Specifications & Procedures Audi A6 C5

VEHICLE IDENTIFICATION

For models covered in this article, see MODEL IDENTIFICATION table.

MODEL IDENTIFICATION

IDENTIFYING SUSPENSION VARIATIONS

Various suspensions are offered as options. These variations are identified by part numbers. Running gear version installed in vehicle is indicated by the factory weight code on the vehicle data plate. (Scheme 1) Vehicle data plate is located in spare tire well and in service book. The following table identifies suspension versions. Identifying proper suspension version is critical for wheel alignment. See IDENTIFYING SUSPENSION VARIATIONS table.

IDENTIFYING SUSPENSION VARIATIONS

Scheme 1

A6 & S6

The vehicle must only be lifted at the specified points in order to prevent damaging the floor of the vehicle and to prevent the vehicle from tipping. The vehicle should NEVER be lifted by the oil pan, the transmission or the front or the rear subframes. Otherwise major damage can result. Make sure there is sufficient clearance between lowest parts of vehicle and vehicle lift before driving onto lift.

Lift front of vehicle at the longitudinal reinforcement of the floor pan at the area of the marking for the vehicle jack. (Scheme 2)

Scheme 2

Lift rear of vehicle at the vertical reinforcement of the lower sill in the area of the marking for the vehicle jack. (Scheme 3)

Scheme 3

Allroad

The vehicle should never be lifted or jacked up from underneath the engine oil pan, transmission housing, front or rear axle or the body side members. This could lead to serious damage. The same lifting points for the lift also apply when a floor jack is used. To avoid damage to the underbody or chassis frame, it is necessary to insert a rubber pad between the shop jack and the lift points.

Lift front of vehicle at the longitudinal reinforcement of the floor pan at the area of the marking for the vehicle jack. (Scheme 2)

Lift rear of vehicle at the vertical reinforcement of the lower sill in the area of the marking for the vehicle jack. (Scheme 3)

Scheme 4

1. Before lifting the vehicle with a jack or lift, press buttons 1 and 3 at the same time for at least 5 seconds with the ignition switched on. (Scheme 4)
2. When the system is in "jack mode", the LEDs on control buttons 1 and 3, the yellow LED for the manual mode on the level indicator 2 and warning light for level control in the instrument cluster will all come on. Once this happens, switch off the ignition. The vehicle can now be lifted.
3. To deactivate the "jack mode", press buttons 1 and 3 at the same time for at least 5 seconds. Warning light in the instrument cluster, the LED for manual mode and the LEDs on the control buttons will all turn off. The original system state and full functionality of the ride height system are now restored. In addition, the "jack mode" will automatically be deactivated when vehicle speed exceeds 3 MPH (5 km/h).

PRELIMINARY CHECKS

Before beginning wheel alignment procedures, ensure following are checked.

1. All wheels and tires are of approved size (all 4 identical) and tires are properly inflated. Tread depth has no more than .08" (2 mm) difference between tires on same axle. Correct as necessary.
2. Check suspension and suspension components for looseness or damage. Correct as necessary.
3. Check wheel bearing play and condition. Correct as necessary.
4. Fuel tank full. Spare tire and tools stored in appropriate storage area. Windshield washer reservoir full. Correct as necessary.
5. On vehicle equipped with level control (1BG suspension), turn ignition on and allow height control process to run until completed.
6. Ensure alignment equipment sliding plates and turn tables are not touching the end stop when checking wheel alignment.
7. Alignment is to always include both front and rear axles.
8. Check wheels for excessive runout or out-of-balance condition. Balance or repair wheels as necessary. Permissible lateral runout of the wheel rims can already exceed the specified toe-in setting tolerance. If compensation for wheel run-out is not performed, it will not be possible to obtain a correct toe-in adjustment.
9. For vehicles with 4-wheel air suspension (1BY), vehicle must be at normal level. Deactivate level control system. See «DEACTIVATING/ACTIVATING JACK MODE FOR RIDE HEIGHT SYSTEM (ALLROAD)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures) . Be sure there is sufficient pressure in pressure reservoir. Check height between center of wheel and bottom edge of fender. Specification is 15.8" +/- .197" (402 mm +/- 5 mm). If this is not the case, basic setting must be performed.

Note. Basic setting of 4-wheel air suspension (1BY) requires using Audi factory scan tool (VAS 5051 or VAS 5052), or equivalent aftermarket scan tool.

Note. On the Allroad, it may be necessary to move the turn tables after raising the vehicle, to reach free-play for the pick-up sensors.

Note. While limited information is available, vehicle manufacturer does not support alignment information using aftermarket alignment equipment. To properly align vehicle, it is recommended to use VAG 1813 alignment computer. All procedures in this article are written using VAG 1813 alignment computer.

