Audi Workshop Service and Repair Manuals

Adjusting pinion shaft

(Adjusting pinion shaft with hollow shaft)

Repairs after which the pinion shaft must be adjusted → Chapter.

Special tools and workshop equipment required

t	Transmission removal lever -VW 296-

t	Support plate -VW 309-

t	Gearbox support -VW 353-

t	Universal measuring tool -VW 385-

t	Universal dial gauge bracket -VW 387-

t	Thrust plate -VW 402-

t	Press tool -VW 407-

t	Press tool -VW 412-

t	Assembly device -VW 792-

t	Thrust piece -2050-

t	Thrust pad -3062-

t	Sleeve -3144-

t  Wheel bearing tube -3345-

t  Dial gauge, e.g. -VAS 6080- t  Dial gauge extension, 30 mm t  Hose clip Determining total shim thickness „Stotal“ for shims „S3“ plus „S4“ (Adjustment of preload of tapered roller bearings for pinion shaft with hollow shaft) l  Differential removed

–  Press double tapered roller bearing inner race -1- onto pinion shaft and secure → Fig.. –  Fit large needle bearing -2-. –  Fit pinion shaft in hollow shaft -3-. l  Reassemble hollow shaft with selector gears and tapered roller bearing inner race. –  Fit small needle bearing -4-.

–  Press double tapered roller bearing outer race for pinion shaft into gearbox housing without shims.

–  Press in tapered roller bearing outer race for pinion shaft/hollow shaft with shim „S4*“ (thickness 1.01 mm) into bearing housing.   Note For measurement purposes a shim „S4“ with a thickness of 1.01 mm is inserted provisionally. This is referred to in the following as „S4*“. „S4*“ is exchanged with the final shim „S4“ after determining measured value „e“.

–  Secure gearbox housing onto gearbox support -VW 353- with bolts -arrows-. –  Fit fully assembled pinion shaft with hollow shaft into gearbox housing. –  Fit bearing housing and gearbox cover with the 4 dowel sleeves and tighten bolts to 35 Nm. –  Turn gearbox so that the gearbox cover points downwards.

–  Press down on face of pinion shaft with transmission removal lever -VW 296- until the tapered bearing outer race contacts the bearing housing. –  While still maintaining pressure, rotate the pinion shaft 5 turns in each direction in relation to the hollow shaft to settle the double tapered roller bearing. –  Then rotate the pinion shaft together with the hollow shaft 5 turns in each direction to settle the hollow shaft tapered roller bearing. –  Turn gearbox so that the gearbox cover points upwards. –  Turn pinion shaft with hollow shaft five turns in both directions so that the double tapered roller bearing settles. Otherwise the result of the measurement will be incorrect.

–  Set up measuring tool. –  Clamp pinion shaft onto hollow shaft with a hose clip -arrow-. –  Set dial gauge (3 mm measuring range) to „0“ with 1 mm preload.

–  Then move pinion shaft -A- with hollow shaft up and down in -direction of arrow-. –  Read off play on dial gauge and note reading. t  Measurement in example: 0.46 mm   Note If the measurement has to be repeated, pinion shaft with hollow shaft must first be rotated another 5 turns in each direction to settle the double tapered roller bearing. Preload dial gauge to 1 mm and set to „0“ again. Formula: „Stotal“ = „S4*“ + measured value + bearing preload

Example:
	Inserted shim „S4*“	1.01 mm
+	Measured value (example)	0.46 mm
+	Bearing preload (constant value)	0.15 mm
=	Total shim thickness „Stotal“ for „S3“ plus „S4“	1.62 mm

Determining thickness of shim „S3*“ Formula: „S3*“ = „Stotal“ – „S4*“

Example:
	Total shim thickness „Stotal“ for „S3“ plus „S4“	1.62 mm
-	Inserted shim „S4*“	1.01 mm
=	Thickness of shim „S3*“	0.61 mm

–  Remove double tapered roller bearing outer race, fit shim„S3*“ in gearbox housing and install outer race again → Item. –  Re-fit fully assembled pinion shaft with hollow shaft into gearbox housing. –  Fit bearing housing and gearbox cover with the 4 dowel sleeves and tighten bolts to 35 Nm. –  To settle the tapered roller bearings: rotate pinion shaft together with hollow shaft 5 turns in each direction, then rotate pinion shaft separately in relation to hollow shaft 5 turns in each direction.

