Defining total shim thickness "Stotal" of shims "S1" + "S2"

WARNING: This page is about a different car, the 2004 Audi A4, 2003 Audi A4, and 2002 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

(Adjusting pre-load of differential tapered roller bearing)

Pinion removed
If only differential tapered roller bearings are replaced, the ring gear can be removed from the differential housing. In this case, the pinion does not have to be removed.

Pull out oil seals for drive flanges using extractor lever VW 681.
Remove outer races of differential tapered roller bearings and take out shims. Refer to Differential, disassembling and assembling .

Fig 1: Pressing Outer Race/Tapered Roller Bearing Into Transmission Housing

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Drive outer race of small tapered roller bearing and shim "S2" into transmission housing. For measurement purposes, a shim "S2*" 1.20 mm thick is used (2 shims of 0.60 mm).

NOTE: A shim "S2" 1.20 mm thick is used provisionally as a reference value. It is referred to below as "S2*". Once torsional side clearance is determined, "S2*" is replaced by the definitive "S2".

Fig 2: Driving In Outer Race Of Tapered Roller Bearing Into Cover

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Press outer race of tapered roller bearing into cover of differential without shim "S1".
Insert differential without driving gear for sender of speedometer -G22 in transmission housing.
Install cover of differential using 4 bolts (25 Nm).
Position transmission so that cover of differential faces upward.

Rotate differential 5 turns in both directions, so that tapered roller bearing slips into place.
Lay measuring plate VW 385/17 on differential.

Fig 3: Installing Magnetic Plate 50Mm Dia. VW 385/17 And Dial Gauge

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Set up measuring tools using a 30 mm dial indicator extension.
Set dial indicator (3 mm measuring range) -A- to "0" with 2 mm pre-load.

NOTE: Measuring tip of dial indicator must be positioned on center of differential.

Lift differential without turning; read and note clearance indicated on dial indicator.

Measured value in following example: 0.62 mm

NOTE:

Fig 4: Securing Special Tools VW 521/4 And VW 521/12 At Right On Differential (Housing Side)

Courtesy of VOLKSWAGEN UNITED STATES, INC.

To raise differential, fasten special tools VW 521/4 and VW 521/12 to right of differential (housing side).
If the measurement is repeated, first rotate the pinion and hollow shaft once more 5 turns in each direction, so that the tapered roller bearing slips into place.

Formula:
"Stotal"	=	"S2*" + measured value + bearing pre-load

Example:
	Inserted shim(s) "S2*"	1.20 mm
+	measured value	0.62 mm
+	bearing pre-load (constant value)	0.30 mm
=	Total shim thickness "Stotal" for "S1" + "S2"	2.12 mm