Vehicles That Have Been In An Accident

On vehicles which have been in accidents, before checking or adjusting toe or toe constant "S", steering rack must be in midway position.

Place steering rack in midway position as instructed by wheel alignment computer. On steering gear, remove sealing bolt and install Centering Bolt (VAG1907). (Scheme 5) See SPECIAL TOOLS. It may be necessary to have an assistant move steering wheel until centering hole in rack is felt.

With rack locked in place, check whether steering wheel is mounted as horizontal as possible on steering column when wheels are in straight-ahead position. Reposition steering wheel, if necessary. Otherwise centering of toothed shaft cannot be guaranteed. See appropriate AIR BAG RESTRAINT SYSTEM article in RESTRAINTS.

After toe-in is set, remove centering pin. Reinstall sealing bolt and torque to 16 ft. lbs. (22 N.m).

Note. If steering wheel position was changed, and vehicle is equipped with Electronic Stabilization Program (ESP), zeroing of steering angle sensor must be performed using scan tool. For zero position of steering angle sensor procedure, see appropriate ANTI-LOCK article in BRAKES.

Scheme 5

WHEEL ALIGNMENT WORK SEQUENCE

When performing wheel alignment procedures, observe following work sequence

1. Check camber at rear axle. Adjust as necessary.
2. Check rear axle toe. Adjust as necessary.
3. Check front axle camber and even out if necessary.
4. If top rear transverse control arm, mounting bracket, wheel bearing housing, tie rod, rack and pinon steering box or carrier (subframe) were changed, check behavior of the toe constant "S" on front axle (toe-in curve).
5. Check front axle toe with vehicle in initial position. Adjust as necessary.
6. If suspension adjustments were changed, and vehicle is equipped with Electronic Stability Program (ESP), zeroing of steering angle sensor must be performed using scan tool. For zero position of steering angle sensor procedure, see appropriate ANTI-LOCK article in BRAKES.

CASTER ADJUSTMENT (FRONT OR REAR)

Front and rear caster are not adjustable. If caster is not as specified, locate and replace damaged or worn suspension parts. Before measuring caster values, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE

Front Wheel Drive

Before attempting any adjustments, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE . Camber is not adjustable. If camber is not as specified, check axle beam for damage and replace components as necessary.

All Wheel Drive

Before attempting any adjustments, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE .

Loosen eccentric retaining nut located on the lower rear control arm. (Scheme 6) Set camber by turning eccentric nut until specified camber value is met. See WHEEL ALIGNMENT SPECIFICATIONS. Maximum adjustment range is 90 degrees to left or right of center position. Tighten eccentric nut to 74 ft. lbs. (100 N.m). Recheck rear camber.

Scheme 6

Rear Toe Adjustment (FWD)

Before attempting toe adjustment, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE .

While rear axle toe is not adjustable on FWD models, toe can be evened out. By moving the rear axle (in the elongated holes), it is possible to even out individual toe settings. Loosen mounting bolts at mounting brackets. Loosen brake pedal depressor. While observing rear toe display on alignment computer, even out individual toe settings by moving axle beam within elongated holes in mounting brackets. See WHEEL ALIGNMENT SPECIFICATIONS . Tighten axle beam bracket-to-body bolts (M12 x1.5) in 2 stages. Tighten to 81 ft. lbs. (110 N.m), then turn an additional 90 degrees.

Apply brake pedal depressor. If overall toe setting is outside permitted range, or if it is not possible to even out the individual settings, the axle beam must be checked for damage and replaced if necessary. It may also be necessary to check body alignment in the area of the rear axle mounting points and perform repairs as necessary.

Rear Toe Adjustment (AWD)

Before attempting toe adjustment, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE. Loosen toe eccentric nut. Adjust toe by turning eccentric bolt to specified value. See WHEEL ALIGNMENT SPECIFICATIONS. (Scheme 7) Tighten nut and recheck alignment angles after adjustments.

Scheme 7

CAMBER ADJUSTMENT (FRONT)

Before attempting any adjustments, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE .

Front wheel camber cannot be set separately. Camber can be evened out uniformly, by loosening subframe bolts and shifting subframe position until correct camber range is obtained.

Working under vehicle, remove sound-deadening pan. LOOSEN, but do not remove, subframe bolts No. 1-8. (Scheme 8) While observing wheel alignment computer, use a plastic coated pry bar to press subframe from side to side until specified value is reached. (Scheme 9) See WHEEL ALIGNMENT SPECIFICATIONS.

Tighten subframe bolts in the following order

1. No. 7 and No. 8: 81 ft. lbs. (110 N.m), plus an additional 90° turn
2. No. 5 and No. 6: 81 ft. lbs. (110 N.m), plus an additional 90°
3. Nos. 1, 2, 3 and 4 to 44 ft. lbs. (60 N.m)

After subframe bolts are torqued, recheck camber range. Readjust as necessary.

