Axle Disassembly

Service operations on the differential case (4204) assembly and the drive pinion assembly can be performed with the rear axle housing (4010) in the vehicle.

Sensor, Anti-Lock Brake

Removal

1. Raise vehicle on hoist. Refer to Section 00-02.

2. Carefully remove rear brake anti-lock sensor (2C190) .
   
   
   
   

Universal Joint Flange, Rear Axle and Flange Yoke Seal Removal

Removal

Replacement of flange yoke seal (4676) only involves removal and installation of the pinion nut and rear axle universal joint flange (4851) .

 CAUTION: This operation disturbs the pinion bearing preload, and this preload must be carefully reset when assembling.

1. Raise the vehicle and install safety stands. Refer to Section 00-02. Remove the rear wheels (1007) .

2. Make scribe marks on the driveshaft centering socket yoke (4782) and rear axle universal joint flange to ensure proper position of the driveshaft (4602) during assembly. Disconnect the driveshaft from the rear axle universal joint flange . Remove the driveshaft from the transmission extension housing. Install an oil seal replacer tool in the transmission extension housing to prevent oil leakage.
   
   
   
   

3. Install a Nm (lb-in) torque wrench on the pinion nut. Record the torque required to maintain rotation of the pinion through several revolutions.
   
   
   
   

4. While holding rear axle universal joint flange with Companion Flange Holding Tool T78P-4851-A, remove pinion nut.
   
   
   
   

5. Clean area around the flange yoke seal . Place a drain pan under flange yoke seal , or raise front of vehicle higher than rear.

6. Mark rear axle universal joint flange in relation to pinion shaft so rear axle universal joint flange can be installed in same position.
   
   
   
   

7. Remove rear axle universal joint flange using Companion Flange Remover T65L-4851-B.
   
   
   
   

    CAUTION: Do not damage rear axle housing while removing flange yoke seal .

8. Position screwdriver under flange of flange yoke seal and strike with hammer to wedge screwdriver blade between metal flange of flange yoke seal and rear axle housing .
   
   
   
   

9. Pry up on metal flange of flange yoke seal . Install gripping pliers and strike with hammer until flange yoke seal is removed.
   
   
   
   

Differential Case Removal

1. Raise vehicle and place jackstands under rear frame crossmember. Refer to Section 00-02. Lower the hoist so that the rear axle housing is at suitable working height.

2. Remove axle housing cover (4033) from the rear axle housing and drain lubricant.

3. Perform the inspection before disassembly. Refer to Cleaning and Inspection.

4. Remove rear wheels , rear disc brake calipers (2552) and rear disc brake rotors (2C026) . Refer to Section 06-04.

5. Working through cover opening, remove differential pinion shaft lock pin (4241) and remove the differential pinion shaft (4211) and differential pinion gears (4215) .
   
   
   
   

6. Remove rear brake anti-lock sensor as outlined.

7. Push axle shaft (4234) inward until rear axle shaft retaining u-washers (4N237) at button end of the axle shaft are clear of the side gear recess.

    CAUTION: Care should be taken not to damage inner wheel bearing oil seals (1177) when removing axle shafts from rear axle housing . In addition, axle shafts should be completely removed from rear axle housing .

8. Remove rear axle shaft retaining u-washers and pull axle shafts out of the rear axle housing .
   
   
   
   

9. Make scribe marks on the driveshaft , driveshaft centering socket yoke and rear axle universal joint flange to ensure proper alignment at assembly. Disconnect driveshaft from rear axle universal joint flange . Remove driveshaft assembly from vehicle. Insert an oil seal replacement tool in the transmission extension housing to prevent leakage.
   
   
   
   

    CAUTION: Bearing caps must be installed in their original positions.

10. Mark one differential bearing cap to help position the caps properly during assembly.
    
    
    
    

11. Loosen differential bearing cap bolts and bearing caps.

    Note direction of arrows on bearing caps. When assembled, the arrows must be pointing in the same direction as before removal.

