Drive pinion, adjusting

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Special tools and workshop equipment required

Fig 1: Universal Measuring Device VW 385

Courtesy of VOLKSWAGEN UNITED STATES, INC.

VW 385 Universal measuring tool

Fig 2: Holding Fixture VW 540

Courtesy of VOLKSWAGEN UNITED STATES, INC.

VW 540 Engine and transmission support

NOTE:

Before adjusting the drive pinion adjust the ring gear (ascertain total shim thickness "S" for shims "S1" + "S2"). Refer to Ring gear, adjusting .
Re-adjustment of the drive pinion is only necessary if the final drive set, taper roller bearing for drive pinion or housing for final drive is replaced. Adjustments. Refer to Adjustment overview .
Do not oil new taper roller bearings for frictional torque measurement. The bearings have already been treated with special oil by the manufacturer.

Determining shim "S3" thickness

(Setting preload of taper roller bearing for drive pinion)

Clamp final drive into assembly bracket. Refer to Rear final drive, attaching to assembly bracket .
Insert both outer races for the taper roller bearing without shims into the housing. Refer to Figure and Figure

Fig 3: Installing Small Taper Roller Bearing Inner Race

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Insert drive pinion without spacer sleeve.
Heat inner race for taper roller bearing to approx. 100°C and install onto drive pinion.

WARNING: WARNING!

Wear protective gloves!

NOTE:

Only install spacer sleeve for final frictional torque measurement (after determining shim "S3").
Install new taper roller bearings in delivery condition and do not oil.

Mount flanges for drive shaft and tighten hex nut for the flange. Refer to Figure

Fig 4: Identifying Special Tool

Courtesy of VOLKSWAGEN UNITED STATES, INC.

A - Torque gauge, commercially available, 0 to 600 Ncm

B - Socket, A/F 36

Tighten drive pinion nut until the following frictional torque is obtained.

New bearings	Used bearings 1)
200 to 250 Ncm	30 to 60 Ncm

1) With at least 50 km service

Fig 5: Setting Adjusting Rings Of Measuring Bar VW 385/1

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Set adjustment ring of universal mandrel VW 385/1.

Distance a = 60 mm

Set sliding adjustment ring.

Distance b = 55 mm

Fig 6: Assemble Measuring Bar According

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Assemble universal mandrel as illustrated.

Dial indicator extension VW 385/15 = 9 mm long

Set universal master gauge VW 385/30.

Ro = 57.50 mm

Set dial indicator (3 mm measuring range) to "0" with 2 mm preload.
Turn drive pinion 8 turns in both directions so that the taper roller bearings settle.

Fig 7: Placing Magnetic Plate Onto Drive Pinion Face

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Place end measuring plate VW 385/33 onto drive pinion head.

Fig 8: Insert Measuring Mandrel In The Housing

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Remove master gauge and insert measuring mandrel in the housing.

The centering disc for VW 385/3 faces toward cover for final drive

Install cover for final drive and tighten 4 bolts.
Using adjustable ring, move 2nd centering disc out as far as possible so that the mandrel can still just be turned by hand.

Determining measurement "e"

Fig 9: Insert Universal Mandrel And Perform Check Measurement

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Turn mandrel until the dial indicator point touches the end measuring plate on pinion shaft head, then measure maximum deflection (return point). The measured value is dimension "e" (in red range).

Measurement in following example: "e" = 1.60 mm

NOTE: Dimension "e" is required to determine thickness of shim "S3".

Then, (after removing universal mandrel) check again that the dial indicator, with master gauge VW 385/30 installed, indicates "0" with 2 mm preload, otherwise repeat the measurement.

Determining shim thickness "S3"

Formula:
"S3"	=	"e" - "r"
e	=	Determined value
r	=	Deviation (marked on ring gear in 1 /100 mm)

Example:
	Determined value "e"	1.60 mm
-	Deviation "r"	0.42 mm
=	Thickness of shim "S3"	1.18 mm

Determine shim(s) as accurately as possible from table. Part numbers

The following shims are available for "S3"

Shim thickness (mm) 1)
0.95	1.20	1.45
1.00	1.25	1.50
1.05	1.30	1.55
1.10	1.35
1.15	1.40

1) Using the shim tolerance variations it is possible to find the exact shim thickness required, insert two shims if necessary.

Remove universal mandrel.
Remove drive pinion and outer race for large taper roller bearing and reinstall with calibrated shims "S3" and spacer sleeves. Refer to Figure.
Insert inner race for small taper roller bearing and tighten drive pinion nut until specified frictional torque is achieved. Refer to Figure.

NOTE:

Do not oil new taper roller bearings for frictional torque measurement. The bearings have already been treated with special oil by the manufacturer.
Only increase tightening torque slowly and read-off frictional torque frequently. If the specified frictional torque is exceeded, the spacer sleeve must be replaced and the adjustment repeated. It is not possible to re-use a spacer sleeve that has been excessively compressed.

Set to following frictional torques:

New bearings	Used bearings 1)
200 to 250 Ncm	30 to 60 Ncm

1) With at least 50 km service

Performing check measurement

Checking dimension "r"

Turn drive pinion 8 turns in both directions so that the taper roller bearings settle.

Fig 10: Insert Measuring Mandrel In The Housing

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Insert universal mandrel and check measurement.

If the shims have been correctly selected, the dial indicator, reading counter clockwise (in red range), will show deviation "r" within a tolerance of ± 0.05 mm

Peen drive pinion nut with a punch.
The radial run-out at flange for drive shaft must always be measured and marked. Refer to Drive shaft flange, measuring and marking radial run-out .