–  Set up measuring tools using 30 mm dial gauge extension-A-; place M12 nut between -VW 792- and gearbox housing when securing bolt -arrow- to gearbox housing.   Note Apply 30 mm dial gauge extension-A- to rib in gearbox cover. –  Set dial gauge (3 mm measuring range) to „0“ with 1 mm preload. –  Loosen gearbox cover bolts and turn pinion shaft several times. –  If the correct shims have been selected the dial gauge will now indicate the following value: t  0.09 ... 0.18 mm –  Tighten gearbox cover bolts again to 35 Nm. –  Take down measuring tools. –  To settle the tapered roller bearings: rotate pinion shaft together with hollow shaft 5 turns in each direction, then rotate pinion shaft separately in relation to hollow shaft 5 turns in each direction. Determining dimension „e“   Note Measurement „e“ is required to determine the final shim thickness of „S3“ and „S4“.

–  Set adjustment rings of universal measuring tool -VW 385/1- to the following values: t  Dimension -a- = 45 mm t  Dimension -b- = 75 mm

–  Assemble universal measuring tool -VW 385/1- as illustrated: t  Dial gauge extension -VW 385/15-, 9.3 mm long t  Master gauge -VW 385/30- –  Set master gauge -VW 385/30- to Ro = 59.65 mm and fit onto universal measuring tool. –  Set dial gauge (3 mm measuring range) to „0“ with 2 mm preload.

–  Place end measuring plate -VW 385/33- on face of pinion gear.   Note Ensure contact surface of end measuring plate fits exactly and is free of oil.

–  Detach master gauge -VW 385/30- and insert universal measuring tool in housing. t  Dial gauge extension -VW 385/15--A- (length = 9.3 mm) must be screwed in. t  The dial gauge faces towards the final drive cover –  Fit cover for final drive and tighten 4 bolts to 20 Nm. –  Using the adjustable ring, pull 2nd centring disc -VW 385/36- out as far as possible so that the universal measuring tool can still just be turned by hand.

–  Turn universal measuring tool until tip of dial gauge touches end measuring plate on face of pinion gear, and measure maximum deflection (return point). t  Measurement in following example: „e“ = 0.26 mm (in red scale)   Note Then (after removing universal measuring tool), check once again that the dial gauge indicates „0“ with 2 mm preload when master gauge -VW 385/30- is in place. Determining thickness of shim „S3“ t  The allowance „r“ in relation to the master gauge „Ro“ is measured for the final drive gear sets supplied as replacement parts and marked on the outer circumference of the crown wheel. t  Subtract value „e“ if measurement is obtained on red scale. t  Add value „e“ if measurement is obtained on black scale. Formula: „S3“ = „S3*“ + „r“ + „e“ („e“ on black scale) „S3“ = „S3*“ + „r“ – „e“ („e“ on red scale)

Example:
	Inserted shim „S3*“	0.61 mm
+	Allowance „r“	0.38 mm
-	Determined value „e“ (in red scale)	0.26 mm
=	Thickness of shim „S3“	0.73 mm

–  Determine shim(s) according to table. For part number, refer to → Electronic parts catalogue. Available shims for „S3“

Shim thickness (mm)
0.53	0.85	1.17
0.57	0.89	1.21
0.61	0.93	1.25
0.65	0.97	1.29
0.69	1.01	1.33
0.73	1.05	1.37
0.77	1.09	1.41
0.81	1.13
The exact shim thickness required can be obtained by using the shim tolerance variations. Install two shims if necessary.

Determining thickness of shim „S4“ Formula: „S4“ = „Stotal“ – „S3“

Example:
	Total shim thickness „Stotal“ for „S3“ plus „S4“	1.62 mm
-	Thickness of shim „S3“	0.73 mm
=	Thickness of shim „S4“	0.89 mm

–  Determine shim(s) according to table. For part number, refer to → Electronic parts catalogue. Shims available for „S4“

Shim thickness (mm)
0.33	0.73	1.13
0.37	0.77	1.17
0.41	0.81	1.21
0.45	0.85	1.25
0.49	0.89	1.29
0.53	0.93	1.33
0.57	0.91	1.37
0.61	1.01	1.41
0.65	1.05	1.45
0.69	1.09	1.49
The exact shim thickness required can be obtained by using the shim tolerance variations. Install two shims if necessary.

Checking adjustment Checking allowance (tolerance) „r“ –  Install pinion shaft and hollow shaft with determined shims „S3“ and „S4“. –  Turn hollow shaft against pinion shaft five turns in both directions so that the double tapered roller bearing settles. –  Turn pinion shaft with hollow shaft five turns in both directions so that the tapered roller bearings settle.

–  Insert universal measuring tool and check adjustment. –  Read off dial gauge anti-clockwise (red scale). t  If the shims have been correctly selected, the allowance „r“ (marked on outer circumference of crown wheel) should be indicated within a tolerance of ± 0.04 mm.