A4 Sedan L4-1.8L Turbo (AEB) (1997)
72 mm ............................................................................................................................................................................................................. 180 mm
-
Set VW388 measuring lever to dimension "a:"
-
Determine play between teeth flanks as follows:
-
Turn ring gear until it contacts a tooth flank (end of backlash travel).
-
Set dial indicator to O with 2 mm preload.
-
Turn ring gear back until it contacts opposite tooth flank (backlash).
-
Read backlash and note.
-
Turn ring gear another 90° and repeat measurement 3 times.
Notes:
-
If pinion shaft turns when fuming differential, install 3177 clamp -A- so that an exact backlash measurement can be made.
-
Loosen clamping piece to turn the ring gear further.
-
Differential must be installed with cutout for differential bevel gears facing pinion shaft.
-
If 3177 clamp is installed, install differential 180° to final position and repeat measurements.
Determining average backlash
Add four measured values together and divide total by 4 to determine average.
Example:
1st Measurement
0.28 mm
+
2nd Measurement
0.30 mm
+
3rd Measurement
0.30 mm
+
4th Measurement
0.28 mm
__________
Total of measurements
1.16 mm
Result: The average backlash is 1.16 mm divided by 4 = 0.29 mm
Note:
-
If the measured values differ more than 0.06 mm from each other, the installation of ring gear or gear set itself may not be correct. Check
installation and replace gear set if necessary.
Determining thickness of shim S2
Formula:
S2 = S2* - backlash - lift
Example:
Installed shim S2*
1.20 mm