audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

Rules for cleanliness when working on the gearbox > < Notes on tow-starting and towing
Repair instructions
Repair instructions
Proper tools and the maximum possible care and cleanliness are essential for satisfactory gearbox repairs. The usual basic safety precautions also naturally apply when carrying out repair work.
To avoid repetition, a number of generally applicable instructions for the various repair procedures are summarised here. They apply to the work described in this Manual.
   
Guided Fault Finding, vehicle self-diagnosis and testing system
t  Before servicing the gearbox, the exact cause of the failure must be determined using the functions “Guided Fault Finding”, “Vehicle Self-diagnosis” and “Test Instruments” → Vehicle diagnosis, testing and information system VAS 5051.
Environmental and waste disposal regulations for oil
t  ATF, gear oil and any other type of oil must be handled with care.
t  Dispose of drained oil properly.
t  Always adhere to statutory environmental and waste disposal regulations.
t  Observe the information shown on the packaging of the oil.
Special tools
For a complete list of special tools used in this Workshop Manual → "Special tools, Workshop equipment"
Gearbox
t  Observe rules for cleanliness when working on gearbox → Chapter.
t  The engine must not be run and the vehicle must not be towed if the centre differential housing has been removed or if there is no ATF in the gearbox.
t  After installing, the following fluid levels must be checked and topped up if necessary: ATF in gearbox → Chapter and gear oil in gearbox → Chapter. Capacities and specifications → Chapter
O-rings, oil seals and gaskets
t  Always renew O-rings, oil seals and gaskets.
t  After removing gaskets and seals, always inspect the contact surface on the housing or shaft for burrs resulting from removal or for other signs of damage.
t  Thoroughly clean housing joint surfaces before assembling.
t  Lightly lubricate the outer circumference and sealing lip of oil seals with ATF before installing.
t  Lightly lubricate O-rings with ATF before installation to prevent them from being crushed during assembly.
t  Use only ATF for parts running in ATF. Other lubricants will cause malfunction of the gearbox hydraulics.
t  The open side of the oil seal should face the side containing the fluid.
t  When installing a new oil seal, position the seal such that the sealing lip does not contact the shaft in the same place as the old seal (make use of installation depth tolerances).
t  After installing, the following fluid levels must be checked and topped up if necessary: ATF in gearbox → Chapter and gear oil in gearbox → Chapter. Capacities and specifications → Chapter
Nuts, bolts
t  Loosen bolts in reverse sequence to the specified tightening sequence.
t  Bolts and nuts used to secure covers and housings must be tightened in steps according to the specified tightening sequence and method.
t  Nuts and bolts which secure covers and housings should be loosened and tightened in diagonal sequence and in stages if no tightening sequence is specified.
t  Renew self-locking nuts and bolts.
t  Use a wire brush to clean the threads of bolts which are secured with locking fluid. Then apply locking fluid -AMV 185 101 A1- to bolt threads before installing.
t  Threaded holes which take self-locking bolts or bolts coated with locking fluid must be cleaned (using a tap or similar). Otherwise there is a danger of the bolts shearing off the next time they are removed.
t  The tightening torques stated apply to non-oiled nuts and bolts.
Locking elements
t  Do not over-stretch circlips.
t  Renew circlips which have been damaged or over-tensioned.
t  Circlips must be properly seated in the base of the groove.
Bearings
t  Install needle bearings so the lettering (side with thicker metal) faces towards the installing tool.
t  Lubricate bearings with gear oil or ATF, depending on fitting location.
t  Do not interchange inner or outer races of bearings of the same size.
t  Always renew the tapered roller bearings on one shaft together and use new bearings from a single manufacturer.
Shims
t  Use a micrometer to measure the shims at several points. Tolerance variations make it possible to obtain the exact shim thickness required.
t  Check for burrs and damage. Install only shims which are in perfect condition.
  W00-10343

Rules for cleanliness when working on the gearbox > < Notes on tow-starting and towing