Repair Information
Repair Information
For the transmission to be repaired successfully and to function correctly, the greatest possible care and cleanliness and proper tools are required. The usual basic safety precautions also apply when carrying out vehicle repairs.
A series of generally applicable notes for individual repair procedures have been gathered here which otherwise would be listed several times in many places in the appropriate repair information. It applies to this appropriate repair information.
Guided fault finding, vehicle diagnosis and test instruments
• Before performing repairs on the transmission, the cause of the malfunction must be determined as accurately as possible in the operating modes " Guided Fault Finding", "vehicle diagnosis, testing and information system" and "Test Instruments".
Transmission
• Do not run engine or tow vehicle with oil pan removed or without transmission fluid.
• Fill the transmission with transmission fluid after performing a repair. Capacities => [ Transmission Capacities ] 086A (R-Tronic) or Manual Shift Transmission.
• When replacing the transmission, check and fill the gear oil. Refer to => [ Oil Drain, Oil Fill and Oil Check Plug Assembly Overview ] Description and Operation; Capacities => [ Transmission Capacities ] 086A (R-Tronic) or Manual Shift Transmission.
• Make sure alignment bushings are properly installed during installation.
Sealant
• Thoroughly clean housing joint surfaces before applying sealing compounds.
• Apply Sealing Paste (AMV 188 001 02) evenly and not too thick.
• Do not allow sealing compound to enter ventilation openings.
Seals, O-rings, shaft seals
• Replace seals, O-rings, shaft seals
• After removing seals, check sealing surfaces on housing or shaft for burrs resulting from removal or damage.
• Replace seals, completely remove old seal and clean sealing surfaces.
• Coat O-rings with gear oil before inserting to prevent crushing rings during installation.
• Lightly oil the outer circumference of the radial shaft seals and fill the space between the sealing lips - arrow - halfway with sealing grease.
• The open side of the shaft seals point toward the fluid to be sealed in.
• Observe rules for cleanliness. Refer to => [ Clean Working Conditions ] Clean Working Conditions.
• After installing, check the transmission oil level and fill. Refer to => [ Oil Drain, Oil Fill and Oil Check Plug Assembly Overview ] Description and Operation. With R tronic transmission, also check the R tronic hydraulic unit oil level and fill. Refer to => [ Oil Level in R Tronic Hydraulic Unit, Adjusting ] Oil Level In R Tronic Hydraulic Unit, Adjusting.
Fasteners
• Do not strain circlips (replace if necessary).
• Circlips must locate properly in the groove.
• Replace spring pins. Installation position: Slit - A - should be in line with the line of force- arrow -.
Bolts and Nuts
• Loosen bolts in reverse order of tightening.
• Tighten and loosen bolts or nuts for securing covers and housings without tightening sequence in diagonal sequence in stages.
• Replace self-locking nuts.
• Clean threads of bolts that were applied with locking fluid using a wire brush. Then insert the bolts with locking compound; Locking compound.
• The tightening specifications stated apply to non-oiled nuts and bolts.
• Tightening torque with additional torque: After tightening to torque, these bolts must be tightened further to the specified angle, e.g. 40 Nm + 90° (90° corresponds to a quarter turn).
Adjusting Shims
• Use a micrometer to measure the shims at several points. Tolerance variations make it possible to find the exact shim thickness required.
• Check for burrs and damage.
• Do not install shims which are damaged or not in perfect condition.
Mount
• Set needle bearings, ball sleeves and roller sleeves with the inscribed side (greater thickness) facing toward drift.
• Install new tapered roller bearing as supplied and do not use additional oil.
• Install various bearings (removed tapered roller bearings) into transmission, lubricated with gear oil.
• Heat inner races of tapered roller bearings to approximately 100 °C with the Inductive Heat Unit (VAS 6414) before installing. Press on to the stop when installing, so there is no axial clearance.
• Warm inner race for needle and roller bearings to 130 °C max.
• Do not interchange inner and outer bearing races with those from other bearings of the same size, bearings are paired.
• Tapered roller bearings installed on a shaft must be replaced as a set and use same make of bearings.
Gears, Synchronizer Hubs, Selector Gear Inner Races
• To install, heat gear wheel inner race to approximately 100 °C with Inductive Heat Unit (VAS 6414).
• Heat the gear wheels and synchronizer hubs to approximately 100 °C with the Inductive Heat Unit (VAS 6414) before installing. Press on to the stop when installing, so there is no axial clearance.
• Observe installation position.
Selector Gears
• After assembly, check selector gears of 1st through 6th gear for axial play of 0.15 to 0.50 mm and ease of movement.
Synchronizer Rings
• Do not interchange. When reusing synchronizer rings, always install to the same gear wheel.
• Check for wear and replace if necessary.
• Coat with gear oil before installing.
Check the Synchronizer Rings
• Check coated friction surfaces - arrows 2 - from intermediate ring - B - for damage (flat areas, disintegrating areas or friction surface).
• Check the inner friction surface - arrow 1 - of the synchronizer ring - A - and the surfaces of the intermediate ring for grooves or scoring.
• On intermediate races - C - with coated friction surfaces - arrow 3 -, check coating for damage (disintegrating friction surface).
Damage on the selector gears and locking collars
• Damage to the synchronizer ring or gear wheel:
A Worn clutch spline on the synchronizer ring or gear wheel, tips worn off
• In comparison: synchronizer ring or gear wheel not damaged:
B Undamaged clutch spline on the synchronizer ring or gear wheel
• Picture of damage on the locking collar:
C Worn longitudinal inner spline camber on the locking collar, tips no longer there
• In comparison: locking collar undamaged
D Undamaged longitudinal inner spline camber on the locking collar