Scheme 8

Scheme 9

TOE-IN CURVE ADJUSTMENT

Note. An incorrectly adjusted toe-in curve adjustment causes the vehicle to pull to one side when braking or accelerating or when driving over bumps. Toe-in curve adjustment can also be referred to as toe constant "S" adjustment.

When the front wheels compress or rebound, the wheel's toe changes as a function of the compression and rebound travel. The resulting values are called toe-in curve.

The wheel alignment computer determines the toe constant "S" from a value measured in initial position and a value measured in raised position. In the process it compares actual values with specified values and displays them on the screen. Toe-in curve is adjusted when vehicle is in a raised position, by vertical adjustment of the tie-rod end.

Different adapters are needed for lifting, depending on suspension variation. To identify application of suspension and adapter (Scheme 10) To identify adapter, see SPECIAL TOOLS. To prepare vehicle for checking toe-in curve adjustment, place vehicle in initial position by performing appropriate procedure.

Scheme 10

Note. Before measuring toe-in constant, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE .

Bringing Vehicle Into Initial Position For Alignment (Suspension Variations 1BA, 1BC, 1BE, 1BG, 1BH, 1BP, 1BT and 1BJ)

Due to the different alignment platforms, it may be necessary to raise vehicle at front axle so that it is possible to insert Spacer (VAG1925). After vehicle is lowered, it should be bottomed out. To place vehicle in initial position for alignment perform following

1. Install Spacer (VAG1925) with the adapters (VAG1925/3 or VAG1925/4). See «SPECIAL TOOLS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures).
2. Unscrew both thread spindles until they just come to rest against front bolts of carrier. (Scheme 11) This MUST NOT raise vehicle. Vehicle must be standing on its wheels. Vehicle is now in initial position. On vehicles with a level control system, turn ignition on and wait until vehicle height has settled. If vehicle is equipped with sport suspension (1BE), go to next step. If not, go to step 4.
3. For vehicles with sport suspension (1BE), lift front of vehicle at front lifting point. Place Adapter (VAG 1925/6) on Spacer Adapter (VAG 1925/3 or 1925/4). (Scheme 13)Lower vehicle onto adapter. Vehicle is now in initial position. Go to next step.
4. On all except sport suspensions, this is the position in which alignment program checks whether existing toe-in per wheel corresponds to specified value of +10' +/-30' (rough pre-adjustment). If toe is not as specified, adjust toe-in to specification. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front).
5. Place lifting jacks under front end jacking points and lift vehicle 2.4" (60 mm). With vehicle lifted as specified, push cylinder from threaded spindles and fix with safety bolts. (Scheme 12) Ensure that safety bolts are correctly positioned. Lower vehicle onto distance caliper. Observe and compare toe-in constant "S" measurement on alignment computer to specifications. See «WHEEL ALIGNMENT SPECIFICATIONS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__wheel-alignment-specifications).
6. If toe-in constant "S" measurement is as specified, check toe-in. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front). If toe-in constant "S" measurement is not as specified, adjust as necessary. See «ADJUSTING TOE-IN CURVE (ALL MODELS)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__adjusting-toe-in-curve-all-models).

Scheme 11

Scheme 12

Scheme 13

Bringing Vehicle Into Initial Position For Alignment (Suspension Variations 1BB)

Due to the different alignment platforms, it may be necessary to raise vehicle at front axle so that it is possible to insert VAG1925 spacer. After vehicle is lowered, it should be bottomed out.

1. Insert Spacer (VAG 1925) using Spacer Adapters (VAG 1925/3 or 1925/4) and Adapter (VAG 1925/6). (Scheme 13)
2. Unscrew both threaded spindles until they just come to rest against front bolts of carrier. (Scheme 11) Vehicle MUST NOT be raised as a result of this. Vehicle is now in initial position.
3. At this point, alignment program checks whether existing toe-in per wheel corresponds to specified value of +10' +/-30' (rough pre-adjustment). If toe is not as specified, adjust toe-in to specification. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front)
4. Place lifting jacks under front end jacking points and lift vehicle 1.57" (40 mm). Remove Adapter (VAG1925/6). With vehicle lifted as specified, push cylinder from threaded spindles and fix with safety bolts. (Scheme 12) Ensure that safety bolts are correctly positioned. Lower vehicle onto Spacer (VAG 1925). Observe and compare toe-in constant "S" measurement on alignment computer to specifications. See «WHEEL ALIGNMENT SPECIFICATIONS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__wheel-alignment-specifications).
5. If toe-in constant "S" measurement is as specified, check toe-in. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front). If toe-in constant "S" measurement is not as specified, adjust as necessary. See «ADJUSTING TOE-IN CURVE (ALL MODELS)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__adjusting-toe-in-curve-all-models).

