Transmission and Drivetrain: Service and Repair

GENERAL INSTRUCTIONS
The maximum possible care and cleanliness and proper tools are essential to ensure satisfactory and successful transmission repairs. The usual basic safety precautions also apply when performing vehicle repairs.

A number of generally applicable instructions for individual repair procedures, which are otherwise mentioned at various points in the Repair Manual, are summarized here. They apply to this Repair Manual.

TRANSMISSION
When an automatic transmission is exchanged, check the VW ATF in the planetary gearbox page and the VW ATF in the final drive and top up as necessary. Refer to ATF and oil capacities and specifications. Specifications
- During installation, ensure that the dowel sleeves are installed correctly.

GASKETS, OIL SEALS
- Radial shaft seals: Pack space between sealing lips with grease before installing.
- Always install new O-rings.
- After installing check ATF level in final drive or planetary gearbox, adjust to correct level if necessary.

LOCKING ELEMENTS
- Do not overstretch circlips; replace if necessary.
- Circlips must be properly seated in the grooves.

NUTS, BOLTS
- Nuts and bolts for attaching covers and housings must be loosened and tightened in a crosswise pattern.
- Especially delicate components - e.g. valve body - must always be precisely aligned and loosened/tightened in a diagonal patted in several stages.
- The tightening torques stated apply to un-oiled nuts and bolts.
- Threads of bolts that are secured by locking fluid are to be cleaned with a wire brush. Then insert bolts with suitable locking fluid.
- Always replace self-locking nuts.

BEARINGS
- Install needle bearings with the inscribed side (thicker metal) facing the drift.
- Lubricate transmission bearings with gear oil before installing.
- Lubricate components thoroughly for friction torque measurements.
- Heat the inner races of taper roller bearings to approx. 100°C (212°F) before inserting.
- Do not interchange the inner and outer races of same size bearings.
- Always replace taper roller bearings which are mounted on a shaft together and use bearings from a single manufacturer.

SHIMS
- Measure shims at several points with a micrometer. Different tolerances make it possible to obtain the exact shim thickness required.
- Check for burrs and damage. Install only shims which are in perfect condition.

INNER PLATES
- Soak new inner plates in ATF fluid for 15 minutes before installing.

VALVE BODY
- Replace the valve body if any of the selector elements are scorched.

CLUTCHES
- Clutches K1, K2 and K3 should initially be disassembled only for cleaning. If parts are worn or damaged, replace the clutch.

ON BOARD DIAGNOSTIC (OBD)
- Before performing repairs to the automatic transmission, determine the cause of the malfunction as precisely as possible with the aid of the On Board Diagnostic (OBD) capability.