Rear differential problems

Very expensive,labor and parts probably over 1000 dollars.............probably better to look for a used one in a relatively low mileage wrecked vehicle. don-ohio (:^)

You must rebuild the entire rear end, all the bearings, you can't just installed the new bearing on the ring gear carrier. This bearing replacement job requires many specialized skills and many special tools to complete the adjustments required so the rear differential won't be noisy in operation.

The splines are on the inboard end of your axles. These need to match the "spider" gears as they are splined also.
Normally, a rebuild consists of all new bearings, but if you are replacing the spider gears also, just keep the same spline number of what's in it.
Note, replacing carrier bearing, watch closely for the shims, and keep them where they were. Also, mark your carrier bearing caps as to wher they were. And finally, if you do the pinion bearings, you need to set pre-load, and back lash!!!

There's not much inside there to see. Beginning at the driveshaf yoke, You have the nut that holds the pinion yoke on, a washer under that, a seal in the housing to keep the lube in, the outer pinion bearing another washer (or spacers, a crush collar and possibly a few more washers, the pinion bearing and the pinion gear itself. The carrier has a bearing on both ends held on to the housing by two end caps. Inside or on the housing you have the ring gear,four pinion gears and a shaft that holds the two free pinion gears in. That shaft has a 5/16 bolt in one end to keep it from sliding out of the carrier. The axles protrude through the two side gears and are retained by two "C" shaped retainers that can be removed only when the cross shaft has been removed. Sounds rather simple but, rebuilding them requires a lot of experience and dial indicators in order to get it right. Reading a gear contact pattern is part art, part science and getting it wrong will result in noise and quick failure. If you have a positraction unit, the posi plates and springs go inside the carrier and are a bit complicated to install without damaging them. There are many end to end differentials you can put under there available cheap from a scrapyard. Only requirement is to get the drum to drum length right and if it's a 4x4 the gear ration must match the one at the other end of the vehicle.On some, you may need to cut the spring mounts off and weld them in the proper places.
If you need info on a specific part inside the rear, ask.

You have to pull the cover off the rear end and let the fluid drain. Then there is a single small bolt that holds a pin in for the spider gears. You must remove the bolt, pin and spider gears. Then take the wheel and brake drum off the side you want to change. Once thats off you can push the axle in and a clip should fall off the axle inside the carrier. Then you can pull the axle out exposing the seal and bearing you need to change. Just use a seal pulling tool to pull the old seal out and the bearing is under that. It is pressed in so it can be hard to get out. Lots of times they have to be cut out. To put the new bearing back in just use a hammer and socket that is close to the size of the outter edge of the bearing. If you put the bearing in the freezer overnight it will go in a lot easier. Then tap a new seal in and put everything back together and refill the rear end with GL5 put the posi additive in if you have a posi trac rear end. Hope this helps good luck.

This is caused by a leaking rear axle seal you will need to pull the left rear axle out and change the seal and check for a worn axle bearing, this requires the removal of the differential cover, pin and center block or posi spring and clutch pack (if so equipped) and spider gears and then the "C" clip that retains the axle into the gear carrier, u will need a tube of silicone to reseal the cover and a axle seal installer tool and about 2 hours of your time

Block the front tires. Break the rear lugs loose. Jack up the rear of the truck at the center if possible. remove the wheels & brake drums. Remove the brake shoes,return springs & all the other hardware. Remove the differential cover & drain oil. If you have a posi the next step sucks. You need to remove the threaded pin from the housing & remove the axle retaining clips. All the while,being carefull of the spring in the posi unit. If no posi,then same procedure,minus the "pucker factor". After the axle is out,take a large flat blade screw driver or pry bar & pop the seal out. Keep in mind the axle bearing is probably gone too , so that's another procedure. Keep it apart,you'll be glad you did.

SECTION 205-02B: Rear Drive Axle/Differential — Ford 8.8-Inch Ring Gear 2003 Mustang Workshop Manual IN-VEHICLE REPAIR Axle Shaft Removal

1. Raise and support the vehicle. For additional information, refer to Section 100-02 .

1. Remove the wheel and tire assembly. For additional information, refer to Section 204-04 .

1. Remove the rear brake disc (2C026). For additional information, refer to Section 206-04 .

1. Remove the differential housing cover (4033) and drain the lubricant. For additional information, refer to Differential Housing Cover in this section.

