Ring and Pinion Adjustments

1. Ring and Pinion Adjustments

2. Adjustments • There are four major adjustments/measurements to be made on a ring and pinion • Pinion depth • Pinion bearing preload • Backlash • Carrier bearing preload • If these four adjustments are correct the mesh pattern should be correct

3. Pattern • Having a correct pattern depends on correct backlash and pinion depth measurements • Correct pinion and carrier bearing preload ensures bearings will not fail prematurely

4. Pinion Depth • Usually adjusted with selective shims • Location of shims depends on style of differential housing • Gearsets are marked for pinion depth corrections • Example a GM pinion gear marked +3 • Measured pinion depth requires a .030 shim • Use a .027 shim • Insufficient pinion depth will move pattern towards crown • Excessive pinion depth will move pattern towards root

5. Pinion Markings

6. Pinion Depth

7. Pinion Bearing Preload • Preload is necessary to prevent the pinion from moving in and out of mesh with the ring gear under load • Two methods of setting • Crush sleeve • Shims • Preload is measured by checking pinion turning torque • Only the pinion installed • Pinion bearings lubricated with the proper lubricant • Use a beam type or a dial type inch pound torque wrench • If crush sleeve is overcrushed a new sleeve must be installed

8. Crush Sleeve VS Shims

9. Pinion Turning Torque

10. Backlash

11. Backlash • Backlash is the clearance between the pinion and ring gear • Necessary for lubrication and heat expansion • Adjusted by threaded adjusters or shims • Moving the ring gear toward the pinion will change backlash • Will also change pattern • Backlash is measured by pacing a dial indicator against a ring gear tooth and rocking the ring gear without moving the pinion • Must be set to specs • Do not use backlash to compensate for incorrect pinion depth • When setting backlash carrier bearing preload should also be set

12. Carrier Bearing Preload • Two types of adjustment • Shims • To set carrier bearing preload refer to OEM procedures and specifications • When setting backlash shims should be able to be inserted with a slight drag • To obtain preload insert equal size shims in both sides • Threaded adjusters • Usually 2-3 notches of preload • May be specified by case deflection

13. Threaded Adjusters

14. Housing Spreader • Used to remove carrier bearing preload for easier removal and installation of the carrier

15. Gear Pattern Check • Indicated proper positioning of drive pinion and ring gear • Before Checking ensure: • Carrier caps are properly torqued • Bearings are properly loaded • Backlash is correct • Method of checking • Coat 3 or 4 ring gear teeth with marking compound • Load the ring gear • Turn the ring gear in the drive direction • Turn the gear in the coast direction • Compare pattern to specs for the gearset you are checking

20. Gear Break-in • Properly breaking in new gears is very important • Drive 15-20 miles and let the differential cool • Keep the vehicle speed below 60MPH the first 100 miles • No towing or heavy use the first 500 miles • The first 45 miles of towing • Tow for 15 minutes let the gears cool for fifteen minutes • Change gear oil after the first 500 miles