Differential Bearing Preload & Ring Gear Backlash
- With pinion depth set and pinion installed, place differential case and gear assembly, with bearings and cups, into axle housing. Install a .265" (6.7 mm) shim on left side (ring gear side) of differential.
- Install left bearing cap with bolts finger tight. Select largest shim that will fit with a slight drag and install on right side (pinion gear side) of differential. Install right bearing cap. Tighten all cap bolts to specification. See TORQUE SPECIFICATIONS table.
- Rotate ring gear to ensure free operation. Check ring gear backlash. See Fig 1 . Ring gear backlash should be within specification. See AXLE ASSEMBLY SPECIFICATIONS table. If ring gear backlash is within specification, go to step 7). If ring gear backlash is not within specification, go to step 5). If zero ring gear backlash was recorded, go to step 4).
- If zero ring gear backlash was recorded, add .020" (.51 mm) to shim size on right side and subtract .020" (.51 mm) from shim size on left side. Check ring gear backlash.
- If ring gear backlash is not within specification, increase shim thickness on one side and decrease shim thickness on opposite side by same amount. See Fig 2
. See BACKLASH-TO-SHIM THICKNESS CONVERSION
table for approximate shim change.BACKLASH-TO-SHIM THICKNESS CONVERSION
Required Change In Backlash In. (mm) Required Change In Shim Thickness In. (mm) .001 (.03) .002 (.05) .002 (.05) .002 (.05) .003 (.08) .004 (.10) .004 (.10) .006 (.15) .005 (.13) .006 (.15) .006 (.15) .008 (.20) .007 (.18) .010 (.25) .008 (.20) .010 (.25) .009 (.23) .012 (.30) .010 (.25) .014 (.36) .011 (.28) .014 (.36) .012 (.30) .016 (.41) .013 (.33) .018 (.46) .014 (.36) .018 (.46) .015 (.38) .020 (.51) - Install shim and bearing caps. Tighten bearing cap bolts to specification. See TORQUE SPECIFICATIONS table. Rotate ring gear several times. Recheck ring gear backlash. If ring gear backlash is within specification, go to step 7). If not, repeat step 5).
- Increase both left and right shim sizes .006" (.15 mm) and reinstall for correct bearing preload. Ensure shims are fully seated and ring gear assembly turns freely. Using marking compound, check gear tooth contact pattern. See GEAR TOOTH PATTERNS .