Transmission General Description: Notes

The AF 40-6 automatic gearbox is an electronic, 6-speed automatic gearbox with lock-up function. The gearbox is fitted directly against the engine and has a final drive gear with integrated differential. The power unit is transverse mounted with all-wheel drive. Gear positions P-R-N-D are selected with the selector lever mounted in the centre console. Manual up/downshifting is possible.

A special automatic transmission fluid must be used. The transmission does not have an oil dipstick. The plug has an extra center plug to check the level. It is connected to a rising tube that leads to the right level in the gearbox. Fill the oil through the conventional oil filler plug until the level is correct and oil runs out of the check plug hole in the rising tube. Measure the temperature when checking the level. The temperature is read using a scan tool.

The AF 40-6 gearbox has planetary gears, disc clutches, brakes and torque converter with lock-up. The clutches and brakes are operated hydraulically. The hydraulic system is controlled by the Transmission Control Module (TCM) with the help of 8 solenoids, 2 shaft speed sensors and one oil temperature sensor. TCM communicates on the high speed bus.

The TCM is mounted directly on top of the transmission and has one connector to the car's electrical system and one directly to the transmission. The gear position sensor is a Hall sensor and is integrated in the control module. The TCM is mounted so that the selector lever shaft goes through the control module. The selector lever position can be calibrated with the scan tool, there is no mechanical adjustment.

The TCM controls the transmission according to its programming, the information from its own sensors and from other control modules. The control module adapts its control of the solenoids to compensate for normal wear in the transmission. The TCM is SPS programmable.