Attach the hydraulic control unit to the rear final drive as follows:

First install the lines -6- and -7- into the chambers hand-tight -arrows B-.

Then install the bolts -3 to 5- hand-tight.

Coat the threads of the bolt -2- with Sealing Compound:D 176 501 A1  .

Install the bolt -2- with a seal.

Tighten the M8 x 30 screws -2 through 5- to the tightening specification in the sequence: -4-, -2-, -5- and -3-.

Tighten the nuts -A arrows- and -B arrows- on the left -6- and right -7- lines to the tightening specification.

-- Install the All-Wheel Drive Pump -V415-. Refer to Installing .

Fig 1: Identifying Rear Final Drive Wiring Harness Bracket

Courtesy of AUDI

-- Install the wiring harness -3- to the final drive and subframe -items 5 through 7-.

-- Connect the connectors -4- and -2-. Pay attention to the marks made during the removal, that identify the allocation to the Oil Pressure/Temperature Sensor -- and which connectors go to the Clutch Valves --.

-- If equipped, position the wiring harness bracket -1- on the rear final drive and tighten the bolts -arrows- to the tightening specification. Make sure the wiring harness -3- does not get pinched.

Allocation of the connectors for the Oil Pressure/Temperature Sensor -- and Clutch Valves -- :

Fig 2: Identifying Oil Pressure/Temperature Sensor Connectors

Courtesy of AUDI

• -1- = Oil Pressure/Temperature Sensor 2 -G640- Connector
• -2- = Oil Pressure/Temperature Sensor -G437- Connector
• -3- = All-Wheel Drive Clutch Valve 2 -N446- Connector
• -4- = All-Wheel Drive Clutch Valve -N445- Connector

-- Fill the rear final drive with gear oil and then check the level. Refer to GEAR OIL LEVEL, CHECKING, 0D3 "quattro sport" AND 0BX "quattro sport" .

-- Fill the ATF in the rear final drive and check the ATF level. Refer to ATF LEVEL, CHECKING .

-- Install the rear section of the exhaust system and align it so it is free of tension. Refer to OVERVIEW - MUFFLER - 3.0L , OVERVIEW - MUFFLER - Servicing 3.0L .