6-Speed Automatic Transmission: Introduction
The 6-speed automatic transmissions were jointly developed by BMW and ZF (Zahnradfabrik Friedrichshafen).
- See appropriate AUTOMATIC TRANSMISSIONS OVERVIEW article.
The automatic transmission is either standard or optional equipment (option 205).
So as to be compatible with the engines with higher torques, the automatic transmissions are designed with different strengths. The automatic transmissions thus differ, e.g. through different torque converters.
Depending on the engine fitted, the following 6-speed automatic transmissions are fitted:
- GA6HP19Z (designed for maximum torque of 420 Nm)
- GA6HP26Z (designed for maximum torque of 600 Nm)
- GA6HP32Z (designed for maximum torque of 750 Nm)
The automatic transmission requires 5 multi-plate clutches to shift between the 6 gears: 3 input clutches and 2 brake clutches.