Bringing Vehicle Into Initial Position For Alignment (Suspension Variations 1BY)

Due to the different alignment platforms, it may be necessary to raise vehicle at front axle so that it is possible to insert VAG1925 spacer. After vehicle is lowered, it should be bottomed out.

1. Insert Spacer (VAG 1925) using Spacer Adapters (VAG 1925/3 or 1925/4) and Adapter (VAG 1925/6). (Scheme 13)
2. Unscrew both threaded spindles until they just come to rest against front bolts of carrier. (Scheme 11) Vehicle MUST NOT be raised as a result of this. Vehicle is now in initial position.
3. At this point, alignment program checks whether existing toe-in per wheel corresponds to specified value of +10' +/-30' (rough pre-adjustment). If toe is not as specified, adjust toe-in to specification. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front)
4. Place lifting jacks under front end jacking points and lift vehicle 2.4" (60 mm). With vehicle lifted as specified, push cylinder from threaded spindles and fix with safety bolts. (Scheme 12) Ensure that safety bolts are correctly positioned. Lower vehicle onto Spacer (VAG 1925). Observe and compare toe-in constant "S" measurement on alignment computer to specifications. See «WHEEL ALIGNMENT SPECIFICATIONS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__wheel-alignment-specifications).
5. If toe-in constant "S" measurement is as specified, check toe-in. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front). If toe-in constant "S" measurement is not as specified, adjust as necessary. See «ADJUSTING TOE-IN CURVE (ALL MODELS)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__adjusting-toe-in-curve-all-models).

Adjusting Toe-In Curve (All Models)

Note. For wheel bearing housings without a groove and tie rod ends with a ring, the upward adjustment travel is about 2 mm less. If the adjustment travel is not sufficient, then the ring on the tie rod end should be removed.

1. Before attempting toe-in curve adjustment, see «PRELIMINARY CHECKS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__preliminary-checks) and «WHEEL ALIGNMENT WORK SEQUENCE»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__wheel-alignment-work-sequence).
2. On tie rod end, loosen nut "A". (Scheme 14)and (Scheme 15).
3. Unscrew bolt "B" about.160" (4 mm). Press down on tie rod end until it stops.
4. Screw in adjustment bolt "B" until toe-in curve specified value is reached. See «WHEEL ALIGNMENT SPECIFICATIONS»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__wheel-alignment-specifications).
5. Tighten nut "A" to 37 ft. lbs. (50 N.m). Recheck toe-in curve.
6. Tighten NEW bolt "B" to 62 INCH lbs. (7 N.m). Lower vehicle to initial position.
7. Turn down threaded spindle. On all vehicles except those with a sport suspension, bounce vehicles with standard suspension several times. Allow suspension to settle.
8. On all vehicles, wheel alignment computer will check toe constant "S" value again. If values are as specified, set toe-in. See «TOE ADJUSTMENT (FRONT)»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures__toe-adjustment-front). If values are not as specified, repeat adjustment procedure.

Scheme 14

Scheme 15

TOE ADJUSTMENT (FRONT)

Before attempting toe adjustment, see PRELIMINARY CHECKS and WHEEL ALIGNMENT WORK SEQUENCE .

Loosen lock nut "B" on tie rod. (Scheme 16) Also, loosen rack boot outer clamp. Adjust toe by turning hex nut "A" until proper setting is reached. Do not allow boot to twist during adjustment, straighten twisted boots when toe in is set. Tighten tie rod lock nutto 30 ft. lbs. (40 N.m). Recheck toe adjustment.

Scheme 16

Scheme 17

WHEEL ALIGNMENT SPECIFICATIONS

FRONT AXLE WHEEL ALIGNMENT SPECIFICATIONS (ALL ENGINES - FWD ONLY)

Scheme 18

REAR AXLE WHEEL ALIGNMENT SPECIFICATIONS (ALL ENGINES - FWD ONLY)

FRONT AXLE WHEEL ALIGNMENT SPECIFICATIONS (AWD VEHICLES - V6 ENGINES)

REAR AXLE WHEEL ALIGNMENT SPECIFICATIONS (AWD VEHICLES - V6 ENGINES)

Scheme 19

FRONT AXLE WHEEL ALIGNMENT SPECIFICATIONS (AWD VECHICLES - 4.2L V8)

REAR AXLE WHEEL ALIGNMENT SPECIFICATIONS (AWD VECHICLES - 4.2L V8)

Scheme 20

WHEEL ALIGNMENT SPECIFICATIONS (ALLROAD- 1BY SUSPENSION)

Scheme 21

See also:
• MODEL IDENTIFICATION
• PRELIMINARY CHECKS
• WHEEL ALIGNMENT WORK SEQUENCE
• WHEEL ALIGNMENT SPECIFICATIONS
• TOE ADJUSTMENT (FRONT)
• ADJUSTING TOE-IN CURVE (ALL MODELS)