The gearbox, which is called 4F27E by its creators, is a new development that appeared with system support «Mazda» - a subsidiary of Ford, specifically for use in the Focus. 4F27E means: 4 - four-speed transmission, F - front-wheel drive, 270 lb.ft (365 Nm) - maximum torque at the input after the torque converter, E - Electronic (fully electronically controlled). The new automatic transmission works with a clutch to lock up the torque converter and overdrive (boosting) transmission at the push of a button. Two sequentially shifted sets of planetary gears realize the corresponding transmission ratios - three multi-plate clutches, a friction brake, a brake band, and a freewheel roller clutch perform the functions of drive or braking. The drive torque passes through the intermediate gear stage before it reaches the final drive.
Design and function of the 4F27E gearbox: 1 - brake band 2nd / 4th gear; 2 - sets of planetary gears; 3 - reverse gear brake; 4 - clutch 1st - 3rd gear; 5 - oil pump with torque converter reactor assembly; 6 - torque converter; 7 - input shaft of the gearbox; 8 - differential; 9 - intermediate gear stage; 10 - output gear - automatic transmission; 11 - 1st gear freewheel; 12 - reverse clutch; 13 - clutch 3rd - 4th gear.
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