Audi Workshop Service and Repair Manuals

Re-determining shim “S4” when renewing bearing housing Special tools and workshop equipment required

t  Universal dial gauge bracket -VW 387-

t  Assembly device -VW 792-

t  Ruler -T40100-

t  Digital depth gauge, e.g. -VAS 6087- t  Dial gauge t  Dial gauge extension, 30 mm –  Clean housing flanges.

–  Place straightedge (e.g. -T40100-, 39.70 mm wide) -1- on housing flange. –  Measure difference between depth -a- on old and new bearing housing with a digital depth gauge (e.g. -VAS 6087-). Example:

	Depth -a- of previous bearing housing (with straightedge width)	46.50 mm
	Depth -a- of new bearing housing (with straightedge width)	46.65 mm
=	Difference	0.15 mm

–  If new bearing housing is deeper, install a thicker “S4” shim. –  If previous bearing housing is deeper, install a thinner “S4” shim. Example:

	Previous shim “S4”	0.95 mm
+	Difference	0.15 mm
=	New shim “S4”	1.10 mm

Shims available → . –  Press tapered roller bearing outer race with shim “S4” into bearing housing → Fig.. –  Insert completely assembled pinion shaft into gearbox housing again. –  Fit bearing housing and gearbox cover 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 If this reading is not obtained, the adjustment must be corrected.