Audi Workshop Service and Repair Manuals

Notes:

• ◆ Before adjusting the drive pinion adjust the crown wheel (ascertain total shim thickness "S" for shims "S1" + "S2") .
• ◆ 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 => Page 39-168.
• ◆ Do not additionally oil new taper roller bearings for frictional torque measurement. The bearings have already been treated with special oil by the manufacturer.

Ascertaining shim "S3" thickness

(Setting preload of taper roller bearing for drive pinion)

• ‒ Tensioning final drive in engine and gearbox bracket => Page 39-121.
• ‒ → Pull outer race for large taper roller bearing into housing without shim.

Note:

Inscription "Oben" ("top") with thrust pad 3253/4 faces the nut of the puller.

• ‒ → Pull outer race for small taper roller bearing into housing.
• ‒ Oil the outer race and mount it using press tool VW 408 A and thrust plate 30-205.

• ‒ → Insert drive pinion without spacer sleeve.

• ‒ Heat inner race for taper roller bearing to approx. 100 °C and fit onto drive pinion.

Notes:

• ◆ Do not additionally oil new taper roller bearings for frictional torque measurement. The bearings have already been treated with special oil by the manufacturer.
• ◆ Only install spacer sleeve for final frictional torque measurement (after determining shim "S3").

• ‒ → Fit support tool 3304 with two hexagon bolts M8 x 30.
• ‒ Final drive must be supported when tightening nut (e.g. using universal support V.A.G 1359/2 in combination with gearbox jack V.A.G 1383 A).
• ‒ Fit new drive pinion nut.
• ‒ Tighten drive pinion nut just far enough so that no play can be felt at drive pinion.
• ‒ Gradually increase tightening torque, checking friction torque at regular intervals, until specified friction torque is obtained.

•     A -    → Torque gauge, commercially available, 0 ... 600 Ncm
•     B -    Extension with 32 mm socket insert

• ‒ The following frictional torques should be set:

    1)    with at least 50 km service

• ‒ → Set adjustment ring of universal mandrel VW 385/1.
• ‒ Distance a = 60 mm
• ‒ Set sliding adjustment ring.
• ‒ Distance b = 55 mm

• ‒ → Assemble universal mandrel as illustrated.
• ‒ Dial gauge extension VW 385/15 = 9 mm long
• ‒ Set universal master gauge VW 385/30.
• ‒ Ro = 57.50 mm
• ‒ Set dial gauge (3 mm measuring range) to "0" with 2 mm preload.

Note:

Before performing following measurements turn drive pinion at least five turns in both directions, so that the taper roller bearings settle. Otherwise a false reading will be obtained.

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

• ‒ → Remove master gauge and insert measuring mandrel in the housing.
• ‒ The centring disc for VW 385/3 faces towards cover for final drive
• ‒ Fit cover for final drive and tighten 4 bolts.
• ‒ Using the adjustable ring, move 2nd centring disc out as far as possible so that the mandrel can still just be turned by hand.

Determining dimension "e"

• ‒ → Turn mandrel until the dial gauge 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).
• ‒ Dimension 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 gauge, with master gauge VW 385/30 fitted, indicates "0" with 2 mm preload, otherwise repeat the measurement.

Determining shim thickness "S3"

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

=> Parts List

The following shims are available for "S3"

    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 => fromPage 39-157.
• ‒ Insert inner race for small taper roller bearing and tighten drive pinion nut until specified frictional torque is achieved => Fig.39-162

Notes:

• ◆ Do not additionally 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:

    1)    with at least 50 km service

Performing check measurement

Checking dimension "r"

• ‒ Turn drive pinion at least 5 turns in both directions.
• ‒ → Insert universal mandrel and perform check measurement.
• ‒ If the shims have been correctly selected, the dial gauge, reading anti-clockwise (in red range), will show the deviation "r" within a tolerance of ± 0.04 mm

• ‒ → Peen drive pinion nut with a drift.