Transmission and Drivetrain: Service and Repair

Automatic Transmission Remove / Replace, Transmission Model 722.4







Negative cable at battery:
- Disconnect, connect.

Bracket (28):
- Unscrew at cylinder head, screw on.

Control pressure cable (98):
- Press off ball socket, take out retaining element (20) if necessary, detach and attach control pressure cable.
- Adjust cable (27-110).

Engine compartment panelling (30):
- Unscrew, screw on.

Oil from transmission and torque converter:
- Drain, pour in oil after repair, check and adjust to correct level (see Service Manual operation no. 2710). Drain plugs (2 and 3) 14 Nm.

Bolts (17) of torque converter driver plate:
- Unscrew, screw in (6 pieces), 42 Nm.

Crossbar (22):
- Remove and install together with rear engine mount.

Exhaust support (24):
- Unscrew and screw on.

Flexible coupling (25):
- Unscrew and screw on at transmission joint flange.
Note:
- Loosen the flexible coupling on the transmission side with a drift.

Exhaust system:
- Detach and attach at rear mount.
Important:
- Ensure that the component compartment wall and water hoses are not damaged when lowering the exhaust system. (numbers 1, 2).

Propeller shaft clamping nut (7):
- Loosen and push propeller shaft together as far as possible.
- Tightening torque 30-40 Nm.

Cable (6) of kick-down solenoid valve and pulse generator or speedometer shaft (23):
- Detach, attach.
Installation note:
Ensure correct installation

Shift rod (9):
- Detach and attach at range selector lever.

Plug (8) for starter lock-out switch:
- Press off and on by turning circlip upwards.
Vacuum lines:
- Detach and fit on.
Note:
Vacuum unit: White
Selector program: Red
Shift point retard: Black/green

Oil filter pipe (15):
- Push out and in by loosening bolt (14) and bracket.

Supply and return line of oil cooler (12, 13):
- Detach, attach, replace seals.

Transmission (1):
- Raise, unscrew and screw in all bolts on the converter housing except the two bolts (21), M10=55 Nm.
- Pull out and push in transmission horizontally with torque converter.
Installation note:
Ensure that the dowel pins are properly seated.

Torque converter:
- Pull out and insert by removing plastic retaining pin and installing handles.
Note:
Ensure correct installed height of the torque converter in the transmission housing (number 3).
Installation note:
- Grease drive flange (32) with Molykote. When inserting torque converter, turn backwards and forwards to ensure that teeth mesh properly.
- Insert plastic retaining pin and turn 1/4 turn clockwise.


Torque converter:
- Check (number 4, 5)

Oil cooler with oil cooler line and torque converter:
- Flush (numbers 6, 7, 8)

Special tools:































Removal and installation:

1. To avoid damaging the component compartment wall, a 300 x 300 mm metal sheet must be inserted as a protection for the insulation matting on the component compartment wall, when performing any work which involves lowering the transmission at the rear. Detach exhaust system at rear mount and secure approx. 50 cm lower down with a wire.






Note:
2. In vehicles fitted with auxiliary heater, ensure that water hose (arrow) is not damaged when lowering the transmission.






3. Checking installed height of torque converter in transmission housing:
- Measure the distance "A" between the transmission housing and converter fixing using a depth gauge.

Engine Distance
111 9,6 mm
all diesel engines 8,7 mm
Note:
If the torque converter is not positioned correctly in the transmission housing, this results in irreparable damage to the torque converter and the primary pump.






4. Testing torque converter:
- Excessive engine speeds which can result in damage to the engine due to overspeeding can also cause a permanent expansion of the torque converter. This therefore fouls the primary pump and damages its radial sealing ring.
- Each time the engine is damaged by overspeeding the overall height of the torque converter must therefore be measured.

5. Measuring torque converter:
- Place torque converter with the primary pump drive flange downwards on a measuring plate and measure distance "A".
- If the dimension "A" is less than 121.5 mm the torque converter can be reused, but it should be replaced if the measured value is higher.
Note:
If it is necessary to replace the torque converter, the radial seal on the primary pump must be replaced at the same time.











6. Flushing the torque converter:
- If the transmission oil smells scorched or is contaminated with lining abrasion and/or metal swarf, the torque converter, oil cooler lines and oil cooler must be flushed.

7. Fill torque converter half full with automatic transmission fluid. Insert flushing mandrel (63) and drive at low speed for approx. 2 minutes using a hand drill. Then allow the automatic transmission fluid to drain out through the drain plug using a clean cloth. If there is metal swarf on the cloth, the torque converter must be replaced.






8. Screw oil cooler with oil cooler lines (49) onto the syringe (064) and flush out with automatic transmission fluid; at the same time ensure the transmission oil flows freely. Then blow out oil cooler and oil lines with compressed-air.