Determining Correct Pinion Starting Shim
- If original ring and pinion is being installed, use original shim. If new parts (gear set) is being installed, use following steps to determine best starting shim thickness.
- Check numbers etched on drive pinion and ring gear. Measure thickness of original pinion shim. Note variance number on pinion gear. See Figure
. Note where old and new pinion marking columns intersect on chart. See Figure
.
- Intersecting figure represents amount needed to add or subtract from original shim. For example, if old pinion is +1 and new pinion is -3, intersecting figure is +.004" (+.10 mm). Add this amount to original shim. If old pinion is -3 and new pinion is -2, intersecting figure is -.001" (-.025 mm). See Figure
. Subtract this amount from original shim. See PINION VARIANCE CHART
below.
PINION VARIANCE CHART
| Old Pinion Marking / New Pinion Marking |
Starting Shim Needed |
| +4 |
| -4 |
+0.008 |
| -3 |
+0.007 |
| -2 |
+0.006 |
| -1 |
+0.005 |
| -0 |
+0.004 |
| +1 |
+0.003 |
| +2 |
+0.002 |
| +3 |
+0.001 |
| +4 |
0 |
| +3 |
| -4 |
+0.007 |
| -3 |
+0.006 |
| -2 |
+0.005 |
| -1 |
+0.004 |
| -0 |
+0.003 |
| +1 |
+0.002 |
| +2 |
+0.001 |
| +3 |
0 |
| +4 |
-0.001 |
| +2 |
| -4 |
+0.006 |
| -3 |
+0.005 |
| -2 |
+0.004 |
| -1 |
+0.003 |
| -0 |
+0.002 |
| +1 |
+0.001 |
| +2 |
0 |
| +3 |
-0.001 |
| +4 |
-0.002 |
| +1 |
| -4 |
+0.005 |
| -3 |
+0.004 |
| -2 |
+0.003 |
| -1 |
+0.002 |
| -0 |
+0.001 |
| +1 |
0 |
| +2 |
-0.001 |
| +3 |
-0.002 |
| +4 |
-0.003 |
| 0 |
| -4 |
+0.004 |
| -3 |
+0.003 |
| -2 |
+0.002 |
| -1 |
+0.001 |
| -0 |
0 |
| +1 |
-0.001 |
| +2 |
-0.002 |
| +3 |
-0.003 |
| +4 |
-0.004 |
| -1 |
| -4 |
+0.003 |
| -3 |
+0.002 |
| -2 |
+0.001 |
| -1 |
0 |
| -0 |
-0.001 |
| +1 |
-0.002 |
| +2 |
-0.003 |
| +3 |
-0.004 |
| +4 |
-0.005 |
| -2 |
| -4 |
+0.002 |
| -3 |
+0.001 |
| -2 |
0 |
| -1 |
-0.001 |
| -0 |
-0.002 |
| +1 |
-0.003 |
| +2 |
-0.004 |
| +3 |
-0.005 |
| +4 |
-0.006 |
| -3 |
| -4 |
+0.001 |
| -3 |
0 |
| -2 |
-0.001 |
| -1 |
-0.002 |
| -0 |
-0.003 |
| +1 |
-0.004 |
| +2 |
-0.005 |
| +3 |
-0.006 |
| +4 |
-0.007 |
| -4 |
| -4 |
0 |
| -3 |
-0.001 |
| -2 |
-0.002 |
| -1 |
-0.003 |
| -0 |
-0.004 |
| +1 |
-0.005 |
| +2 |
-0.006 |
| +3 |
-0.007 |
| +4 |
-0.008 |