Differential Case Assembly to Carrier

Pinion and Ring Gear Backlash

1. Assemble ring gear to case. Use new grade 9 bolts. Tighten bolts alternately and evenly to 95-122 Nm (70-90 lb-ft) for Model 44 and 129-142 Nm (95-105 lb-ft) for Model 50.

2. Place the case into position in the carrier. Master bearings should still be installed.

3. Force the case away from the drive pinion gear until it is completely seated against the cross bore face of the carrier. Position Dial Indicator/Magnetic Base D78P-4201-B or Dial Indicator with Bracketry TOOL-4201-C or equivalent so the indicator tip rests on a bolt of the case. Zero the dial indicator.

   
   
   
   
   

4. Force ring gear against drive pinion gear. Rock ring gear slightly to make sure gear teeth are in contact. Then, force ring gear away from drive pinion gear, making sure the dial indicator returns to zero. Repeat this procedure until the dial indicator reading is the same.

   This reading reveals the amount of shims necessary between the case and differential bearing (4221) on the ring gear side.

5. Remove the case from the housing. Remove the master bearings from the case.

6. As determined in Step 4, place the required amount of differential bearing shims (4067) on the ring gear hub of the case. For example, if the reading in Step 4 was 1.14mm (0.045 inch), place 1.14mm (0.045 inch) amount of differential bearing shims on the hub of the ring gear side of the differential case.

7. Install the differential bearing on the hub of the ring gear side of the case. Drive the differential bearing onto the hub using Differential Side Bearing Replacer T80T-4000-J.

   
   
   
   
   

8. To determine the correct amount of differential bearing shims to be placed on the hub of the drive pinion side of the differential case, subtract the reading obtained in Step 4 from the Total Differential Case End Play. Total case end play was determined in Steps 3 through 5 of Total Differential Case End Play. When this amount is determined, add 0.26mm (0.010 inch) to the amount. This is the required amount of differential bearing shims to be placed on the hub of the drive pinion side of the differential case.

   For example, total case end play was 2.30mm (0.091 inch). The reading in step 4 was 1.14mm (0.045 inch), and when subtracted from 2.30mm (0.091 inch) gives 1.16mm (0.046 inch), 0.26mm (0.010 inch) is added to give 1.42mm (0.056 inch) amount of differential bearing shims to be placed on the hub of the drive pinion side of the differential case.

9. Place the required amount of shims on the hub of the drive pinion side of the differential case.

10. Install the differential bearing on the hub of the drive pinion side of the case. Place Step Plate D80L-630-5 or equivalent on the ring gear side bearing to protect the differential bearing.

11. Drive the differential bearing onto the hub of the drive pinion side of the differential case using Differential Side Bearing Replacer T80T-4000-J. Place the Pinion Bearing Cone Replacer T53T-4621-B on the ring gear differential bearing to prevent damage.

12. Install the differential bearing cups (4222) on the differential bearings.

13.  CAUTION: When performing next step, do not exceed 0.25mm (0.01 inch).

    With the Differential Housing Spreader TOOL-4000-E, Differential Housing Spreader Adapter T80T-4000-B and Dial Indicator with Bracketry TOOL-4201-C or equivalent installed on the differential case, spread the carrier housing (not more than 0.25mm [0.01 inch]).

14. NOTE: Be careful to not nick the teeth of the ring gear or pinion.

    Install the differential case in the carrier. If necessary use a rawhide or plastic hammer to seat the case into the carrier housing cross bore. With partial and non-hunting/partial ring gear and pinion sets, align the marks on the ring gear and drive pinion if required.

15. Remove the spreader and dial indicator from the differential case.

16. Install bearing caps and bolts. Make sure the letters stamped on the caps correspond in both position and direction with the letters stamped into the carrier. Tighten bolts to 108-122 Nm (80-90 lb-ft).

17. Rotate the pinion and differential assembly several revolutions to seat differential bearings.

18. Install Dial Indicator with Bracketry TOOL-4201-C or equivalent on the case. Check ring gear and pinion backlash at three equally spaced points on the ring gear. Backlash tolerance is 0.13-0.23mm (0.005-0.009 inch) and cannot vary more than 0.08mm (0.003 inch) between the three points. For more information, refer to Gear Tooth Contact Pattern Check in the Disassembly and Assembly portion of this section for backlash tolerance.

    
    
    
    
    
    
    
    
    

19. Obtain a gear tooth contact pattern check. Refer to Gear Tooth Contact Pattern Check in the Disassembly and Assembly portion of this section prior to complete reassembly.

20. NOTE: Clean, oil free surfaces are required for proper curing and sealing.

    Apply a bead 3.175-6.35mm (1/8-1/4-inch) high and wide of Silicone Rubber Sealant D6AZ-19562-AA (clear) or -BA (black) or equivalent meeting Ford specifications ESB-M4G92-A and ESE-M4G195-A on the mating surfaces of the carrier mounting face support arm.

    Allow one hour curing time after the axle carrier is assembled to the axle arm before installing lubricant and operating vehicle.

    
    
    
    
    

21. Mount the differential to the left-hand axle arm using two guide pins, being careful not to smear gasket sealant. Install and tighten bolts to 41-54 Nm (30-40 lb-ft).

22. Use new bolts with encapsulated adhesive or wire brush the old bolts and apply thread-locking compound Threadlock® and Sealer EOAZ-19554-AA or equivalent meeting Ford specification WSK-M2G315-A5 (Type II).

23. Install support arm tab bolts to side of carrier and tighten to 115-135 Nm (85-100 lb-ft).