1997 AUDI A4 01A Transmission Final Drive Gear Set Workshop Manual

1) Must have run at least 50 km (30 miles)
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39-161

Checking measurements

Checking dimension "r"

- Turn pinion shaft at least 5 turns in both
directions.

If the shims have been correctly selected, the dial indicator should now
display the value of "r" as marked on the ring gear, reading
counterclockwise (red scale), within a tolerance of 0.04 mm. - Insert universal mandrel and carry out check measurement.

- Secure pinion shaft nut using mandrel.
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39-162

Ring gear, adjusting


Adjusting differential
The ring gear must be adjusted if any of the
components have been replaced table,
Page 39
-149
.

Notes:

Differential tapered roller bearings are low
friction bearings. Therefore the friction torque
only has a limited use as a check. Correct
adjustment is only possible by determining the
total shim thickness Stotal.
Do not additionally oil new tapered roller
bearings for the friction torque measurement.
The bearings have already been treated with a
special oil by the manufacturer.

Determining total shim thickness "Stotal" for
shims S1 + S2
(Setting preload of tapered roller bearing for
differential)
Pinion shaft removed or ring gear removed
from differential housing.

- Pry out drive flange seal using pry bar.
Pa
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- Remove differential tapered roller bearing outer
races and remove shims Page 39
-121
.
Pa
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39-163

- Press left tapered roller bearing outer race for
differential (housing side) with shim S2 into
housing Page 39
-126, Fig. 2
. To perform the
measurement use shim S2* with thickness of
1.00 mm (one 0.80 mm shim and one 0.20 mm
shim).

Note:
For measurement specification, a shim S2 of 1.0
mm thickness is initially inserted which will be
designated S2* in the following. After determining
the backlash S2* will be replaced by the correct
shim S2.

- Press in right tapered roller bearing outer race
for differential (final drive cover side) without
shims, until stop Fig. 8, Page 39
-130
.

- Insert differential into housing. Ring gear is
positioned on right side (cover side).

- Install final drive cover and tighten bolts to 25
Nm (18 ft lb).

- Install special tools VW521/4 locking sleeve and 521/8 bushing on
housing side into differential housing.
- Turn final drive housing so final drive cover faces upward.
Pa
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39-164

- Turn differential 5 turns in both directions to
settle tapered roller bearing.

- Place VW385/17 magnetic plate onto
differential.

- Install measuring tools.
A - Dial indicator extension approx. 30 mm long
B - Hex-head bolt M8 x 45
- Place dial indicator extension on center of VW385/17 magnetic plate.
- Set dial indicator (3 mm measuring range) to "0" with 2 mm preload.

Note:
If the measurement has to be repeated, the differential must again be
turned 5 turns in each direction to settle the tapered roller bearing. - Lift up differential without turning; read off play on dial indicator and
note.
Measurement in following example: 0.50 mm
Pa
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gear set, recommended se
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39-165

Formula:
Stotal
=
S2* + measurement + bearing
preload

Example:

Inserted shim(s) S2* 1.00
mm
+ Measured value 0.50
mm
+ Bearing preload (constant) 0.30
mm
= Total shim thickness Stotal for shims
S1 + S2
1.80
mm
Pa
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39-166

Determining thickness of shim "S1*"

Notes:

The preliminary shim S1* will be replaced with
the final shim S1 after determining the
backlash.
The total shim thickness Stotal remains
unchanged.

Formula:
S1* = Stotal - S2*

Example:


Total shim thickness Stotal for shims
S1 + S2
1.80
mm
- Inserted shim(s) S2* 1.00
mm
= Thickness of shim S1* 0.80
mm

- Determine shim(s) according to table Page 39
-171
.
Pa
ge 24 of 31 Final drive
gear set, recommended se
quence for ad
justin
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yp
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pair&id=AUDI.B5.TM02.39.18