Gearbox TF-81SC

Courtesy of VOLVO CARS CORPORATION

The TF-81SC is an electronically-controlled 8-speed automatic gearbox developed together with Aisin AW.

By using eight gears, the engine can work with a load where the efficiency is at its highest. Engine speed can be kept low, which results in low fuel consumption and thereby also low CO2 emissions.

The gearbox is available in two basic versions designed for engines with different maximum torques.

The version designed for engines with a maximum torque of 350 Nm (B4204T11/T12/T15) has fewer discs and shafts as well as a smaller diameter compared with the version for engines with a maximum torque of 400 Nm (B4204T9/T10, D4204T5). However, the gearboxes have the same planetary gears and control systems.

The design of the torque converter and carrier plate differs between the gearbox designed for petrol engine and the gearbox designed for diesel engine.

Oil-filled gearbox with torque converter (not AWD) weighs approx. 95 kg.

Gear ratios 

The gear ratio between gearbox and intermediate shaft is between 0.804 and 0.902. A number of additional variants are available, depending on the engine/gearbox combination.

The gear ratio between intermediate shaft and differential is either 3.188 or 3.533.