechanical Components and Functions: Lubrication: Notes

Transmission fluid enters the lubrication circuits after flowing through the transmission fluid cooler. The transmission fluid cooler is mounted at the front of the vehicle. When the transmission fluid is not up to operating temperature, an internal thermal bypass valve allows the transmission fluid to bypass the transmission fluid cooler. When the transmission fluid circulates through the transmission fluid cooler, the transmission fluid returns to the transaxle from the transmission fluid cooler tubes through the back transmission fluid cooler tube.

The transmission fluid enters main lubrication circuit through the transaxle case and flows through passages in the input shaft to lubricate the transaxle.

The transmission fluid in the input shaft circuit flows from the back of the input shaft toward the front of the input shaft and passes through ports in the input shaft to lubricate the planetary gearset, clutches, final drive assembly and other components of the transaxle.

Fig 1: Identifying Thermal Bypass Valve Assembly And Transmission Fluid Cooler Return Tube Fitting

Courtesy of FORD MOTOR CO.