TouchShift is a manual shift function used in automatic transmissions from Mercedes-Benz Benz models is included. It was introduced in the late 1990s. It allows the rider to control shifting, which is useful when going downhill or uphill, accelerating, turning and starting on slippery surfaces.
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How TouchShift works
The TouchShift function is used in standard automatic transmissions equipped with a hydraulic torque converter and planetary gear sets. It works via a special firmware that can engage the gear selected by the driver. The mode can be set to manual shifting by briefly moving the shift lever from the “D” position to the “D+” or “D-” position. The activated mode and the set speed are then displayed on the instrument panel screen. At very high speeds, the system will not downshift to avoid damaging the engine.
Popular transmissions with TouchShift functionality
| Index | Number of gears | Max. Displacement, l | Max. Torque, Nm | Type of drive | Year of manufacture | Applicable Mercedes Benz models |
| 722.6 | 5 | 3.5 | 350 | Rear, 4WD | 1995 | S Class W140; C Class W202; E Class W210; C Class W203; S Class W221; C Class W204; E Class W212; E Class W211; S Class W220; M-Class W163 |
| 722.7 | 5 | 1,9 | 205 | Front wheel | 1998 | A-Class W168; Vaneo W414 |
| 722.9 | 7 | 6,3 | 850 | Rear, 4WD | 2003 | S Class W220; C Class W205; E Class W212; C Class W204; E Class W211; M Class W164; S Class W221; M-Class W166 |
Frequent defects of gearboxes with TouchShift
| Defects | Transmission |
| The bushing mounted between the transmission shafts has a short service life. | 722.6 |
| The one-way clutch breaks easily. | 722.6 |
| The transmission's solenoid valves quickly become contaminated. | 722.6 |
| The torque converter solenoid fails prematurely. | 722.6 |
| The circuit board quickly becomes inoperable. | 722.6; 722.7 |
| The clutch drum often fails. | 722.7 |
| The circuit board fails quickly. | 722.9 |
| The gearbox housing is damaged by excessive vibration . | 722.9 |
| The servo module fails. | 722.9 |
