Audi Workshop Service and Repair Manuals

Adjusting pinion 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 t  Dial gauge extension, 30 mm Determining total shim thickness “Stotal” for shims “S3” plus “S4” (Setting preload of tapered roller bearings for pinion shaft) l  Differential removed

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

–  Press in tapered roller bearing outer race for pinion 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-.

–  Press tapered roller bearing inner race -1- onto pinion shaft and secure → Fig.. –  Fit selector gears and locking collar for 1st and 2nd gears -2- → Chapter. –  Press tapered roller bearing inner race -3- onto pinion shaft → Fig.. –  Insert completely assembled pinion shaft in 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. –  Maintain pressure and rotate pinion shaft 5 turns in both directions to seat tapered roller bearing.

–  Fit dial gauge (3 mm measuring range) with 30 mm dial gauge extension to gearbox housing. –  Preload dial gauge to 1 mm and set to “0”. The dial gauge extension must contact the machined surface on the face of the pinion.

–  Turn gearbox so that the gearbox cover points upwards. –  Rotate pinion shaft 5 turns in each direction so that the tapered roller bearing seats properly. Otherwise the result of the measurement will be incorrect. –  Read off play on dial gauge and note reading. t  Measurement in example: 0.46 mm   Note If the measuring procedure needs to be repeated, the pinion shaft must first be rotated 5 turns in each direction again so that the tapered roller bearing seats properly. 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)	0.12 mm
=	Total shim thickness “Stotal” for “S3” plus “S4”	1.59 mm

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

Example:
	Total shim thickness “Stotal” for “S3” plus “S4”	1.59 mm
–	Inserted shim “S4*”	1.01 mm
=	Thickness of shim “S3*”	0.58 mm

–  Remove tapered roller bearing outer race from gearbox housing → Fig.. –  Fit shim “S3*” in gearbox housing and install outer race again → Item. –  Insert completely assembled pinion shaft into gearbox housing again. –  Fit bearing housing and gearbox cover with the 4 dowel sleeves and tighten bolts to 35 Nm. –  Turn pinion shaft 5 turns in each direction so that tapered roller bearings seat properly.

–  Fit assembly device -VW 792- on gearbox housing; when doing so, insert an M12 nut -A- between assembly device -VW 792- and gearbox housing. –  Fit universal dial gauge bracket -VW 387- with dial gauge and 30 mm extension.   Note Apply dial gauge extension exactly at centre of intersection of ribs on gearbox cover -arrow-. –  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  0.06 ... 0.12 mm –  Tighten gearbox cover bolts again to 35 Nm. –  Take down measuring tools. –  Turn pinion shaft 5 turns in each direction so that tapered roller bearings seat properly. 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 settings: 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 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.

–  Remove master gauge and insert measuring tool into housing. 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 measuring tool can still just be turned by hand.

–  Turn measuring tool until tip of dial gauge touches end measuring plate on face of pinion gear and gauge indicates maximum deflection (return point). t  Measurement in following example: “e” = 0.17 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*”	0.58 mm
+	Allowance “r”	0.29 mm
–	Determined value “e” (in red scale)	0.17 mm
=	Thickness of shim “S3”	0.70 mm

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

Shim thickness (mm) 1)
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
1) 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”	1.59 mm
–	Thickness of shim “S3”	0.70 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) 1)
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
1) 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 with appropriate measured shims “S3” and “S4”. –  Turn pinion shaft 5 turns in each direction so that tapered roller bearings seat properly.

–  Insert universal measuring tool and perform check measurement. –  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.