Attach the hydraulic control unit -1- 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 -2 through 5- hand-tight. One bolt -2- has a permanent seal on the head. Coat the thread with Sealing CompoundD 176 501 A1.

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

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

-- Install the All Wheel Drive Pump -V415-. Refer to All Wheel Drive Pump -V415-, 0BE, 0BF .

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

Fig 1: Identifying Rear Final Drive Wiring Harness Bracket

Courtesy of AUDI OF AMERICA, LLC

-- Connect the connectors -4 and 2-. Pay attention to the marks made during the removal, that identify which connector goes 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.

NOTE:

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

Fig 2: Identifying Oil Pressure/Temperature Sensor Connectors

Courtesy of AUDI OF AMERICA, LLC

-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, CHECKING LEVEL, 0BE, 0BF .

-- Fill the ATF in the rear final drive and check the ATF level. Refer to ATF LEVEL, CHECKING, 0BE, 0BF .

-- Install the rear section of the exhaust system and align it so it is free of tension. Refer to ENGINES CPNA - EXHAUST SYSTEM, INSTALLING WITHOUT TENSION , ENGINES CTUB - EXHAUST SYSTEM, INSTALLING WITHOUT TENSION , ENGINES CEUA, CGTA, CTFA & CTGA - EXHAUST SYSTEM, INSTALLING WITHOUT TENSION , ENGINES CDRA - EXHAUST SYSTEM, INSTALLING WITHOUT TENSION or ENGINES CEJA & CTNA - EXHAUST SYSTEM, INSTALLING WITHOUT TENSION .