1. Remove the differential pinion shaft (4211).
   1. Remove the differential pinion shaft lock bolt (4241).
   1. Remove the differential pinion shaft.

1. CAUTION: Do not damage the rubber O-ring in the axle shaft groove.
   Remove the U-washer (4N237).
   1. Push the axle shafts (4234) inboard.
   1. Remove the U-washer.

1. CAUTION: Damage to the rear brake anti-lock sensor (2C190) may occur if it is not removed before the axle shaft.
   Carefully remove the rear brake anti-lock sensor. For additional information, refer to Section 206-09A .

1. CAUTION: Do not damage the wheel bearing oil seal.
   Remove the axle shaft.

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Rear Wheel Bearing and Axle Shaft Oil Seal Removal

1. Remove the axle shaft (4234). For additional information, refer to Axle Shaft in this section.

1. NOTE: If the wheel bearing oil seal is leaking, the axle housing vent may be plugged.
   Using the special tools, remove the rear wheel bearing and wheel bearing oil seal.

Installation

1. Lubricate the new rear wheel bearing with the specified lubricant.

1. Using the special tools, install the new rear wheel bearing.

1. Lubricate the lip of the new wheel bearing oil seal.
   • Use Premium Long-Life Grease XG-1-C or equivalent meeting Ford specification ESA-M1C75-B.

1. Using the special tools, install the new wheel bearing oil seal.

1. Install the axle shaft. For additional information, refer to Axle Shaft in this section.

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Installation

1. Lubricate the lip of the wheel bearing oil seal
   • Use Premium Long-Life Grease XG-1-C or equivalent meeting Ford specification ESA-M1C75-B.

1. CAUTION: Do not damage the wheel bearing oil seal.
   Install the two axle shafts.

1. CAUTION: Do not damage the rubber O-ring in the axle shaft groove.
   Install the U-washer.
   1. Position the two U-washers on the button end of the axle shaft.
   1. Pull the axle shaft outward.

1. NOTE: If a new pinion shaft lock bolt is unavailable, coat the threads with Threadlock and Sealer EOAZ-19554-AA or equivalent meeting Ford specification WSK-M2G351-A5 prior to installation.
   Install the differential pinion shaft.
   1. Align the hole in the differential pinion shaft with the case lock bolt hole.
   1. Install a new differential pinion shaft lock bolt.

1. Install the differential housing cover and fill the rear axle with the specified lubrication. For additional information, refer to Differential Housing Cover in this section.

1. Install the rear brake anti-lock sensor. For additional information, refer to Section 206-09A .

1. Install the rear brakes. For additional information, refer to Section 206-04 .

1. Install the tire and wheel assembly. For additional information, refer to Section 204-04 .

1. Lower the vehicle.

Differential bearing caps 70-85 ft lb
Ring gear bolts 70-85 ft lb
Pinion bearing preload if using original bearings 8-14 lb-in, if installing new bearings 16-28 lb-in

REMOVAL

1. Remove filler plug from the differential cover.
2. Remove differential cover and drain the lubricant.
3. Clean housing cavity with flushing oil, light engine oil or a lint free cloth. NOTE: Do not use steam, kerosene or gasoline to clean the housing.
   
4. Remove axle shafts.
5. Remove RWAL/ABS sensor from housing. NOTE: Side play resulting from bearing races being loose on case hubs requires replacement of the differential case.
   
6. Mark differential housing and bearing caps for installation reference (REFERENCE MARKS).
7. Remove bearing threaded adjuster lock from each bearing cap.
8. Loosen differential bearing cap bolts.
9. Loosen differential bearing adjusters through the axle tubes with Wrench C-4164 (THREADED ADJUSTER TOOL).
10. Hold differential case while removing bearing caps and adjusters.
11. Remove differential case. NOTE: Tag the differential bearing cups and threaded adjusters to indicate their location.
    

