Rear Suspension - Awd Audi A6 C4

DESCRIPTION

Rear suspension consists of a crossmember, lower trapezoidal arm, transverse links, wheel bearing housing, strut assemblies and stabilizer bar with end links. (Scheme 14)

Scheme 14

WHEEL ALIGNMENT SPECIFICATIONS & PROCEDURES

Note. See SPECIFICATIONS & PROCEDURES article in WHEEL ALIGNMENT.

REMOVAL & INSTALLATION

AXLE SHAFT

Note. See AXLE SHAFTS - RWD article in DRIVE AXLES section for axle shaft removal, installation and overhaul.

CROSSMEMBER

Note. Each crossmember has different variations. Identification of variations is not available from manufacturer.

There are 3 rear crossmembers. (Scheme 15) Remove components as necessary to access and remove crossmembers. When installing, ensure crossmembers are centered. Align vehicle after service.

Scheme 15

Disconnect link rods from each end of stabilizer bar. Remove stabilizer bar clamp bolts and clamps from crossmember. Remove stabilizer bar. To install, reverse removal procedure. Use NEW self-locking nuts. Tighten fasteners to specification. See TORQUE SPECIFICATIONS .

Raise and support vehicle. Remove wheel. Remove transverse link from wheel bearing housing. Remove nut and install Tool (VW267A). Using tool, remove transverse link from crossmember. To install, bolt in transverse link. Tighten fasteners to specification. See TORQUE SPECIFICATIONS .

TRAPEZOIDAL ARM

Note. Check wheel alignment after servicing.

Removal

Raise and support vehicle. Remove wheel. Remove ABS sensor wiring. Disconnect brake pressure regulator spring. Loosen trapezoidal arm-to-wheel bearing housing bolt. (Scheme 16) Loosen trapezoidal arm-to-pivot mount bolt. Loosen trapezoidal arm-to-crossmember bolt. Remove support nuts from body studs. Remove support from trapezoidal arm. Remove remaining loosened bolts and trapezoidal arm.

Scheme 16

Installation

Reverse removal procedure. Use NEW nuts and bolts. Tighten all trapezoidal arm nuts and bolts with vehicle on the ground. Tighten fasteners to specification. See TORQUE SPECIFICATIONS . Check wheel alignment.

TRAPEZOIDAL ARM - FRONT SUPPORT BUSHING

Note. On vehicles built before VIN.....N000 001, support bushing is not replacable. Entire support must be replaced. When installing bushing halves, press only until bushing sleeve contacts support.

Remove trapezoidal arm support bushing from vehicle. Install Puller (Kukko 21/2 or equivalent) in bushing with claws between bushing halves. (Scheme 17) Tighten nut forcefully. Install 3.1" (80 mm) long 14 mm bolt in bushing. Using press and tools, press out front bushing half. (Scheme 18) If front bushing half breaks, use press and/or hacksaw to remove remaining front bushing half from support. Using press and tools, press out rear bushing half. (Scheme 18) Press in rear bushing half. (Scheme 19) Press in front bushing half in two steps. First step installs front bushing half approximately.20" (5 mm). (Scheme 20) Second step presses front bushing in completely.

Scheme 17

Scheme 18

Scheme 19

Scheme 20

Remove drive axle bolt. Raise and support vehicle. Remove wheel. Remove and support brake caliper. Remove brake rotor. Remove trapezoidal arm-to-wheel bearing housing bolt. Remove ABS sensor from wheel bearing housing. Remove wheel bearing housing-to-support bolt. Remove strut assembly lower bolt. Remove stabilizer bar link bracket. Remove outer transverse link bolt. Remove wheel bearing housing. To install, reverse removal procedure. Always use NEW self-locking nuts, transverse link bolt, trapezoidal arm bolts and axle bolt. Perform final tightening of trapezoidal arm, strut assembly and axle bolts with vehicle weight on wheels. Tighten fasteners to specification. See TORQUE SPECIFICATIONS . Check wheel alignment after servicing.

Front Bushing

Remove wheel bearing housing. Using press and tools, remove and install front bushing. (Scheme 21)

Scheme 21

Wheel Bearing

Remove wheel bearing housing. Remove wheel hub. See WHEEL HUB. (Scheme 22) Remove circlips. Using press, remove and install wheel bearing. (Scheme 23) Larger inner diameter of bearing faces wheel hub. Install circlips with gaps pointing down.

Scheme 22

Scheme 23

Wheel Hub

Remove wheel bearing housing. Using press and tools, remove and install wheel hub. (Scheme 24)

Scheme 24

Raise and support vehicle. Remove upper strut assembly nuts and bolts. Remove strut-to-trapezoidal arm bolt. Remove strut assembly. (Scheme 25)or (Scheme 26).

Scheme 25

Scheme 26

Disassembly

Put strut assembly in Tool (1752/2). Using spring compressor, compress strut spring until upper spring mount is free. (Scheme 27) On A6, remove upper nut using Tool 3017A. On S6, remove upper nut using Tool 3077 and hex wrench. On all vehicles, remove mounting bracket and damper ring. Remove spring compressor and spring. Remove remaining components. Using plastic-faced hammer, remove lower spring seat from shock absorber.

Scheme 27

Reassembly (A6)

To install, reverse disassembly procedure. Install lower spring seat with spring stop aligned with lower mounting eye. Ensure spring ends are against rubber stops. Use NEW shock rod nut. Tighten fasteners to specification. See TORQUE SPECIFICATIONS . Remove spring compressor. Remove strut assembly from tool.

Reassembly (S6)

Clamp strut in tool. Install lower spring seat with spring stop aligned with lower mounting eye. Install compressed spring on strut, aligning marked lower spring end with spring stop on strut. Install damper ring on top of spring, with end of spring against damper ring stop. Align mark on upper rubber mounting with proper mark on upper spring seat. (Scheme 28) Mark aligns with "R" for right side strut, "L" for left side strut. Align strut adapter on rubber mounting. (Scheme 29) Install strut adapter on Tool (1752/2). (Scheme 30) Turn upper spring plate until pointer indicates 4-8 degrees. (Scheme 31) Tighten clamping lever on tool. (Scheme 27) Use NEW shock rod nut. Tighten nut to specification. See TORQUE SPECIFICATIONS. Remove spring compressor. Remove strut assembly from tool.

Scheme 28

Scheme 29

Scheme 30

Scheme 31

To install, reverse removal procedure. Use NEW strut-to-trapezoidal arm bolt and nut. Tighten all trapezoidal arm nuts and bolts with vehicle on the ground. Tighten fasteners to specification. See TORQUE SPECIFICATIONS .

TORQUE SPECIFICATIONS

Note. Always use NEW outer axle bolt, trapezoidal arm support-to-wheel bearing housing bolt, trapezoidal arm-to-wheel bearing housing bolt, trapezoidal arm-to-front support bolt, driveshaft bolts, brake caliper bolts and all self-locking nuts. Replace any worn or corroded fasteners.

TORQUE SPECIFICATIONS

See also:
• TORQUE SPECIFICATIONS
• WHEEL HUB