Automatic Transmission Function

Automatic transmission 722.6 is an electrically controlled 5-speed transmission with a lockup clutch in the torque converter.

The ratio for the gear stages are achieved by 3 planetary gearsets. The 5th gear is designed as a low-rev gear with an overdrive ratio.

Shifting is initiated electronically. The gears are shifted by the corresponding combination of 3 hydraulically actuated multi-disc brakes, 3 hydraulically actuated multi-disc clutches and 2 mechanical freewheels.

Both the oil pump and the externally toothed disc carrier of the front multi-disc brake are screwed to the torque converter housing.

The mechanical part consists of the drive shaft, output shaft, a sun gear shaft and 3 planetary gearsets which are coupled together.

The electrohydraulic control unit is screwed onto the transmission housing from below. The end of the transmission is formed by an oil pan made of sheet metal.

The oil pressure of the torque converter lockup clutch and center multi-disc clutch is supplied via bore holes in the drive shaft. The oil pressure to the rear multi-disc clutch is supplied via the output shaft. The lubricating oil is supplied and distributed by additional bore holes bore holes in both shafts. Oil is supplied to all bearing points of the gearsets as well as to the freewheels and shifting elements.

The parking lock gear and drive flange re connected to the output shaft by gearing.

Automatic transmission 722.6 with electronic control offers the following advantages:

• Reduced fuel consumption.
• Greater ease of shifting.
• Favorable spacing by 5 gears.
• Long service life and high reliability.
• Low maintenance costs.

The torque converter housing and transmission housing consists of a light-metal alloy. Both housings are bolted together and are centered via the external plate carrier at the multi-disc brake at the front. A coated intermediate panel seals the two components.

Freewheels F1 and F2 optimize shifting. The front freewheel F1 is supported on the extension of the stator shaft on the transmission end and connects in the locking direction the sun gear of the front planetary set with the transmission housing.

The rear freewheel F2 connects in the locking direction the sun gear of the center planetary set with the sun gear of the rear planetary set.

The electrohydraulic control unit is comprised of a light alloy shift plate for the hydraulic control and an electric control unit.

The electronic control unit consists of a plastic shell which combines all the electric components. The supporting body is mounted on the shift plate and is screwed to it. Conductor tracks which are laid in the supporting body make the connection between the electrical components and a 13-pin plug socket.

1. Automatic Transmission, Location Of Mechanical Components
   
   See AUTOMATIC TRANSMISSION, LOCATION OF MECHANICAL PARTS  .
2. Automatic Transmission, Location Of Electrical/Electronic Components
   
   See AUTOMATIC TRANSMISSION, LOCATION OF ELECTRIC/ELECTRONIC COMPONENTS  .
3. Automatic Transmission, Location Of Hydraulic Components
   
   See AUTOMATIC TRANSMISSION, POSITION OF HYDRAULIC COMPONENTS  .
4. Automatic Transmission, Location Of Components, Floor Shift
   
   See AUTOMATIC TRANSMISSION, LOCATION OF COMPONENTS, FLOOR SHIFT  .
5. Automatic Transmission, Selector Lever Positions
   
   See AUTOMATIC TRANSMISSION, SELECTOR LEVER POSITIONS (EXCEPT CODE (428a) STEERING WHEEL-SHIFT BUTTONS)  or AUTOMATIC TRANSMISSION, SECTOR LEVER POSITIONS (WITH CODE (428a)) STEERING WHEEL SHIFT BUTTONS  .
6. Automatic Transmission, Driver Information
   
   See AUTOMATIC TRANSMISSION, DRIVER INFORMATION (EXCEPT CODE (428a) STEERING WHEEL SWITCH BUTTONS)  or AUTOMATIC TRANSMISSION, DRIVER INFORMATION (WITH CODE (428a) STEERING WHEEL SHIFT BUTTONS)  .
7. Automatic Transmission, Gear Ratios
   
   See AUTOMATIC TRANSMISSION, GEAR RATIOS  .
8. Function Of Power Transmission
   
   See POWER TRANSMISSION, FUNCTION  .
9. Function Of Gear Shift
   
   See FUNCTION OF GEAR SHIFT (EXCEPT CODE (428a) STEERING WHEEL SHIFT BUTTONS)  or FUNCTION OF GEAR SHIFT (WITH CODE (428a) STEERING WHEEL SHIFT BUTTONS)  .
10. Function Of Transmission Control
    
    See FUNCTION OF TRANSMISSION CONTROL  or FUNCTION OF TRANSMISSION CONTROL  .
11. Kickdown, Function
    
    See KICK-DOWN FUNCTION (AS OF 6/1/02)  .
12. Shift Lock, Function
    
    See SHIFT-LOCK, FUNCTION  .