INSTALLATION

1. Apply a coating of hypoid gear lubricant to the differential bearings, bearing cups, and threaded adjusters. A dab of grease can be used to keep the adjusters in position.
2. Install differential assembly into the housing.
3. Install differential bearing caps in their original locations (BEARING CAPS).
4. Install bearing cap bolts and tighten the upper bolts to 14 N·m (10 ft. lbs.). Tighten the lower bolts finger-tight until the bolt head is seated.
5. Perform the differential bearing preload and adjustment procedure. NOTE: Be sure that all bearing cap bolts are tightened to their final torque of 136 N·m (100 ft.lbs.) before proceeding.
   
6. Install axle shafts.
7. Apply a bead of orange Mopar Axle RTV Sealant or equivalent to the housing cover (COVER SEALANT). CAUTION: If cover is not installed within 3 to 5 minutes, the cover must be cleaned and new RTV applied or adhesion quality will be compromised.
   
8. Install the cover and any identification tag and tighten cover bolts to 41 N·m (30 ft. lbs.).
9. Fill differential with lubricant to bottom of the fill plug hole. Refer to the Lubricant Specifications for the correct quantity and type. NOTE: Trac-lok™ differential equipped vehicles should be road tested by making 10 to 12 slow figure-eight turns. This maneuver will pump the lubricant through the clutch discs to eliminate a possible chatter noise complaint.
   

DIFFERENTIAL BEARING PRELOAD AND GEAR BACKLASH The following must be considered when adjusting bearing preload and gear backlash:

• The maximum ring gear backlash variation is 0.076 mm (0.003 in.).
• Mark the gears so the same teeth are meshed during all backlash measurements.
• Maintain the torque while adjusting the bearing preload and ring gear backlash.
• Excessive adjuster torque will introduce a high bearing load and cause premature bearing failure. Insufficient adjuster torque can result in excessive differential case free-play and ring gear noise.
• Insufficient adjuster torque will not support the ring gear correctly and can cause excessive differential case free-play and ring gear noise.

NOTE: The differential bearing cups will not always immediately follow the threaded adjusters as they are moved during adjustment. To ensure accurate bearing cup responses to the adjustments:

• Maintain the gear teeth engaged (meshed) as marked.
• The bearings must be seated by rapidly rotating the pinion gear a half turn back and forth.
• Do this five to ten times each time the threaded adjusters are adjusted.

1. Through the axle tube use Wrench C-4164 to adjust each threaded adjuster inward until the differential bearing free-play is eliminated. Allow some ring gear backlash approximately 0.25 mm (0.01 in.) between the ring and pinion gear. Seat the bearing cups with the procedure described above.
2. Install dial indicator and position the plunger against the drive side of a ring gear tooth (RING GEAR BACKLASH). Measure the backlash at 4 positions, 90 degrees apart around the ring gear. Locate and mark the area of minimum backlash.
3. Rotate the ring gear to the position of the least backlash. Mark the gear so that all future backlash measurements will be taken with the same gear teeth meshed.
4. Loosen the right-side, tighten the left-side threaded adjuster. Obtain backlash of 0.076 to 0.102 mm (0.003-0.004 in.) with each adjuster tightened to 14 N·m (10 ft. lbs.). Seat the bearing cups with the procedure described above.
5. Tighten the differential bearing cap bolts 136 N·m (100 ft. lbs.).
6. Tighten the right-side threaded adjuster to 102 N·m (75 ft. lbs.). Seat the bearing cups with the procedure described above. Continue to tighten the right-side adjuster and seat bearing cups until the torque remains constant at 102 N·m (75 ft. lbs.)
7. Measure the ring gear backlash. The range of backlash is 0.15 to 0.203 mm (0.006 to 0.008 in.).
8. Continue increasing the torque at the right-side threaded adjuster until the specified backlash is obtained. NOTE: The left-side threaded adjuster torque should have approximately 102 N·m (75 ft. lbs.). If the torque is considerably less, the complete adjustment procedure must be repeated.
   
9. Tighten the left-side threaded adjuster until 102 N·m (75 ft. lbs.) torque is indicated. Seat the bearing rollers with the procedure described above. Do this until the torque remains constant.
10. Install the threaded adjuster locks and tighten the lock screws to 10 N·m (90 in. lbs.).