Adjusting the distance between the end face of the final drive pinion and the axle of the differential

Adjustment principle

The distance between the axis of the differential and the end of the drive gear determines the location of the contact patch in the meshing of the final drive gears. When installing the output shaft in the gearbox, this distance affects the degree of wear and noise of the final drive gears. Therefore, it must be adjusted with great care using a special tool.

The initial value for adjustment is the calculated value of the distance between the axis of the differential and the end face of the drive gear (size «Ro», see diagram), corrected by the amendment «G», determined during the manufacture of the drive gear. The adjustment consists in placing the adjusting ring S3 of the required thickness under the outer ring of the rear output shaft bearing to displace the drive gear in the gearbox housing.




Determination of the correction value «G»

Note. This measurement is made if there is no correction marking on the driven gear of the final drive «G» in hundredths of a millimeter from the nominal position of the drive gear, and also if there has been a replacement of parts that directly affect the position of the drive gear of the final drive: the rear double-row tapered roller bearing of the output shaft, the crankcase or the rear cover of the gearbox, the bearing of the 1st gear gear.

Remove the gearbox rear cover.

Install a special adjusting washer VW 381/11 and fasten it strictly at a right angle relative to the output shaft by hand-tightening two M8x50 bolts.

Tighten bolts to 2 Nm using a torque wrench.

The drive gear, after tightening the bolts, takes the position in which it was when the rear cover of the gearbox was installed. This operation must be carried out very carefully whenever the distance between the end of the pinion gear and the axle of the differential is adjusted.

Remove differential.

Install measuring mandrel VW 385 (calibrated for preload 2 mm) on «zero» using the indicator VW 385-30.

Determine the estimated size «G», which is a deviation from the size «Ro».

When replacing parts by selecting the thickness of the adjusting ring, achieve the maximum possible accuracy of maintaining the resulting size «G».

Selection of the adjusting ring of the rear bearing of the secondary shaft

If the final drive is to be used again, press the rear bearing outer race together with the old adjusting ring into the gearbox housing. When replacing parts, install the bearing outer ring without the adjusting ring.


Install the output shaft and press on the second inner race of the rear bearing, as well as the 5th gear.

Attach the gearbox housing to the clutch housing with a new gasket.

Tighten the rear end nut of the output shaft to 10.0 kgf·m.

Fit the special output shaft preload adjusting shim VW 381/11 as described above.

Install measuring mandrel VW 385 (calibrated for preload 2 mm) on «zero» using the indicator VW 385-30, measure the value «G» and compare it with the calculated value «G», if the main gear was replaced, or with the value marked on the driven gear, when the main gear was replaced. If the resulting value «G» less than the calculated one, then a thicker adjusting ring S3 should be installed, and vice versa. The difference between the received and calculated values «G» indicates by how much to reduce or increase the thickness of the adjusting ring S3.

Remove the gauge set and install the matched adjusting ring S3 under the output shaft rear bearing outer race.

Install the output shaft.

Differential bearing preload and gear backlash adjustment

These operations are carried out as described for gearbox type 014, see section «Four speed gearbox».