Pinion Gear: Service and Repair

Pinion, Removing, Installing, Disassembling And Assembling














Special tools and equipment
^ VW295 Needle bearing drift
^ VW391 Puller
^ VW401 Thrust plate
^ VW402 Thrust plate
^ VW407 Punch
^ VW408 A Punch
^ VW412 Thrust disc
^ VW457 Support channels
^ VW460/2 Bolt
^ VW470/1 Assembly ring
^ 3146 Press support
^ VW540 Holding fixture
^ 30-205 Thrust pad
^ 3005 Thrust pad
^ 3028 Retainer
^ 3062 Thrust pad
^ 3138 Drift
^ 3143 Seal driver
^ 40-21 Sleeve
^ 2003 Seal installer
^ 3253 Wheel bearing assembly set
^ VAG1332 Torque wrench
^ VAG1383 A Engine/transmission lack


Note: Always replace both tapered roller bearings together as a set.

- Clamp rear final drive in holding fixture; see Fig. 1.





1. Nut
^ Removing; see Fig. 2
^ Tightening; see Fig. 14
^ Measuring friction torque; see Fig. 15
^ Securing; see Fig. 16
2. Drive flange
^ Pulling off; see Fig. 3
^ Installing; see Fig. 13
3. Seal
^ Replacing; Service and Repair
4. O-ring
^ Always replace
^ Lubricate with gear oil before installing; see Fig. 12
5. Small tapered roller bearing inner race (1)
^ Pressing out pinion; see Fig. 4
^ Installing; see Fig. 11
6. Small tapered roller bearing outer race (1)
^ Pulling out; see Fig. 5
^ Pressing in; see Fig. 10
7. Spacer sleeve (1)
^ Always replace
8. Final drive housings
9. Shim S3
^ Note thickness
^ Adjustment overview
10. Large tapered roller bearing outer racer (1)
^ Driving out; see Fig. 6
^ Fulling in; see Fig. 9
11. Large tapered roller bearing inner raced
^ Pressing off; see Fig. 7
^ Pressing on; see Fig. 8
12. Pinion (1)
^ Matched with ring gear, always replace together as a set.


(1) Adjustment work is required if these components are replaced; see Adjusting Marking. Adjustments






Fig. 1 Clamping rear final drive to holding fixture






Fig. 2 Removing nut for pinion
- Screw in two M8 x 30 bolts -A.-.
B - Deep socket insert, 36 mm
^ Rear final drive must be supported when loosening nut (e.g. with VAG1359/2 universal transmission mount in conjunction with VAG1383 A engine/transmission jack).






Fig. 3 Pulling off drive flange
Install two M8 x 30 bolts into flange -A-.






Fig. 4 Pressing pinion out of tapered roller bearing inner race






Fig. 5 Pulling out small tapered roller bearing outer race
A - (counter support, e.g. Kukko 22/2
B - Internal puller 46-56 mm, e.g. Kukko 21H






Fig. 6 Driving out large tapered roller bearing outer race
- After removing check shims for damage.






Fig. 7 Pressing off large tapered roller bearing inner race
A - Separating device 22-115 mm, e.g. Kukko 17/2






Fig. 8 Pressing on large tapered roller bearing inner race
- Heat inner race to approx. 100°C before pressing on.






Fig. 9 Pulling in large tapered roller bearing outer race
^ Inscription "oben" (top) on 3253/4 thrust washer faces nut on the puller.






Fig. 10 Pressing in small tapered roller bearing outer race
- Lubricate outer race first and press in using VW295 needle bearing drift and 30-205 thrust pad.






Fig. 11 Installing small tapered roller bearing inner race
- Install pinion with new spacer sleeve.
- Heat inner race to approx. 100°C.
- Press pinion up and press inner gracefully home up to stop using 40-21 sleeve.






Fig. 12 Installing O-ring
- Lubricate with gear oil before installing.






Fig. 13 Installing drive flange
- Drive drive flange onto pinion until nut can be installed.






Fig. 14 Tightening nut for pinion and adjusting friction torque
- Screw in two Me x 30 bolts -A-.
B - Deep socket insert, 36 mm
^ Rear final drive must be supported when tightening nut (e.g. with VAG1359/2 universal transmission mount in conjunction with VAG1383 A engine/transmission jack).

Note: Increase tightening torque slowly and check friction torque at regular intervals. If the prescribed friction torque is exceeded, the spacer sleeve must be replaced and the adjustment repeated. A spacer sleeve which has been compressed too much cannot be reused.






Fig. 15 Measuring friction torque
With commercially available torque gauge -A-, 0-600 Ncm (approx. 0-53 inch lbs.)
B -Deep socket insert, 36 mm
Set friction torque as follows






New bearings: 200 - 250 Ncm 18 - 22 inch lbs.)
Used bearings (1): 30 - 60 Ncm (3 - 5 inch lbs.)
(1) Run at least 50 km (30 miles)

Note: Use 3/4" to 1/2" reducer if necessary.






Fig. 16 Securing nut for pinion
- After securing nut, measure radial run-out at drive flange. Testing and Inspection