TF80SC Generation 2 Transmission: Overview

Overview

Automatic transmission TF80SC Generation 2





Hint: The shape of the transmission casing differs depending on which engine is included in the driveline.

This transmission has been updated on several points to meet high demands for fuel economy and comfort. TF80SC Gen 2 replaces earlier versions of TF80SC.
Changes compared to earlier version:
- Solenoids
- tapered bearings
- friction pads
- Seals
- oil with lower viscosity
- "lock-up" at lower engine rpm
- software in TCM ( Transmission Control Module)
- fastening AC bracket (6-cyl. engines)
These changes contribute to lower internal losses and, together with upshifting at lower engine rpms, faster downshifts, the result is lower fuel consumption, better shifting quality, and higher efficiency.
TF-80SL (TF-80SL AWD) is an electronically controlled 6-speed automatic transmission with Geartronic.
The Geartronic function combines two transmissions in one. One adaptive 6-gear automatic transmission which enables relaxed driving, and a "manually" shifted transmission which enables more active driving with manual shifting. In case of manual shifting, the gear selector is pushed forward to upshift to a higher gear and it's pulled back to downshift to a lower gear. However, in certain situations the Transmission control module (TCM) assumes the gearshifting decisions. For more information about shifting with Geartronic, see Design and Function, Transmission control module (TCM).
TF-80SL has a lock-up-function on all forward gears except 1st gear. The torque converter has a locked and slipping lock-up-function.
Gearshifts are controlled by an hydraulic operating system. Gearshifts take place without freewheeling and completely automatically in terms of load and speed.
TF-80SL has two planetary gear units, a front and a rear, whose shifts are controlled by a number of clutches and brakes. The rear planetary gear is of the Ravigneaux type.
The oil level is checked by level pipe (the transmission does not have a conventional dipstick).
The transmission has a total of 8 solenoids that control the hydraulic flow. 6 of these solenoids control the shift process, 1 solenoid controls the torque converter's lock-up function and 1 solenoid controls the system pressure.
The gear selector sensor is integrated in the Transmission control module (TCM). The Transmission control module (TCM) is integrated in the transmission. For information about the Transmission control module (TCM), solenoids and sensors, see Design and function, Transmission control module (TCM).