Ring Gear, Adjusting
Ring gear, adjusting, 01A, 5 SPD. M/T (AWD)
(Adjusting differential)
Special tools, testers and auxiliary items required:
^ Extension Pin 6 mm VW382/10
^ Magnetic Plate 50 mm Dia. VW385/17
^ Clamping piece VW 386 A
^ Dial gauge holder VW 387
^ Measuring lever VW 388
^ Thrust plate VW 402
Special tools, testers and auxiliary items required:
^ Punch VW 408 A
^ Extractor lever VW 681
^ Thrust plate 2050
^ Ring gear adjustment device VW 521
^ Torque wrench V.A.G. 1331
^ Dial gauge
A new ring gear adjustment is required when the following components have been replaced:
Transmission housing, final drive cover, tapered roller bearing for differential, differential housing or gear set
Determine total shim thickness "S total" for adjustment shims "S1" + "S2"
(adjust preload of tapered roller bearing for differential)
^ Drive pinion removed
^ If only the tapered roller bearing for differential has been replaced, ring gear can be removed from differential housing. Pinion shaft then does not need to be removed.
^ Remove flange shaft seals using extractor lever VW 681.
^ Remove tapered roller bearings for differential and remove adjustment shims.
^ Drive outer race for small tapered roller bearing together with shim "S2" into differential housing Use a shim "S2" with a 1.20 mm thickness for measurement purposes (2 shims with 0.60 mm).
Note: For the initial measurement, an adjustment shim "S2" with a thickness of 1.20 mm is inserted. It is designated as "S2" in the following. After determining backlash, "S2" is replaced by final "S2"
^ Pressing outer race for tapered roller bearing without shim "S1" into cover for differential or
^ Insert differential without sensor wheel for Speedometer Vehicle Speed Sensor (VSS) G22 into transmission housing. Ring gear is located on left side in front of final drive cover.
^ Install cover for differential and tighten four bolts to 25 Nm.
^ Position transmission so that cover for differential faces upward.
^ Turn differential 5 rotations in each direction to seat tapered roller bearing.
^ Place magnetic plate VW 385/17 on differential.
^ Assemble measuring tool, use 30 mm dial gauge extension.
^ Set gauge (3 mm measuring range) - A - to "0" with 2 mm preload.
Note:
^ Tip of dial indicator must be positioned on the center of the differential.
^ Lift the differential without turning it, read backlash on dial indicator and note.
Measured value in following example: 0.62 mm
Note:
^ To raise differential, secure special tools VW 52114 and VW 521112 at tight on differential (housing side).
^ If measurement is repeated, pinion shaft with hollow shaft must first be rotated 5 complete rotations in both directions again to settle tapered roller beating.
Formula: "S total" = "S2*" + measured value + bearing preload
Determining thickness of adjustment shim "S1*"
Note:
^ Initial shim "S1*" is replaced with final shim "S1" after backlash has been determined.
^ The total shim thickness "S total" if remains unchanged.
Formula: "S1" = "S total" - "S2"
Allocate adjustment shims via Electronic Parts Catalog (ETKA).
Measuring backlash
^ Drive pinion with shims "S3" and "S4" installed
^ Install differential with ring gear: S1 is on cover side, S2 installed in transmission housing.
^ Install cover for final drive and tighten bolts to 25 Nm. Insert locking sleeve VW 521/4 and VW 521/12.
^ Turn differential 5 rotations in each direction to seat tapered roller bearing.
^ Secure dial gauge holder VW 387 to housing.
^ Insert dial gauge with dial gauge extension VW 382/10 (6 mm).
^ Set measuring lever VW 388 to dimension "a" = 67 mm (for ring gear diameter 170 mm).
^ Determine backlash between teeth flanks as follows:
^ Turn ring gear until it contacts a tooth flank (end of backlash travel).
^ Set dial gauge to "0" with 2 mm preload.
^ Turn ring gear back until it contacts opposite tooth flank (backlash).
^ Read off backlash and note measured value.
^ Turn ring gear 90° every time and repeat measurement 3 times.
Note:
^ If pinion shaft turns when turning differential, install clamping piece VW 386 A so that an exact backlash measurement can be made.
^ Loosen clamping piece to turn the ring gear further.
Determining average backlash
^ Add the four measured values together and divide total by 4 to determine average.
^ Result: The average backlash is 1.16 mm / 4 0.29 mm
Note: If measurements vary more than 0.06 mm from each other, ring gear or gear set is not installed correctly. Check installation, replace gear set if necessary.
Determining thickness of adjustment shim "S2"
Formula: "S2" = "S2*" - backlash + lift
Determine shim(s) according to table. Part numbers Electronic Parts Catalog (ETKA)
Available shims for "S2"
Using shim tolerances it is possible to find the exact shim thickness required, insert two shims if necessary
Determining thickness of adjustment shim "S1"
Formula: "S1" = "S total" - "S2"
Determine shim(s) according to table. Part numbers Electronic Parts Catalog (ETKA)
Available shims for "S1"
Using shim tolerances it is possible to find the exact shim thickness required, insert two shims if necessary
Checking measurement
^ After installing adjustment shims "S1" and "S2", rotate differential 5 rotations in both directions so that tapered roller bearings settle.
^ Measure backlash 4 times on circumference.
^ Specified value: 0.12 to 0.22 mm
Note:
^ If backlash is outside tolerance, repeat adjustments. Do not change total shim thickness "S total" while doing so.
^ The individual measurement values can deviate a maximum of 0.06 mm from each other