12. Pry differential case , differential bearing cups (4222) and differential bearing shims (4067) out until they are loose in the bearing caps. Remove bearing caps and remove differential case from rear axle housing .
    
    
    
    

13. Inspect the differential bearings (4221) and differential bearing cups for damage. If they are damaged, remove the differential bearings using Differential Side Bearing Remover T70P-4221-A and Step Plate T81P-4220-A.
    
    
    
    

14. Install new differential bearings using Differential Side Bearing Replacer T57L-4221-A2.
    
    
    
    

Drive Pinion Removal

1. Mark rear axle universal joint flange in relation to the pinion shaft. Hold the rear axle universal joint flange with Companion Flange Holding Tool T78P-4851-A and remove the pinion nut. If a new differential ring gear and pinion (4209) is being installed, the rear axle universal joint flange need not be marked.
   
   
   
   

    CAUTION: Never use a hammer to remove the rear axle universal joint flange .

2. Remove rear axle universal joint flange with Companion Flange Remover T65L-4851-B.
   
   
   
   

3. With a soft-faced hammer, drive the pinion out of the differential pinion bearing (4621) and remove through the rear of the rear axle housing .

4. Remove flange yoke seal as outlined.

5. To remove and install the differential pinion bearing (4630) , use Pinion Bearing Cone Remover T71P-4621-B and Pinion Bearing Cone Replacer T53T-4621-C.
   
   
   
   

   NOTE: Measure the drive pinion bearing adjustment shim (4663) , which is found under the rear axle pinion bearing cup (4628) , with a micrometer and record the thickness (as a reference to be compared to the shim gauge reading prior to installing the rear axle pinion bearing cup ).

6. Remove the drive pinion bearing adjustment shim from the drive pinion.
   
   
   
   

   NOTE: The same differential pinion bearing used in this procedure must be used in final assembly of the axle.

Pinion Bearing Cup Removal

NOTE: To ensure proper seating, clean bores before installing new cups.

Inspect rear axle pinion bearing cups and if damaged remove from rear axle housing by tapping alternately (with a brass drift of suitable length) on each side of the rear axle pinion bearing cups to prevent rear axle pinion bearing cups from cocking in the rear axle housing bore.

Differential Case Runout Check

If the ring gear runout check (before disassembly) exceeds specification, the condition may be caused by a warped ring gear, a damaged differential case or loss of differential bearing preload. To determine the cause of excessive runout, proceed as follows:

1. With the pinion removed, place differential case/gear subassembly with differential bearings and differential bearing cups in rear axle housing .
   
   
   
   

2. Install a 6.75mm (0.265 inch) differential bearing shim on the LH side of subassembly.
   
   
   
   

3. Install the LH bearing cap finger-tight.
   
   
   
   

4. Install progressively larger differential bearing shims on the RH side until the largest differential bearing shim selected can be assembled with a slight drag feel.
   
   
   
   

5. Install the RH side bearing cap. Install bearing cap bolts. Tighten both RH and LH bolts to 95-115 Nm (70-85 lb-ft).
   
   
   
   

6. Rotate the assembly to ensure free rotation.
   
   
   
   

7. Install Dial Indicator with Bracketry TOOL-4201-C or equivalent. Check and note ring gear runout.
   
   
   
   

8. If the runout is within specification, the original out of specification runout was caused by insufficient differential bearing preload. If the runout exceeds specification, proceed to Step 9.

9. Remove differential case from the rear axle housing .
   
   
   
   

10. After removing rear axle differential gear case bolts (4216) , remove ring gear using a drift that will bottom in ring gear bolt holes. Strike at alternate holes around gear.
    
    
    
    

11. Install differential assembly in rear axle housing without ring gear.

12. Tighten bearing cap bolts to 95-115 Nm (70-85 lb-ft) and rotate assembly to ensure proper seating of differential bearings .

13. Check differential case runout again. If the runout is now within limits, the ring gear was out of specification and should be replaced. If the runout is still excessive, the differential case is damaged and should be replaced.