Audi Workshop Service and Repair Manuals

Re-determining thickness of shim “S4”

This adjustment is necessary when the following components are renewed:

t	Intermediate housing → Anchor

t	Hollow shaft → Anchor

t	Tapered roller bearing of pinion shaft/hollow shaft → Anchor

This adjustment restores the required preload of the tapered roller bearings for the pinion shaft and hollow shaft.

1 -

Shim “S4”

2 -	Intermediate housing

q	If renewing, re-determine shim “S4”

3 -	Gearbox housing

4 -	Hollow shaft

q	If renewing, re-determine shim “S4”

5 -	Tapered roller bearing of pinion shaft/hollow shaft

q	Arrangement and components → Anchor

q	If renewing, re-determine shim “S4”

6 -	Pinion shaft

a -	Intermediate housing depth

b -	Dimension from pinion gear to contact shoulder of tapered roller bearing on hollow shaft

q	Tapered roller bearing (pinion shaft/hollow shaft) preloaded to 10 Nm → Anchor

S4 -	Thickness of shim “S4”

Refer to table of adjustments → Anchor when renewing the pinion shaft (final drive set).

Special tools and workshop equipment required

t  End measuring plate -VW 385/32- from universal measuring tool -VW 385-

t  Clamping sleeve -3116- t  Digital depth gauge -VAS 6087-

Determining shim when renewing intermediate housing –  Measure depth -a- on old and new intermediate housing.

Example:
Depth -a- (old intermediate housing)	124.40 mm
Depth -a- (new intermediate housing)	124.65 mm
Difference	= 0.25 mm

l  If the new intermediate housing is deeper, install a thicker “S4” shim. l  If the old intermediate housing is deeper, install a thinner “S4” shim.

Example:
Previous “S4” shim	0.95 mm
Difference	+ 0.25 mm
New “S4” shim	= 1.20 mm

For available shims refer to table → Anchor.

Determining shim when renewing hollow shaft –  Install tapered roller bearing components -1 ... 4- for pinion shaft/hollow shaft with grease -G 052 128 A1-. Arrangement: 1 -  Flange ring - tapered contact surface to tapered rollers 2 -  Tapered rollers (Qty. 23) - with larger diameter facing towards pinion shaft head 3 -  Support ring - tapered contact surface to tapered rollers 4 -  Corrugated spring 5 -  Circlip for tapered roller bearing for pinion shaft

l  Tapered roller bearing for pinion shaft/hollow shaft -A- and corrugated spring -B- installed. –  Fit needle bearing -C- and lubricate thoroughly with oil. –  Insert pinion shaft in hollow shaft -D-.

–  Tighten clamping sleeve to exactly 10 Nm. A -  Jaw protectors

–  Fit end measuring plate -VW 385/32- onto pinion gear and measure dimension -d-. l  Use a digital depth gauge -VAS 6087-. l  Top measuring point is shoulder for inner race of small tapered roller bearing. –  Fit new hollow shaft and measure dimension -d- again.

Example:
Dimension -d-, old hollow shaft	248.50 mm
Dimension -d-, new hollow shaft	248.70 mm
Difference	= 0.20 mm

l  Install a correspondingly thinner shim “S4” if dimension -d- of new hollow shaft is greater. l  Install a correspondingly thicker shim “S4” if dimension -d- of new hollow shaft is less. –  Select thickness of required shim(s) from following table:

Available shims - Thickness of shims in mm 1)2)
0.45	0.65	0.85
0.50	0.70	0.90
0.55	0.75
0.60	0.80
l  1) For Part Nos. refer to → Electronic parts catalogue. l  2) Different shim thicknesses make it possible to obtain the exact shim thickness required, if necessary, fit 2 shims.