Components
Components
The maximum possible care, cleanliness and proper tools are essential to ensure satisfactory and successful transmission repairs. The usual basic safety precautions also apply when carrying out vehicle repairs.
A number of generally applicable instructions for individual repair procedures, which are otherwise mentioned at various points in the Repair Information, are summarized here. They apply to this Repair Information.
Special tools and workshop equipment
For a complete list of special tools used in this repair information: see " Special tools and equipment" or "Special tools".
Transmission
• Rules of cleanliness for working on automatic transmissions. Refer to => [ Clean Working Conditions ] Clean Working Conditions.
• Do not run engine with the oil pan removed or without ATF filling and do not tow vehicle.
• Clean ATF lines and ATF cooler when replacing automatic transmission. Refer to => [ ATF Lines and Cooler, Cleaning ] 01VA Transmission.
• Secure torque converter on removed transmission to keep it from falling out.
• Thoroughly clean all connections and the surrounding area before disconnecting.
• Check installation dimension of torque converter before installing transmission. Refer to => [ Torque Converter, Installing ] 01VA Transmission
• When installing transmission, make sure centering sleeves are correctly seated in engine.
• Place parts that have been removed on a clean surface and cover. Use foils and paper. Use lint-free cloths only!
• Carefully cover over opened components or seal, if repairs are not carried out immediately.
• Only install clean components: Only unpack replacement parts immediately prior to installation.
• Check, and if necessary correct amount of the following fluids when replacing the automatic transmission. ATF in planetary gear. Refer to => [ ATF Level, Checking ] [1][2]ATF Level, Checking, gear oil in front final drive => [ Front Final Drive Gear Oil, Checking ] [1][2]Front Final Drive Gear Oil, Checking, gear oil in center differential => [ Center Differential Gear Oil, Checking and Filling ] Center Differential Gear Oil, Checking and Filling. Capacities and specifications => [ Capacities ] 01VA Transmission onward.
• When replacing the rear final drive, check and if necessary, correct oil level in rear final drive. Capacities and specifications. Refer to => [ Capacities ] 01VA Transmission => Transmission and Drivetrain Transmission and Drivetrain
O-rings, gaskets, seals
• Always replace O-rings, gaskets and sealing rings.
• After removing gaskets and seals, always inspect the contact surfaces at housing or shaft for burrs resulting from removal or for other signs of damage.
• Thoroughly clean housing sealing surfaces before assembling.
• Lightly lubricate O-rings before installing, this prevents the rings from being pinched when inserting.
• Before installing, fill gap between sealing lips (arrow) of radial-shaft seals half way with sealing grease 052 128 A1.
• The open side of the seals face toward the fluid to be sealed in.
• For installation, lightly coat outer circumference and sealing lip with ATF or transmission oil, depending on the installation location.
• Use only ATF in areas near ATF. Other lubricating substances cause functional problems in the hydraulic transmission control.
• When pressing in new seals, make sure the sealing lip does not run on the same point as the sealing lip of the old seal (use insertion depth tolerances).
• After installing, check and if necessary correct fluid levels in the affected area. Refer to ATF in planetary gear => [ ATF Level, Checking ] [1][2]ATF Level, Checking, gear oil in front final drive => [ Front Final Drive Gear Oil, Checking ] [1][2]Front Final Drive Gear Oil, Checking, gear oil in center differential => [ Center Differential Gear Oil, Checking and Filling ] Center Differential Gear Oil, Checking and Filling, gear oil in rear final drive => Transmission and Drivetrain Transmission and Drivetrain
Capacities and specifications. Refer to => [ Capacities ] 01VA Transmission onward.
Nuts, bolts
• Loosen bolts in reverse order of tightening sequence.
• Tighten and loosen bolts or nuts for securing covers and housings without tightening sequence in diagonal sequence in stages.
• Do not cant, and loosen and tighten especially sensitive parts - e.g. valve body - in diagonal manner in stages.
• The tightening torques stated apply to non-oiled nuts and bolts.
• Always replace self-locking nuts and bolts.
• Using a wire brush, clean threads of bolts which are secured with locking compound. Next, insert bolts using AMV 185 101 A1.
• Threaded bores into which self-locking bolts or bolts with locking compound are threaded in, must be cleaned (e.g. using threaded tap). Otherwise there is danger that the bolts may shear when removed again.
Circlips
• Do not over-stretch circlips.
• Always replace damaged or over-stretched circlips.
• Circlips must be fully seated in groove.
Mount
• Install needle bearings with the lettering on the bearing (the side with thicker metal) facing the drift.
• Insert bearing with transmission oil or ATF, depending on installation location.
Valve body
• Replace transmission if shift members are burnt.
• The valve body is allocated to the transmission code letters.
Guided Troubleshooting, Vehicle On Board Diagnostic (OBD) and Test Instruments
• Before performing repairs on the automatic transmission, the malfunction cause must be determined as exact as possible via the tester (VAS5051) in the operating modes ""Guided Fault Finding", "Vehicle Self-Diagnosis" and "Test Instruments."
